Planet Hunters Talk

C4 K2 finds

  • Martti_Holst_Kristiansen by Martti_Holst_Kristiansen

    The K2 C4 lightcurves are now online, thanks to Al Schmitt (HEK) for providing us with the long cadence PDCSAP_FLUX lightcurves for LcViewer.


    Apparent glitches (Midpt Time):

    2238.65 BKJD

    2271.76 BKJD

    2287.5 BKJD


    Planet Candidates (Transits):

    ID 210326405 (later check)

    ID 210331473 (later check)

    ID 210364628 (2262.14 BKJD) Unsure

    ID 210365511 (P = 3.952) possible cont.

    ID 210372242 (P = 32.824) Unsure

    ID 210388679 (2263.39 BKJD) Unsure

    ID 210389383 (P = 14.07) Maybe additional periodic signal

    ID 210395468 (2259.53 BKJD) Unsure

    ID 210400897 (later check)

    ID 210402237 (P = 10.996)

    ID 210448729 (later check)

    ID 210525500 (P = 1.369) probably cont.

    ID 210558622 (P = 19.564)

    ID 210568002 (P = 1.522) probably cont.

    ID 210577548 (P = 6.419)

    ID 210609658 (P = 14.113)

    ID 210626797 (probably cont.)


    Eclipsing Binary Candidates:

    ID 210316476

    ID 210321339

    ID 210327060

    ID 210329155

    ID 210341949

    ID 210348130

    ID 210350446

    ID 210354201

    ID 210355269

    ID 210355311

    ID 210356450

    ID 210360901

    ID 210361551

    ID 210361885

    ID 210362393

    ID 210367220

    ID 210367469

    ID 210370729

    ID 210372930

    ID 210373111

    ID 210375290

    ID 210376318

    ID 210376335

    ID 210378102

    ID 210379010

    ID 210385468

    ID 210385758

    ID 210386880

    ID 210386883

    ID 210387836

    ID 210388603

    ID 210391114

    ID 210397036

    ID 210401157

    ID 210403086

    ID 210404228

    ID 210408447

    ID 210411757

    ID 210412074

    ID 210413481

    ID 210414957

    ID 210421801

    ID 210426077

    ID 210426551

    ID 210427081

    ID 210433146

    ID 210434247

    ID 210437218

    ID 210437941

    ID 210438688

    ID 210447939

    ID 210451200

    ID 210453345

    ID 210454588

    ID 210454657

    ID 210464181

    ID 210464781

    ID 210467408

    ID 210470747

    ID 210471407

    ID 210471954

    ID 210472483

    ID 210474285

    ID 210475773

    ID 210476794

    ID 210484192

    ID 210489231

    ID 210492153

    ID 210493551

    ID 210495899

    ID 210501149

    ID 210512162

    ID 210513446

    ID 210522228

    ID 210530173

    ID 210538996

    ID 210555161

    ID 210562330

    ID 210568214

    ID 210572738

    ID 210574135

    ID 210574837

    ID 210576234

    ID 210577546

    ID 210581202

    ID 210586972

    ID 210589188

    ID 210589260

    ID 210591703

    ID 210593417

    ID 210598340

    ID 210604953

    ID 210609071

    ID 210619926

    ID 210622523


    HB:

    ID 210433394 (Looks nice!)


    DSCT/GDOR:

    ID 210318134

    ID 210344373

    ID 210344532

    ID 210348175

    ID 210354975

    ID 210364509

    ID 210373873

    ID 210374056

    ID 210375765

    ID 210376377

    ID 210384744

    ID 210390571

    ID 210395925

    ID 210408934

    ID 210413734

    ID 210421204

    ID 210424124

    ID 210427204

    ID 210429154

    ID 210437575

    ID 210438520

    ID 210441967

    ID 210449987

    ID 210460860

    ID 210462235

    ID 210468979

    ID 210471690

    ID 210491773

    ID 210498388

    ID 210516402

    ID 210517217

    ID 210529209

    ID 210530626

    ID 210544036

    ID 210568531

    ID 210586179

    ID 210596089

    ID 210608585


    CV/DN/LPV:

    ID 210332154


    RR-Lyrae Type:

    ID 210311535

    ID 210322126

    ID 210343581

    ID 210345648

    ID 210389601

    ID 210394470

    ID 210399040

    ID 210418729

    ID 210454384

    ID 210457607

    ID 210471429

    ID 210475866

    ID 210507908

    ID 210509604

    ID 210511418

    ID 210577318

    ID 210607917

    ID 210617106


    Asteroids encounters

    ID 210307221

    ID 210309341

    ID 210312511

    ID 210322477

    ID 210325299

    ID 210328701

    ID 210329073

    ID 210352551

    ID 210365226

    ID 210395925

    ID 210419493

    ID 210420672

    ID 210426073 (Numerous)

    ID 210428894 (Numerous)

    ID 210432795

    ID 210434976

    ID 210437334

    ID 210454684

    ID 210459199

    ID 210469180

    ID 210478124

    ID 210483775

    ID 210485181

    ID 210489346

    ID 210501536

    ID 210503612

    ID 210506844

    ID 210553950

    ID 210569604

    ID 210575024

    ID 210593490

    ID 210601109

    ID 210604966


    Others:

    ID 210352799

    ID 210398323

    ID 210480960

    ID 210494515 (check out later)

    ID 210553798

    ID 210600482

    ID 210614304

    Posted

  • Shellface by Shellface

    Cripes, that's quick. No time to stall in this business, eh.

    The campaign 4 field lies towards the centre of Taurus. If you know much about the constellation, then you'd know that two of the brightest and most important open clusters in the sky - the Hyades and Pleiades - lie over here, and you'd be right (see figure). As they are so important, many of the cluster stars have been studied fairly intensively for binaries, so I would recommend cross-checking with SIMBAD and other references. However, planetary transit searches in the area have been highly limited, so there's a lot of potential for new discoveries.

    Cluster members are well demarcated towards the edges of the field, and identifying those of interest should be a priority. Still, everything the photometry can tell about the cluster members is useful, because they're important benchmark stars in the <1 Gyr region (~900 and 120 Myr old, respectively). Planet hosts are only the foremost of these.

    Reddening in this field is somewhat varied - open space and the Hyades are somewhat modestly reddened, but the Pleiades are more strongly reddened because they are more distant and because the cluster is passing through a dust cloud.

    Anyway - if fortune is with us, this will be a very interesting field. If so, it could perhaps only be dethroned by campaign 5…

    Posted

  • zoo3hans by zoo3hans

    Planet Candidates (Transits):

    ID 210400751 Period about 16.02 days. Depth about 0.00025. At 2257.34, 2273.36, 2289.38.

    ID 210629082 Period about 27.3 days. Depth about 0.00045.

    ID 210731500 Period about 9.7275 days. At 2229.6, 2239.3, 2248.99, 2258.76, 2268.49, 2278.22, 2287.93, 2297.66.

    ID 210744272 Period about 22.8 days. At 2250.62, 2273.42, 2296.22. Depth 0.004.

    ID 210750726 Period about 4.6 days. Depth about 0.002.

    ID 210754505 Period about 0.87 days.

    ID 210769880 Period about 1.437 days. At 2229.6 etc.

    ID 210774732 Maybe single transit/eclipse at 2248.17.

    (Also bad cases (with a period around 11.41 days): ID 210774836 and ID 210774814 and ID 210771577 and 210750182 and 210735322 and 210731902.)

    ID 210777017 Period about 11.382 days. At 2237.34, 2248.70, etc. Depth about 0.001.

    (ID 210779624 Period about 5.705 days. This the same as below with other cases. Also we have alternating spacings. Probably another bad case of contamination. Sigh)

    ID 210780851 Period about 15.7825 days. It looks like a Warm Jupiter. Transit depth about 0.017. Nice U-shape.

    ID 210786627 Period about 1.72 days. For example at 2239.2, 2240.9, 2242.65, 2244.38, etc.

    (ID 21790246 Period about 11.405 days. Maybe BGEB like the others.)

    (ID 210814892 Period about 11.4 days. Maybe BGEB like the others.)

    ID 210819089 Maybe huge TTV's. Period about 17.3167 days.

    ID 210825751 Maybe single transit at 2275.95. Depth about 0.009.

    (ID 210829981 Period about 11.41 days. Hm, maybe BGEB like the others with this period.)

    ID 210836070 Maybe Multi.

    (ID 210837083 Maybe Multi. One period 11.4 days (starting at 2239.22). But could also be contamination by a BGEB of course.)

    (ID 210842555 Period about 5.703 days. Hey, this is practically the same as the candidate below, so maybe both are just contamination. Sigh.)

    (ID 210845609 Period about 5.705 days.)

    ID 210848071 Period maybe 41.72 days. At 2235.52 and 2277.24. Depth 0.0006.

    (ID 210854497 Period about 11.405 days. At 2239.21 etc.)

    (ID 210869095 Period about 11.41 (5.199 days or 6.30 apart), so maybe BGEB.)

    ID 210892669 Period about 5.649 days. Depth 0.0012. Rather V-shaped though.

    ID 210956385 Maybe transit at 2232.4 and a possible repeat at 2289.07. Period would be 56.655 days. Depth about 0.008.

    ID 210957318 Period about 4.0987 days. Depth 0.016. Nice Hot Jupiter.

    ID 210961508 Period about 0.3498 days. Starting at 2229.1.

    ID 210966398 Maybe single long transit at 2271.6 (although Martti mentioned a glitch very nearby).

    ID 210968143 Period about 13.74 days. At 2231.91, 2245.65, 2259.39, 2273.13, 2286.87. Depth 0.0017.

    ID 211002562 Period about 3.347 days. Nice Hot Jupiter. Depth 0.017.

    ID 211010922 Period about 40.7 days. At 2248.6, 2289.3. Depth 0.02.

    ID 211021753 Good dip at 2271.5.

    ID 211027550 Good dip at 2254.5. But could be a glitch. I see a similar dip with ID 210974434.

    ID 211041648 Maybe transits at 2248.2, 2275.2. Possible period around 27 days.

    ID 211051439 Maybe single transit at 2238.7.

    ID 211087003 Period about 28.3 days. At BKJD 2287.7, 2259.45, 2231.15 (depth 0.0015, duration 4.5 hours). Another larger transit at 2251 (depth 0.0079, duration 7 hours).

    ID 211089792 Period about 3.259 days. Maybe Hot Jupiter, depth about 0.025.

    ID 211099781 Period about 7.564 days. Nice Hot Jupiter.

    ID 211133138 Period about 7.435 days. For example at 2238.17, 2245.6, etc.

    ID 211147528 Period about 2.3485 days.

    ID 211169300 Period about 16.45 days. At 2234.8, 2251.25, 2267.7, 2284.15.

    Eclipsing Binary Candidates:

    ID 210626797

    ID 210634139

    ID 210642322

    ID 210650657

    ID 210654881 Nice eccentrical EB

    ID 210657179 Maybe contamination, depth is rather small.

    ID 210663545

    ID 210664740

    ID 210668314

    ID 210675130

    ID 210692406

    ID 210725198 Nice LC. Primary at 2258.18, secondary at 2234.74.

    ID 210734262

    ID 210734337

    ID 210740200

    ID 210742688

    ID 210744182

    ID 210744674 Period about 25.2 days. Depth 0.035.

    ID 210749423

    ID 210750052

    ID 210754756

    ID 210760314 Single eclipse at 2248.15.

    ID 210766835

    ID 210779706 Maybe period about 31.46 days.

    ID 210784039

    ID 210786891

    ID 210789323 Eclipse at 2240.72.

    ID 210793743

    ID 210801596

    ID 210805120

    ID 210821360

    ID 210822691

    ID 210823406 Single eclipse at 2257.35.

    ID 210832801 Very different sized stars.

    ID 210835735

    ID 210837460

    ID 210838192

    ID 210841030 Period about 10.36 days. The dips have alternating spacings, so probably BGEB.

    ID 210843343 Period about 11.405. Maybe contamination by BGEB.

    ID 210846734

    ID 210857749 Only one eclipse, but an obvious one.

    ID 210863062

    ID 210865148 Interesting pattern (i.e. tertiary system).

    ID 210876158

    ID 210879084

    ID 210903662 Period about 2.43 days, Depth only 0.0056. So maybe it could also be a Hot Jupiter.

    ID 210912231

    ID 210925707

    ID 210935498

    ID 210941737

    ID 210945342

    ID 210954859

    ID 210958990 Period about 1.7022 days. Depth 0.023. Probably an EB because I see small secondaries.

    ID 210960936

    ID 210961385

    ID 210965791

    ID 210969614

    ID 210974364 Period about 34.75 days.

    ID 210991175 Period about 6.8589 days. Small secondaries are visible between the V-shaped large dips.

    ID 210991175

    ID 211000135

    ID 211009047

    ID 211012889 (maybe contamination)

    ID 211013604

    ID 211014765

    ID 211015722

    ID 211017994

    ID 211019860

    ID 211020446

    ID 211036449

    ID 211041532

    ID 211064647 Eclipse at 2273.97. V-shaped. Could be a PC nevertheless. Depth 0.015.

    ID 211064990

    ID 211066849

    ID 211075893 Eclipse at 2253.76.

    ID 211075914 Eclipse at 2266.22, probably secondary eclipse at 2237.14 and 2279.93, possible period 42.79 days.

    ID 211082420 nice

    ID 211093684

    ID 211096084

    ID 211110438

    ID 211132787

    ID 211135350

    ID 211143504

    ID 211147178

    ID 211154046

    ID 211155479

    ID 211155977

    ID 211158357

    ID 211160700

    ID 211160717

    ID 211179336 short period EB or pulsating (shutter effect)

    ID 211179955

    ID 211182027 nice semi-detached EB

    DSCT/GDOR:

    ID 210672179 D

    ID 210747473 D

    ID 210752606 D

    ID 210762209 G

    ID 210794599 D

    ID 210814048 D

    ID 210845303 D

    ID 210850601 D

    ID 210857465 D

    ID 210999011 D

    ID 211016408 D

    ID 211020068 G

    ID 211022330 D

    ID 211023010 D

    ID 211028830 G

    ID 211044267 D

    ID 211046195 D

    ID 211046293 D

    ID 211053882 D

    ID 211079163 D

    ID 211083629 D

    ID 211083721 D

    ID 211086170 D

    ID 211089419 D (or regular periodic variable)

    ID 211093928 D

    ID 211104058 D

    ID 211109330 D

    ID 211115338 D

    ID 211118985 D

    ID 211150258 D

    ID 211161825 G

    ID 211173015 D

    ID 211178965 D

    ID 211193773 G

    RR-Lyrae Type:

    ID 210678680

    ID 210681941

    ID 210697426

    ID 210729707

    ID 210733035

    ID 210754711

    ID 210763406

    ID 210766289

    ID 210815465

    ID 210830646

    ID 210839363

    ID 210868876

    ID 210925792

    ID 210994946

    ID 211010071

    ID 211048310

    ID 211069540

    ID 211069629

    ID 220115899

    ID 220115902

    ID 220115904

    ID 220115915

    ID 220115916

    ID 220115917

    ID 220115935

    ID 220115936

    ID 220115942

    ID 220115946

    ID 220115949

    ID 220115951

    ID 220115952

    ID 220115954

    ID 220115955

    ID 220115959

    ID 220115960

    ID 220115962

    ID 220115969

    ID 220115970 (contamination?)

    ID 220115973

    Asteroids encounters:

    ID 210696380 at 2240.71 Erfjord

    ID 210747818 at 2250.58 Kythera

    ID 210748446 at 2246.76 Pandarus (Trojan)

    ID 210761838 at 2268.275 Kythera

    ID 210781898 at 2241.47 Wanda

    ID 210786719 at 2263.35 Wanda

    ID 210787202 at 2237.47 Wanda

    ID 210840966 at 2255.14 Onizaki

    ID 210905854 at 2235.48 Lindelof

    ID 210963351 at 2243.2 Brian

    ID 211107439 at 2297.47 Flare?

    ID 211110493 at 2261.96 1999 HN7

    ID 211194832 at 2264.4 Aglaja

    Others:

    ID 210662654 Maybe DN

    ID 211068547 funny LC (pulsating)

    ID 211081096 Maybe short period Cepheid. Period about 5.113 days.

    ID 211103863 Maybe short period Cepheid. Period about 6.154 days.

    ID 211106023 Maybe short period Cepheid. Period about 3.7233 days.

    ID 220115897 at 2264.1 maybe DN

    ID 220115908 at 2294.25 maybe DN

    ID 220115910 at 2291.8 maybe DN

    ID 220115958 at 2254.2 DN (Dwarf Novae)

    Maybe glitches:

    BKJD 2239.21

    BKJD 2250.61

    BKJD 2296.25

    (The EB and DSCT and Asteroid lists are not complete, I list only obvious cases)

    Posted

  • JKD by JKD

    ID 210626797 already mentioned, however it might be a 2 planet candidate

    1. at 2239.567 BKJD, p~ 43.377 d

    2. at 2265.066 BKJD

    Posted

  • ajamyajax by ajamyajax

    211002562: so our interesting planet hunting work continues with C4 data! As Hans Martin indicated with his findings, a nice hot Jupiter makes sense here. But with sparse data, a little more guesswork is also required for the transit duration and stellar estimates. A smaller star seems to work with the colors while a larger estimate fits better. But they are all still hot Jupiters in radii anyway. And TTV is possible also but not certain. Also noting this transit another one of those that seems related to the stellar cycle.

    s1=2229.11 p1=3.3475 d1=0.133 (3.20 hours +/-)

    ttv1= [2229.117,2232.447,2235.808,2239.1485,2242.498,2245.841,2249.192,2252.553,2255.88,2259.234,2262.584,2265.934,2269.286,2272.636,2275.987,2279.3295,2282.677,2286.019,2289.361,2292.7195,2296.061,2299.413]

    ttv1_gaps = [2235.808,2292.7195]

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    211002562 , 2MASS J03285136+2300557 , 11.241 , 10.891 , 10.795 , 0.35 , 0.096 , ('G8V', 0.94) , ('K1V', 0.86)

    au min-max 0.045 0.05

    stellar diameter in solar units min-max 1.19 1.36

    stellar mass in solar units min-max 1.085 1.49

    period in days min-max 3.345 3.351

    duration in hours min-max 3.151 3.244

    F1

    OC1

    T1

    Posted

  • ajamyajax by ajamyajax in response to JKD's comment.

    210626797: ok, three obvious transits to work with here. The first and third transits (a half transit actually) seem to be about the same shape and depth. And their fit is fairly stellar as shown here. The middle transit's depth is less than the others and is more planetary in shape which is good. So since all transits seem to be at planetary depth, two PC's are certainly possible. But there is also a chance of a blended eccentric binary here.

    s1=2239.568 p1=43.35 d1=0.25 (6.0 hours +/-)

    s2=2265.067 p2=? d2=0.21 (5.04 hours +/-)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210626797 , 2MASS J03371078+1720341 , 11.707 , 11.434 , 11.390 , 0.273 , 0.044 , ('G2V', 1.0) , ('A9V', 1.66)

    F1

    Posted

  • ajamyajax by ajamyajax

    211099781: another hot Jupiter candidate per Hans Martin. My program ranges vary with this data, so going with the smaller color estimate in the chart which uses a 0.96X R_sol star.

    s1=2231.475 p1=7.5643 d1=0.233 (5.6 hours +/-)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    211099781 , 2MASS J03441296+2433266 , 10.797 , 10.485 , 10.395 , 0.312 , 0.09 , ('G6V', 0.97) , ('G9V', 0.91)

    au min-max 0.07 0.09

    stellar diameter in solar units min-max 1.045 1.85

    stellar mass in solar units min-max 0.8 1.705

    period in days min-max 7.553 7.578

    duration in hours min-max 4.002 5.863

    F1

    Posted

  • ajamyajax by ajamyajax

    210389383: this find by Martti could also be a hot Jupiter, but since the transit depth is ~2.8x% the star would need to be on the small side here. I didn't see the additional signal mentioned but didn't look too closely for that yet.

    s1=2236.77 p1=14.087 d1=0.20 (4.8 hours or more)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210389383 , 2MASS J04102487+1313037 , 11.257 , 10.905 , 10.772 , 0.352 , 0.133 , ('G8V', 0.94) , ('K6V', 0.7)

    au min-max 0.11 0.14

    stellar diameter in solar units min-max 1.01 1.7

    stellar mass in solar units min-max 0.895 1.845

    period in days min-max 14.083 14.096

    duration in hours min-max 4.603 6.098

    F1

    Posted

  • troyw by troyw

    I think 210389383 has a secondary eclipse and is on an eccentric orbit.

    enter image description here

    Posted

  • troyw by troyw

    211002562 also has a secondary eclipse and has no eccentricity.

    Posted

  • ajamyajax by ajamyajax in response to troyw's comment.

    Agreed: 211002562 and 210389383 both show signs of blended secondary transits. 211002562 stronger than 210389383, but still very possible. So my HJ optimism for both was (edit: or could have been) premature. Thanks for helping with this and hope to see you contributing more often (when you have the time).

    Edit: there is still a chance the secondary is an albedo effect from a luminous HJ being eclipsed.

    Posted

  • JKD by JKD

    KID 210725198 - EB

    S1 at 2234.736, transit time ~16.18 hrs, Flux ~9100 ppm

    S2 at 2258.141, transit time ~18.63 hrs, Flux ~103277 ppm

    Posted

  • JKD by JKD

    KID 210744674 - pot. PC

    S at 2232.917 BKJD

    transit duration ~3.43 hrs

    Flux ~33769 ppm

    Posted

  • JKD by JKD

    KID 210685585 - pot PC

    S at ~2283.679 BKJD

    transit duration ~7.84 hrs

    Flux ~21468 ppm

    Posted

  • JKD by JKD

    KID 210709659 - interesting, very symmetric LC when eliminating some dots
    (a speculative Ring-Candidate)

    S at ~2294.988 BKJD

    transit duration ~23.537 hrs

    Posted

  • ajamyajax by ajamyajax

    210402237: has potential as a sub-Neptune using ~ 0.91X R_sol star for the radii estimate shown. The stellar estimates I get are also fairly consistent here.

    s1=2237.24 p1=11.0 d1=0.15 (3.6 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210402237 , 2MASS J03410141+1331098 , 10.358 , 9.998 , 9.907 , 0.36 , 0.091 , ('G8V', 0.94) , ('G9V', 0.91)

    au min-max 0.08 0.1

    stellar diameter in solar units min-max 0.73 0.945

    stellar mass in solar units min-max 0.565 1.105

    period in days min-max 10.988 11.013

    duration in hours min-max 3.559 3.696

    F1

    Posted

  • ajamyajax by ajamyajax

    210558622: another sub-Neptune candidate that seems to have consistent stellar parameters, and a star ~0.7X R_sol. Also maybe a ring or exomoon candidate with possible transit duration variations (TDV), although sparse or even blended data is another possible explanation.

    s1=2231.192 p1=19.584 d1=0.155 (3.72 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210558622 , 2MASS J04031027+1620509 , 10.231 , 9.649 , 9.496 , 0.582 , 0.153 , ('K5V', 0.75) , ('K6V', 0.7)

    au min-max 0.115 0.13

    stellar diameter in solar units min-max 0.595 0.705

    stellar mass in solar units min-max 0.53 0.765

    period in days min-max 19.566 19.575

    duration in hours min-max 3.603 3.79

    F1

    Posted

  • JKD by JKD

    210750182 - PC with 6 repeats, p=11.4d, starting at ~2239.2 BKJD

    Posted

  • JKD by JKD

    210760314 - an EB signature (already mentioned on page 1; some details below)

    S at ~2248.17 BKJD, td ~9.8 hrs, dFlux ~221289 ppm

    Posted

  • zoo3hans by zoo3hans in response to JKD's comment.

    Dear JKD

    regarding EPIC 210750182 : see my post on page 1, there are several cases with the same period - it must be some kind of contamination. I also noticed that it shows 2 dips spaced 5.x and 6.x days in between the 11.405 period or so in these cases. It seems that there is an eccentical EB somewhere in the field.

    Posted

  • JKD by JKD

    210766835 - interesting EB with p~24.78 d

    however transit duration and dFlux are varying significantly

    maybe there is a 3rd object around

    Posted

  • JKD by JKD in response to zoo3hans's comment.

    Hello zoo3hans,
    my search function was obviously not able to find your comment
    In the meantime I was successful

    BR
    Hans

    Posted

  • JKD by JKD in response to zoo3hans's comment.

    210775710 - PC

    p~59.876d

    starting at ~2291.556 BKJD

    transit duration ~6.37 hrs

    dFlux ~12074 ppm

    Posted

  • JKD by JKD

    210789323 - likely a PC with p~29.1 d at 2240.72 BKJD (see also page 1)

    Posted

  • ajamyajax by ajamyajax

    210577548: possible super-Earth MPC with a stellar radii ~= 0.73X R_sol. And there could be another PC here too, but all this needs to be checked later with more corrected data.

    s1=2232.00 p1=6.421 d1=0.105 (2.52 hours)

    s2=2235.59 p2=27.867 d2=0.17 (4.08 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210577548 , 2MASS J03431422+1638044 , 11.613 , 11.206 , 11.059 , 0.407 , 0.147 , ('K2V', 0.85) , ('K5V', 0.75)

    au min-max 0.055 0.065

    stellar diameter in solar units min-max 0.58 0.74

    stellar mass in solar units min-max 0.54 0.89

    period in days min-max 6.411 6.416

    duration in hours min-max 2.406 2.6

    au min-max 0.14 0.165

    stellar diameter in solar units min-max 0.565 0.73

    stellar mass in solar units min-max 0.47 0.77

    period in days min-max 27.898 27.908

    duration in hours min-max 4.002 4.399

    F1
    F2

    T1
    T2
    T3

    Posted

  • ajamyajax by ajamyajax in response to zoo3hans's comment.

    Re: 210744272: Hans Martin, is this another one of those bad cases you mentioned? Note changed period is similar to the others.

    s1=2239.21 p1=11.412 d1=0.14 (3.36 hours)

    (from an NEA proximity search)

    K2 Targets within search area

    EPIC Number RA [decimal degrees] Dec [decimal degrees] Distance [arc sec] Kepler-band [mag] Campaign Number

    210744272 54.7602 19.0220 0.09 13.152 4

    210744697 54.7494 19.0279 42.52 12.661 4

    210742585 54.7672 18.9956 97.89 16.187 4

    210743495 54.8003 19.0094 143.77 15.987 4

    210747750 54.7666 19.0740 188.54 11.851 4

    Posted

  • ajamyajax by ajamyajax in response to ajamyajax's comment.

    210836070: HM, this one could be contaminated by two P=11.41 transits (BGEB).

    Posted

  • ajamyajax by ajamyajax

    210568002: Martti from your list, possible blended BGEB here with half period transits visible at times through out this LC.

    s1=2230.01 p1=1.522 d1=0.07 (1.68 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210568002 , 2MASS J03581609+1629295 , 12.381 , 11.767 , 11.629 , 0.614 , 0.138 , ('K6V', 0.7) , ('K6V', 0.7)

    au min-max 0.02 0.025

    stellar diameter in solar units min-max 0.6 0.79

    stellar mass in solar units min-max 0.46 0.9

    period in days min-max 1.522 1.523

    duration in hours min-max 1.625 1.712

    F1
    T1

    Posted

  • JKD by JKD

    210823406 - mentioned as pot. EB on page 1 (some details below)

    S at 2257.35 BKJD

    transit duration ~6.37 hrs

    dFlux ~165879 ppm

    Posted

  • ajamyajax by ajamyajax

    210957318: yes could be a nice hot gas giant candidate, using ~0.87X R_sol for the star here. The transits could be blended at times so the durations I get vary some, but all possible stellar radii are still within PC ranges.

    s1=2230.802 p1=4.099 d1=0.10 (2.40 hours +/-)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210957318 , 2MASS J03292204+2217577 , 11.632 , 11.190 , 11.088 , 0.442 , 0.102 , ('K3V', 0.81) , ('K2V', 0.85)

    au min-max 0.04 0.05

    stellar diameter in solar units min-max 0.595 0.905

    stellar mass in solar units min-max 0.51 0.995

    period in days min-max 4.092 4.109

    duration in hours min-max 2.154 2.649

    F1
    F1a

    Posted

  • JKD by JKD

    210825751 - pot. PC (already mentioned on page 1)

    transit at ~2276.0 BKJD

    transit duration ~0.20 d

    dFlux ~8664 ppm

    Posted

  • JKD by JKD

    210832801 - EB (see page 1) with an additional smooth

    transit signature at 2299.45 BKJD

    transit duration ~5.88 hrs

    dFlux 1260 ppm

    Posted

  • JKD by JKD

    210857749 - already mentioned on page 1, details see below

    transit at ~2251.99 BKJD

    transit duration ~14.71 hrs

    dFlux ~179700 ppm

    Posted

  • ajamyajax by ajamyajax

    211089792: possible hot Jupiter candidate with a ~0.85X R_sol star. If the star is near Sun-size though, the estimated PC radius would be around 15.5X R_sol.

    s1=2231.427 p1=3.2594 d1=0.10 (2.4 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    211089792 , 2MASS J04104086+2424061 , 10.622 , 10.168 , 10.062 , 0.454 , 0.106 , ('K2V', 0.85) , ('K2V', 0.85)

    au min-max 0.035 0.045

    stellar diameter in solar units min-max 0.695 0.97

    stellar mass in solar units min-max 0.535 1.15

    period in days min-max 3.251 3.27

    duration in hours min-max 2.3 2.5

    F1
    F1a

    Posted

  • ajamyajax by ajamyajax

    210769880: speculative planet candidate around a 0.62X R_sol star, but also could be a BGEB.

    s1=2229.607 p1=1.43683 d1=0.065 (1.56 hours +/-)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210769880 , 2MASS J04100790+1924403 , 8.612 , 7.985 , 7.790 , 0.627 , 0.195 , ('K7V', 0.64) , ('K8V', 0.62)

    au min-max 0.02 0.02

    stellar diameter in solar units min-max 0.55 0.625

    stellar mass in solar units min-max 0.515 0.52

    period in days min-max 1.433 1.44

    duration in hours min-max 1.402 1.593

    F1
    F1a

    Posted

  • ajamyajax by ajamyajax

    210780851: although a fairly deep transit this is still a possible Jupiter PC, but note there is also a secondary transit (not pictured, see ephemeris).

    s1=2232.377 p1=15.7808 d1=0.25 (6.0 hours +/-)

    s2=2240.547 p2=15.7808 d2=0.25 (6.0 hours +/-)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210780851 , 2MASS J04031155+1934427 , 10.594 , 10.248 , 10.156 , 0.346 , 0.092 , ('G8V', 0.94) , ('K0V', 0.89)

    au min-max 0.125 0.15

    stellar diameter in solar units min-max 1.305 1.64

    stellar mass in solar units min-max 1.045 1.81

    period in days min-max 15.76 15.799

    duration in hours min-max 5.852 6.149

    Edit: a newer fit with more corrected data:

    F11

    Posted

  • ajamyajax by ajamyajax

    210819089: possible eclipsing binary.

    s1=2239.21 p1=34.22 d1=0.15 (3.6 hours)

    s2=2256.91 p2=34.22 d2=0.15 (3.6 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210819089 , 2MASS J03440216+2009354 , 11.517 , 11.009 , 10.885 , 0.508 , 0.124 , ('K3V', 0.81) , ('K3V', 0.81)

    T1

    Posted

  • ajamyajax by ajamyajax

    210609658: has one good transit in the MAST data, but at P=14.1x the duration might be too long to be planetary. Revisit with more corrected data.

    Update: only two good transits in the corrected data, but the long duration still looks stellar as does the wide range of these stellar estimates.

    s1=2241.395 p1=14.15 d1=0.51 (12.24 hours +/-)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210609658 , 2MASS J03425204+1706054 , 10.747 , 10.200 , 10.079 , 0.547 , 0.121 , K , ('K4V', 0.78) , ('K3V', 0.81)

    au min-max 0.155 0.19

    stellar diameter in solar units min-max 3.295 4.85

    stellar mass in solar units min-max 2.48 4.575

    period in days min-max 14.142 14.158

    duration in hours min-max 10.7 13.705

    F1

    Posted

  • zoo3hans by zoo3hans in response to ajamyajax's comment.

    EPIC 210389383 looks like a Hot Jupiter I think. Weak secondary transits are not unusual for big, hot Jupiters.

    Full LC:
    EPIC 210389383

    Zoom into LC:
    Zoom

    Impact Parameter Calculator of Kian ( http://www.kianjin.com/bcalc.html ):

    PC

    Posted

  • ajamyajax by ajamyajax in response to zoo3hans's comment.

    Dear Hans Martin, I certainly hope you are right. You and Martti (but mostly you) found a good number of these too, so looking forward to seeing what happens with them. Nice work. Sincerely, Mark

    Posted

  • ajamyajax by ajamyajax

    211147528: if we can look past the "picket fence" fit here, could be another possible hot gas giant planet candidate if a Sun size star (+/-).

    s1=2230.057 p1=2.3496 d1=0.10 (2.4 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    211147528 , 2MASS J03583532+2523189 , 10.884 , 10.710 , 10.619 , 0.174 , 0.091 , ('F6V', 1.25) , ('K0V', 0.89)

    au min-max 0.03 0.035

    stellar diameter in solar units min-max 0.645 1.045

    stellar mass in solar units min-max 0.65 1.04

    period in days min-max 2.345 2.357

    duration in hours min-max 1.801 2.498

    F1
    F1a

    Posted

  • ajamyajax by ajamyajax

    210744674: fairly deep transits at well over 2% and only one complete transit in the MAST data. Also the duration seems short for my stellar estimates here. So this one could be stellar, but check later with more corrected data (and to make sure not a glitch also). And sparse data so not pictured.

    s1=2232.92 p1=25.22 d1=0.14 (3.36 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210744674 , 2MASS J04232616+1901390 , 11.093 , 10.686 , 10.548 , 0.407 , 0.138 , ('K2V', 0.85) , ('K6V', 0.7)

    au min-max 0.17 0.17

    stellar diameter in solar units min-max 0.825 0.925

    stellar mass in solar units min-max 1.03 1.03

    period in days min-max 25.226 25.226

    duration in hours min-max 4.357 4.885

    Posted

  • ajamyajax by ajamyajax

    210775710: only two longer period partial transits here, but a possible planet candidate based on those partial shapes and transit depths, if not glitches. Check back with more corrected data.

    s1=2231.672 p1=59.865 d1=0.26 (6.24 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210775710 , 2MASS J03370580+1929585 , 10.631 , 10.307 , 10.208 , 0.324 , 0.099 , ('G5V', 0.98) , ('K3V', 0.81)

    au min-max 0.24 0.315

    stellar diameter in solar units min-max 0.68 0.945

    stellar mass in solar units min-max 0.515 1.165

    period in days min-max 59.826 59.867

    duration in hours min-max 6.002 6.392

    Posted

  • zoo3hans by zoo3hans in response to ajamyajax's comment.

    Another nice candidate from Martti, EPIC 210558622 :

    Full LC:
    EPIC 210558622

    Zooms into LC:
    Zoom1

    Zoom2

    Assuming a K7 star (J-H=0.735, H-K=0.149, J=10.231, H=9.645, K=9.469, Kepler_mag=12.034, delta_mag=0.0015, period=19.564 days, estimated Teff=4500K) :

    (using Kian's Planetary Kalculator)

    PC

    Posted

  • ajamyajax by ajamyajax

    210968143: a bit stellar or high impact or even blended, but a sub-Neptune planet candidate still seems possible here around small M-dwarf star (~0.55x R_sol).

    s1=2231.905 p1=13.745 d1=0.12 (2.88 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210968143 , 2MASS J03563656+2228216 , 11.168 , 10.495 , 10.360 , 0.673 , 0.135 , ('M7V', 0.098) , ('K6V', 0.7)

    au min-max 0.09 0.095

    stellar diameter in solar units min-max 0.52 0.61

    stellar mass in solar units min-max 0.515 0.605

    period in days min-max 13.742 13.75

    duration in hours min-max 2.808 3.142

    F1

    Posted

  • JKD by JKD

    210945342 - agree with zoo3hans, this one looks like an EB.
    However, there is an other interesting signal always ~0.14d before the signal starting at 2230.159 BKJD with about the same period like the EB (p~7.171d)

    Posted

  • zoo3hans by zoo3hans in response to JKD's comment.

    Dear JKD

    yes, the eclipse profile looks indeed very special. I assume it could be a large star spot, the eclipse duration is probably the whole feature, about 8.5 hours or so, since the secondary transit has also a rather long duration of about 8.5 hours (17 pixels). Maybe the orbits are locked and we see always the same side of the star during eclipse.

    Zoom into eclipse:
    eclipse

    Posted

  • Shellface by Shellface in response to zoo3hans's comment.

    I would agree that the anomalous profile of the transits is due to spots, as the out-of-transit variability is clearly enormous and roughly equal in period to the orbital one, which is compatible with some form of tidally locked binary (though the modest transit depth suggests the companion may be fairly small). As the two periods are the same, a spot would "follow" the companion along its orbit and would be crossed every transit it is present, so the anomaly should be repetitive. Spots vary in form on a scale of a few rotational periods, so the shape of the anomaly should likely vary with time to some extent.

    I would say that this is one of those peculiar objects for further study, because the scale of the phenomena it presents are extremely unusually large.

    Posted

  • JKD by JKD

    Potential DN Candidates

    ID 211079830 at 2274.608 BKJD

    ID 211098921 at 2259.652 BKJD

    Posted

  • JKD by JKD

    ID 211154046 - already mentioned on page 1 as EB

    maybe there is a planetary compagnion

    at 2247.332 BKJD with a

    duration time of 2.94 hrs and a

    minimal Flux of about 470 ppm

    Posted

  • ajamyajax by ajamyajax

    210525500: a tough one to fit, but perhaps a blended super-Earth planet candidate assuming a star ~0.9X R_sol. And at max depth, a PC here would still be only ~=2.4Re. Of course this transit could be contamination instead as Martti suggested earlier. Edit: there could be a secondary, but that would be blended also.

    s1=2230.258 p1=1.369 d1=0.075 (1.8 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210525500 , 2MASS J03354884+1549523 , 11.170 , 10.795 , 10.703 , 0.375 , 0.092 , ('G9V', 0.91) , ('K0V', 0.89)

    au min-max 0.02 0.025

    stellar diameter in solar units min-max 0.7 0.98

    stellar mass in solar units min-max 0.565 1.125

    period in days min-max 1.361 1.377

    duration in hours min-max 1.705 1.899

    F1
    F1a

    Posted

  • Martti_Holst_Kristiansen by Martti_Holst_Kristiansen

    Here are my corrected C4 results. Thanks to Al Schmitt (HEK) and Andrew Vanderburg (Harvard-Smithsonian Center for Astrophysics).

    Note: Several targets may overlap candidates listed by myself or Hans Martin on page 1.


    Apparent glitches:

    2242.67 BKJD


    ID (EPIC) | Period/Location


    Planet Candidates:

    210358034

    210363145 (P = 8.199) TTVs present

    210389383 (Possibly EB)

    210402237 (P = 10.998)

    210403955 Multi (at least 2 candidates)

    210423938 (Possibly cont.)

    210448987 (P = 6.102) Maybe cont.

    210474116 (2253.11 BKJD) Maybe glitch

    210500451 (2232.94 BKJD) Maybe glitch

    210508766 Perhaps Multi system, though cont. might cause the events.

    210509688 Could be glitches though

    210534924 (2264.57 BKJD) Possibly glitch

    EPIC 210558622 (P = 19.574)

    210559259 Maybe

    210566397

    210577548 - Multi system (P1 = 6.421) (P2 = 27.838)

    210578852 (2277.039 BKJD) Maybe

    210598340 (P = 3.732)

    210609658 (P = 14.136)

    210629082 (P = 27.328)

    210707130 (P = 0.6742)

    210718708 (P = 8.774)

    210731500 (P = 9.729)

    210750726 Probably cont.

    210754505 Probably cont.

    210764361 (2277.07 BKJD)

    210775710 (P = 59.835)

    210780851 Probably EB cont.

    210786627 Probably cont.

    210793739 Probably cont.

    210848071 (P = 41.691)

    210853606 (2248.72 BKJD)

    210903662 Probably cont.

    210956385 (P = 56.627)

    210957318 (P = 4.098)

    210958990 (P = 1.702)

    210961508 Probably cont.

    210965800 (P = 8.746)

    210968143 (P = 13.727)


    EB Candidates:

    210327060 Probably cont.

    210341949

    210343581

    210350446 Maybe PC present

    210355311

    210356450

    210361885

    210362393

    210367469

    210370729

    210373111

    210373873

    210375290

    210375765

    210376318

    210378102

    210386880

    210389383 (maybe planet)

    210391114

    210401157

    210403086

    210404228

    210411757

    210413481

    210414957 (Probably cont.)

    210426551

    210433146

    210434247 (Probably cont.)

    210437941

    210451200

    210453345

    210454588

    210467408

    210470747

    210471407

    210471954

    210472483

    210474285

    210475773

    210476794

    210483889

    210484192

    210489231

    210493551

    210501149 Maybe additional transit

    210512162

    210513446

    210522228

    210530173

    210555161

    210562330

    210568214

    210574135

    210576234

    210577546

    210581202

    210593417

    210609071

    210622523

    210626797

    210631263

    210634139

    210642322

    210650657

    210654881

    210663545

    210664740

    210668314

    210673168

    210675130

    210692406

    210701530

    210716489

    210720575

    210720772

    210725198

    210734262

    210734337

    210734643

    210739713

    210740200

    210740526

    210742688

    210744182

    210744674

    210749423

    210750052

    210754643

    210754756

    210757799

    210760314

    210766835

    210771656

    210779706

    210784039

    210784223

    210786847

    210786891

    210789323 Possibly additional transit at 2234.04 BKJD)

    210793743

    210796097

    210803087

    210805120

    210810957

    210817078

    210821360

    210822691

    210823406

    210824046

    210827030

    210832801

    210835735

    210837460

    210840112

    210843533 single dip

    210846736

    210857749

    210863062

    210865148 Triple EB

    210876158

    210879084

    210908413

    210912231

    210925707

    210935498

    210941737

    210945342

    210954667

    210954859

    210960936

    210961385

    210965791

    210969614

    210989020

    210989043

    210991175

    210991500


    HB:

    210433394

    210801596


    GDOR Candidates:

    210348175

    210354975

    210390571

    210396766

    210427204

    210437575

    210438520

    210460860

    210462235

    210491773

    210498388

    210516060

    210516402

    210517217

    210529209

    210568531

    210672179

    210692381

    210697335

    210711034

    210716115

    210725198

    210737134

    210746706

    210752606

    210758168

    210759464

    210769298

    210769793

    210772819

    210796886

    210806505

    210810961

    210819829

    210849044

    210859099

    210862604

    210895951

    210912256

    210948492

    210967051

    210977750


    DSCT Candidates:

    210344373

    210747473

    210765827

    210857465

    210979283


    Cepheid candidates:

    210855900


    RR Lyrae Candidates:

    210311535

    210322126

    210345648

    210389601

    210399040

    210418729

    210438688

    210454384

    210457607

    210464181

    210464781

    210475866

    210507908

    210509604

    210511418

    210511770

    210577318

    210600482

    210619926

    210665016

    210678680

    210697426

    210707203

    210729707

    210733035

    210754711

    210755194

    210763406

    210766289

    210815465

    210830646

    210831816

    210839363

    210868876

    210925792

    210933539


    CV/DN Candidates:

    210662654

    210670966

    210865655

    210886049

    210890552

    210911018


    Mira Variables:

    210332154

    210401066

    210418381

    210420328

    210421204

    210421801

    210439910

    210447586

    210472525

    210479001

    210479267

    210496777

    210520790

    210532727

    210666742

    210675756

    210686705

    210788181


    Other:

    210359769

    210427333

    210447206

    210488853

    210818897


    Asteroid Candidates:

    210312511

    210317331

    210322477

    210331148

    210331848

    210336461

    210338942

    210339090

    210341601

    210341825

    210342315

    210344843

    210349237

    210349838

    210352052

    210355269

    210355626

    210358866

    210360999

    210361325

    210362756

    210365226

    210365286

    210366107

    210366175

    210367033

    210368793

    210371702

    210371851

    210371890

    210372865

    210374294

    210375568

    210376151

    210376318

    210376917

    210379141

    210379999

    210382177

    210382657

    210387639

    210389478

    210391196

    210391582

    210391779

    210395925

    210397353

    210398038

    210401037

    210403086

    210403748

    210404228

    210404888

    210405044

    210407071

    210407396

    210412108

    210412589

    210417498

    210419253

    210419493

    210420164

    210420306

    210420401

    210422158

    210425323

    210425716

    210426073

    210426606

    210426688

    210427629

    210427758

    210428037

    210428344

    210428551

    210428765

    210430458

    210432080

    210432517

    210434525

    210434938

    210434976

    210435394

    210437356

    210440088

    210440093

    210442792

    210444246

    210446822

    210447014

    210448213

    210448947

    210450012

    210450449

    210451321

    210452146

    210452501

    210453085

    210453830

    210454404

    210454684

    210455646

    210455921

    210457290

    210458488

    210458576

    210458873

    210459047

    210459098

    210459199

    210460262

    210460381

    210462150

    210465351

    210465375

    210465397

    210466150

    210467231

    210467408

    210468157

    210469324

    210469721

    210470484

    210470525

    210470747

    210474992

    210475773

    210476385

    210476426

    210476837

    210477101

    210478124

    210478228

    210480098

    210480719

    210482495

    210483775

    210484276

    210485181

    210488694

    210489127

    210489239

    210489346

    210489853

    210490365

    210491103

    210491271

    210491311

    210493265

    210494413

    210494644

    210495014

    210495260

    210497173

    210497875

    210503288

    210503575

    210503612

    210505000

    210506107

    210507407

    210507827

    210507908

    210509455

    210509992

    210511033

    210513615

    210518239

    210518739

    210519453

    210519528 <

    210519749

    210519982 *

    210522494

    210523892

    210524041

    210524395

    210526473

    210527747

    210527925

    210528811

    210529424

    210529971

    210534263

    210534732

    210535170

    210535186

    210536061

    210536937

    210537905

    210538133

    210538598

    210538996

    210539287

    210542983

    210545912

    210545941

    210547105

    210549532

    210551045

    210552677

    210553304

    210553775

    210553950

    210555933

    210558216

    210560927

    210561994

    210562819

    210563003

    210563410

    210564081

    210564347

    210566008

    210566910

    210567516

    210567628

    210568200

    210568214

    210569604

    210569770

    210570358

    210574135

    210575024

    210576234

    210576774

    210577268

    210577632

    210578381

    210579563

    210581202

    210583507

    210587542

    210589260

    210589582

    210589916

    210591703

    210592463

    210593490

    210598655

    210598969

    210599217

    210599981

    210601109

    210604966

    210607190

    210607917

    210608165

    210609336

    210610446

    210610912

    210612142

    210614091

    210618915

    210619049

    210621461

    210623493

    210625450

    210625740

    210626041

    210626414

    210628286

    210628944

    210629497

    210629674

    210630718

    210632381

    210634464

    210635023

    210636169

    210640587

    210640966

    210643507

    210643901

    210645089

    210646763

    210646997

    210648519

    210651379

    210652508

    210652698

    210653483

    210654047

    210655159

    210658027

    210658415

    210659072

    210659555

    210661434

    210663503

    210664084

    210664901

    210665158

    210667556

    210670052

    210670134

    210672441

    210674207

    210674408

    210674692

    210674696

    210675130

    210675410

    210676192

    210678152

    210678194

    210681303

    210682270

    210682533

    210684978

    210688360

    210688461

    210688524

    210688580

    210688607

    210691271

    210691870

    210692324

    210693746

    210694695

    210695246

    210695955

    210695994

    210696161

    210696959

    210697132

    210697273

    210699081

    210700098

    210701183

    210701812

    210704133

    210704834

    210706205

    210706309

    210707287

    210707405

    210707436

    210707811

    210710183

    210710427

    210711227

    210712335

    210712367

    210715010

    210716480

    210718930

    210719272

    210720772

    210721708

    210723315

    210724061

    210724906

    210725453

    210730963

    210731765

    210732574

    210732952

    210734337

    210734852

    210738971

    210739039

    210740200

    210740523

    210740650

    210742030

    210742057

    210742242

    210742592

    210744092

    210744764

    210745240

    210745695

    210747190

    210747217

    210747390

    210747688

    210747698

    210747818

    210747837

    210747932

    210748025

    210748060

    210748446

    210749423

    210749850

    210749928

    210751234

    210751641

    210753975

    210754523

    210754849

    210754930

    210756714

    210756734

    210757163

    210757756

    210759564

    210760422

    210761053

    210761169

    210761838

    210762740

    210762863

    210762875

    210763921

    210764183

    210765795

    210766338

    210766884

    210769047

    210769333

    210769813

    210771355

    210771662

    210771734

    210772588

    210774635

    210774656

    210774807

    210775959

    210776021

    210776124

    210776486

    210776647 Numerous

    210776828

    210778066

    210780155

    210780532

    210780789

    210780956

    210780989

    210781239

    210781898

    210781990

    210783094

    210783336

    210784039

    210786758

    210786891

    210787202

    210788985

    210789456

    210789582

    210790491

    210791550

    210792153

    210792668

    210793045

    210793743

    210795330

    210796117

    210796402

    210798039

    210799434

    210799774

    210799959

    210800970

    210802674

    210804503

    210804526

    210808522

    210810145

    210811401

    210811598

    210813189

    210813671

    210814428

    210816085

    210816801

    210819083

    210819746

    210819978

    210820979

    210821360

    210822498

    210822691

    210822989

    210826892

    210828314

    210829886

    210829916

    210830104

    210830467

    210831310

    210831392

    210832378

    210832801

    210833622

    210834631

    210835395

    210837322

    210838970

    210839388

    210840966

    210841114

    210841434

    210843552

    210843635

    210846442

    210846736

    210847165

    210848323

    210849580

    210853239

    210853541

    210854050

    210854098

    210854408

    210855601

    210855718

    210856107

    210856207

    210857107

    210860152

    210862226

    210862422

    210863075

    210863316

    210865148

    210865372

    210865374

    210865655

    210866482

    210868974

    210869110

    210869266

    210870965

    210871724

    210872577

    210872849

    210872985

    210873256

    210874779

    210875952

    210876759

    210878635

    210879084

    210879553

    210879662

    210880558

    210880560

    210881103

    210883635

    210885018

    210885497

    210885995

    210886447

    210886867

    210888723

    210890552

    210891664

    210892321

    210892398

    210893326

    210893458

    210894441

    210894583

    210894955

    210896514

    210896547

    210898639

    210898971

    210901240

    210901283

    210904018

    210904850

    210905255

    210905854

    210906262

    210906299

    210907442

    210907840

    210907884

    210908248

    210909746

    210910007

    210910292

    210910448

    210911240

    210911601

    210915248

    210915269

    210915626

    210915695

    210916027

    210917578

    210918149

    210919084

    210919158

    210920246

    210920469

    210921969

    210922602

    210922662

    210922778

    210923615

    210924301

    210925598

    210926114

    210926194

    210926943

    210927253

    210927281

    210927331

    210928360

    210929228

    210930791

    210931244

    210933170

    210934047

    210934071

    210934634

    210934910

    210935548

    210936710

    210936757

    210936878

    210937628

    210939022

    210939323

    210939348

    210940436

    210940783

    210941338

    210941642

    210942652

    210942950

    210943453

    210943628

    210944661

    210944698

    210945054

    210945519

    210945938

    210946068

    210946427

    210946926

    210947280

    210947594

    210947895

    210948670

    210948982

    210949142

    210949534

    210949782

    210950389

    210951703

    210952298

    210953866

    210953918

    210954438

    210955775

    210956678

    210956967

    210957162

    210958195

    210959284

    210959901

    210963067

    210963351

    210963715

    210963935

    210964488

    210964557

    210965709

    210965731

    210966043

    210966902

    210966931

    210967582

    210967879

    210967901

    210968957

    210969307

    210970850

    210971138

    210972491

    210972551

    210973153

    210974053

    210974237

    210974893

    210976082

    210977645

    210978650

    210978953

    210979439

    210979486

    210981137

    210981388

    210982152

    210982278

    210982502

    210982519

    210982761

    210983090

    210983092

    210983198

    210986567

    210986927

    210987479

    210988354

    210988635

    210989061

    210989930

    210991032

    210991540

    210991949


    Posted

  • Martti_Holst_Kristiansen by Martti_Holst_Kristiansen

    EPIC 210363145 (P = 8.199). Phase-folded signal (see Vanderburg lightcurve for TTVs):

    enter image description here


    EPIC 210402237 (P = 10.998). Phase-folded signal:

    enter image description here


    EPIC 210558622 (P = 19.574). Phase-folded signal:
    enter image description here


    EPIC 210577548 (P1 = 6.421). Phase-folded:

    enter image description here

    EPIC 210577548 (P2 = 27.838). Phase-folded:

    enter image description here


    EPIC 210598340 (P = 3.732). Phase-folded signal:

    enter image description here


    EPIC 210629082 (P = 27.328). Phase-folded signal:

    enter image description here


    EPIC 210731500 (P = 9.729). Phase-folded signal:

    enter image description here


    EPIC 210775710 (P = 59.835). Phase-folded signal:

    enter image description here


    EPIC 210848071 (P = 41.691). Phase-folded signal:

    enter image description here


    EPIC 210956385 (P = 56.627). Phase-folded signal:

    enter image description here


    EPIC 210957318 (P = 4.098). Phase-folded signal:

    enter image description here


    EPIC 210958990 (P = 1.702). Phase-folded signal:

    enter image description here


    EPIC 210965800 (P = 8.746). Phase-folded signal:

    enter image description here


    EPIC 210968143 (P = 13.727). Phase-folded signal:

    enter image description here


    Posted

  • ajamyajax by ajamyajax

    Re 210363145: Martti, nice spotting on a smooth curve. Andrew's corrected data sure makes a difference. And agree this looks like another decent sub-Neptune planet candidate. The PC radius estimate shown is for a star ~0.85x R_sol.

    s1=2237.81 p1=8.199 d1=0.133 (3.20 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210363145 , 2MASS J03405481+1234216 , 10.384 , 9.910 , 9.799 , 0.474 , 0.111 , ('K2V', 0.85) , ('K4V', 0.78)

    au min-max 0.065 0.08

    stellar diameter in solar units min-max 0.67 0.885

    stellar mass in solar units min-max 0.545 1.015

    period in days min-max 8.199 8.21

    duration in hours min-max 3.0 3.234

    F1

    Posted

  • Martti_Holst_Kristiansen by Martti_Holst_Kristiansen in response to ajamyajax's comment.

    Thanks Mark, you are right they sure do. Also, good looking fit.

    Posted

  • zoo3hans by zoo3hans

    As usual I'm starting from the last one and I'm working toward Martti. (See also page 1 with results from the uncorrected data.)

    Planet Candidates:

    210968143 P=13.74 days. Nice candidate as Martti already pointed out in his list. So I stop here now. (also on page 1)

    210978317 Maybe etremely long transit (17 days) from 2256 to 2273.

    210991175 P=6.8578 days. Depth 0.005. Could be contamination by a BGEB, since small secondaries are visible.

    210996142 Dip at 2267.25.

    211002562 Period about 3.347 days. Nice Hot Jupiter. Depth 0.017. (also on page 1)

    211043772 Dip at 2262.79.

    211048999 P=5.17 days. Starting at 2233.6.

    211064647 Maybe transit/eclipse at 2273.97, rather V-shaped.

    211067990 Slight chance for a transit at 2293.93.

    211087003 Probably a multi-planet system. Good large transit at 2251.1, smaller transit at 2231.15, 2259.45, 2287.75. P=28.3 days.

    211089792 P=3.25875 days. It could be a typical Hot Jupiter. (also on page 1)

    211106187 P=14.65 days. Starting at 2239.27

    211108321 Dip at 2271.8.

    211110086 Maybe long transit around 2240.

    211133138 P=7.435 days. Starting at 2238.17. (also on page 1)

    211147528 P=2.348 days, starting at 2232.4. (also on page 1)

    211169300 P=16.45 days, first transit at 2234.8. (also on page 1)

    EB Candidates:

    210969614

    210974364 P=32.75 days, depth about 0.07.

    210975523 Dip at 2239.23. Depth 0.14.

    211000135

    211012889

    211015722

    211020446

    211036449 Eccentrical EB

    211038065 Eclipse at 2249.4.

    211041532 Nice eccentrical detached EB.

    211075893 Maybe eclipse at 2253.78.

    211075914 Eclipse at 2266.22, maybe secondary eclipse at 2237.14.

    211082420

    211093684 Interesting triple system candidate, regular V-shaped eclipses (with small secondary eclipses in between), but additional long eclipse/transit around BKJD 2251 (depth about 0.023) ! Maybe another tatooine?

    211096084 Maybe EB, depth is rather large (0.3).

    211099781 P=7.56 days, small secondary transits/eclipses can be seen. Depth about 0.02, i.e it could also be a Hot Jupiter (profile is rather U-shaped).

    211132787 Deep dips, must be an EB.

    211135350 Maybe additional transit at 2252.2.

    211147178 Nice detached EB

    211154046 Nice detached EB with relatively long period

    211155479 Eccentrical EB

    211160700

    211160717

    211182027 Probably semi-detached giant EB

    RR_Lyrae Candidates:

    210994946

    211048310

    211069540

    211069629

    DSCT/GDOR Candidates:

    210984540

    210999011 D

    211019860 D

    211053882 D

    211083721 D

    211115338 D

    211179336 D

    Others:

    210978953 Maybe asteroid crossing at 2290.46.

    211045231 Maybe asteroid crossing at 2256.5.

    211079830 Maybe asteroid crossing at 2274.6.

    Posted

  • ajamyajax by ajamyajax in response to zoo3hans's comment.

    Re 211169300: Dear Hans Martin all four transits seem to have different depths, so not sure what we can do with this one. (?)

    F1


    More importantly, Hans Martin: Your two WASP-47 planets were confirmed recently however, so hope that cheers up your weekend!

    http://exoplanetarchive.ipac.caltech.edu/docs/exonews_archive.html#08Oct2015

    Posted

  • ajamyajax by ajamyajax

    Re 210403955 from Martti's list: possibly three planet candidates here, including an uncommon small-ish super-Earth. Some transits there are partially blended so a star frequency or glitches or contamination as an explanation should be explored. But consistent stellar estimates I get anyway seem to support a planet. The star estimate used for these radii calcs is ~0.79X R_sol.

    s1=2233.49 p1=5.603 d1=0.115 (2.76 hours)

    s2=2244.616 p2=19.09 d2=0.16 (3.84 hours)

    s3=2249.955 p3=28.842 d3=0.19 (4.56 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210403955 , 2MASS J03560900+1333334 , 10.874 , 10.425 , 10.313 , 0.449 , 0.112 , ('K2V', 0.85) , ('K3V', 0.81)

    au min-max 0.05 0.06

    stellar diameter in solar units min-max 0.68 0.84

    stellar mass in solar units min-max 0.53 0.92

    period in days min-max 5.591 5.609

    duration in hours min-max 2.706 2.795

    au min-max 0.125 0.14

    stellar diameter in solar units min-max 0.69 0.81

    stellar mass in solar units min-max 0.715 1.005

    period in days min-max 19.081 19.097

    duration in hours min-max 3.751 3.93

    au min-max 0.175 0.185

    stellar diameter in solar units min-max 0.77 0.845

    stellar mass in solar units min-max 0.86 1.015

    period in days min-max 28.834 28.848

    duration in hours min-max 4.506 4.691

    T1
    T2

    F1
    F2
    F3

    Note two transit points between 2249.94 and 2249.97 BJD were corrected in this last fit for a possible glitch (or blending). See earlier transit close-up.

    Posted

  • Martti_Holst_Kristiansen by Martti_Holst_Kristiansen in response to ajamyajax's comment.

    Thanks Mark, another good looking fit! Btw, I originally flagged the C2 triple EB 😉, well too bad it was not published by PH.

    Posted

  • Dolorous_Edd by Dolorous_Edd in response to ajamyajax's comment.

    EPIC 210403955

    UKIRT image K-band

    enter image description here

    Posted

  • ajamyajax by ajamyajax in response to Martti Holst Kristiansen's comment.

    Re: "I originally flagged the C2 triple EB"

    Sorry Martti of course I should have looked all the way back and nice original find by you then. And as usual too. 😃

    Posted

  • zoo3hans by zoo3hans in response to ajamyajax's comment.

    Dear Mark

    this is a bit troublesome (about EPIC 211169300). And yes, WASP-47 is a really interesting system.
    Could you look into 211099781 ? I'm not sure if it's an EB or a warm Jupiter.

    Cheers, Hans Martin

    Posted

  • Martti_Holst_Kristiansen by Martti_Holst_Kristiansen in response to ajamyajax's comment.

    No worries Mark! And yes, not to forget, congratulations on WASP-47 c/d Hans Martin!

    As for EPIC 211099781, I think it is an EB (secondary periodic eclipses).

    Posted

  • ajamyajax by ajamyajax in response to zoo3hans's comment.

    Yes and with corrected data, the picture becomes a little clearer. As Martti mentioned there is a significant secondary we need to consider. An albedo effect is a possible cause for this however, so hopefully there is still a chance for a HJ here. The transit depth is also a bit of a concern though as you well know. But I've thought one or two of these were EB's before and SF says no it could be an HJ, so will try to remain hopeful here anyway.

    T1

    F2

    Note the duration was adjusted longer with this corrected data fit. And these transits were slighly malformed for whatever reason and were not included:

    [ 2231.335 to 2231.615 BJD]

    [ 2238.8993 to 2239.1793 BJD]

    [ 2246.4636 to 2246.7436 BJD]

    [ 2261.5922 to 2261.8722 BJD]

    [ 2299.4137 to 2299.6937 BJD]

    Posted

  • zoo3hans by zoo3hans

    EB candidate 211075893

    zoom into LC with LcViewer: (corrected K2-C4 data)
    LC1

    I think the rise in the middle of the feature occurs because of an over-correction.

    zoom into LC with Topcat: (raw K2-C4 data)
    LC2

    Posted

  • Shellface by Shellface in response to ajamyajax's comment.

    But I've thought one or two of these were EB's before and SF says no it could be an HJ, so will try to remain hopeful here anyway.

    That looks like an unblended EB (with a small stellar companion) to me. The eclipses are definitely too deep for a typical planet. Also, there appear to be ellipsoidal variations…

    That's a very clean transit signal, though, so I'll probably be able to do analytical stuff. And the star is probably a Pleiad, so it could be important for stellar models.

    Posted

  • ajamyajax by ajamyajax in response to Shellface's comment.

    Appreciate that help, thanks.

    Posted

  • ajamyajax by ajamyajax

    Re 211087003 from Hans Martin's list: and a nice find of two gas giant planet candidates around maybe a Sun-size star, too.

    As HM mentioned there is only one transit event visible for the second and larger transit, but I can guess its period at ~65 days (note a second event would be visible if that P ≤ 46.8). And this assuming ~0.95X R_sol and ~1.0X M_sol for the star. Also there could be a small albedo effect transit at the half-period interval as well, which might indicate a luminous planet if not a BGEB (heavens). The two observed could be coincidental dips in the flux however.

    Also the P=28.x object might be a Neptune-class planet while the P=65.x object might be a Saturn-class planet at ~9.x Re.

    s1=2231.17 p1=28.28 d1~=0.22 (5.26 hours)

    s2=2251.112 p2=46.8+ d2=0.29 (6.96 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    211087003 , 2MASS J03571948+2421331 , 10.596 , 10.294 , 10.227 , 0.302 , 0.067 , ('G3V', 1.0) , ('G0V', 1.09)

    au min-max 0.17 0.2

    stellar diameter in solar units min-max 0.88 1.07

    stellar mass in solar units min-max 0.82 1.335

    period in days min-max 28.272 28.274

    duration in hours min-max 5.209 5.386

    Semi-Major Axis a (A.U.) = 0.18165

    Stellar diameter ratio = 0.95

    Stellar mass ratio = 1.0

    Period ~= 28.28 days

    Duration ~= 5.26 hours

    Semi-Major Axis a (A.U.) = 0.318

    Stellar diameter ratio = 0.95

    Stellar mass ratio = 1.0

    Period ~= 65.5 days

    Duration ~= 6.96 hours

    Update: also noticed a slight dip in the flux at the half-period of P=63.8 (31.9 days), so if the larger object is luminous perhaps this is an albedo effect eclipse and ~63.8 days is the true period. Speculative, but the duration is similar to the transit's duration.

    Semi-Major Axis a (A.U.) = 0.31249

    Stellar diameter ratio = 0.95

    Stellar mass ratio = 1.0

    Period ~= 63.8 days

    Duration ~= 6.9 hours

    F1
    F2
    T1

    Posted

  • zoo3hans by zoo3hans

    210961508 seems to have a period of 0.3499375 days. Depth about 0.001. Maybe a corora burner planet or contamination by a BGEB.

    Posted

  • ajamyajax by ajamyajax

    Re 210508766 from Martti list: another possible MPC find I think because multiple BGEB signals in one LC are pretty rare. And my alternating fits were inconclusive. So to me, these transits look like two short-period, mini-gas giant planet candidates around a small M-Dwarf. There is some blending which is not uncommon with shallow transit objects whatever they might be. And the stellar estimate used for these plots is ~0.64X R_sol.

    s1=2231.3135 p1=2.7472 d1=0.08 (1.92 hours)

    s2=2233.275 p2=9.998 d2=0.12 (2.88 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210508766 , 2MASS J03593637+1533320 , 11.599 , 10.945 , 10.765 , 0.654 , 0.18 , M , ('M7V', 0.098) , ('K7V', 0.64)

    au min-max 0.03 0.035

    stellar diameter in solar units min-max 0.56 0.72

    stellar mass in solar units min-max 0.475 0.76

    period in days min-max 2.739 2.754

    duration in hours min-max 1.82 2.015

    au min-max 0.075 0.085

    stellar diameter in solar units min-max 0.59 0.71

    stellar mass in solar units min-max 0.565 0.82

    period in days min-max 9.981 9.996

    duration in hours min-max 2.783 2.977

    F1
    F2

    T1
    T2

    Note: technically, the 2253.3x BJD transit should have been removed because of transit overlap, but its effect should be minimal so I didn't this time.

    Posted

  • JKD by JKD

    210416676 - maybe a PC at 2263.73 BKJD

    Posted

  • JKD by JKD

    210421873 - 2 independent interesting signals at 2263.68 and 2266.84 BKJD

    Posted

  • Martti_Holst_Kristiansen by Martti_Holst_Kristiansen

    Unfortunately, I am quite confident that the events are glitches.

    Posted

  • Martti_Holst_Kristiansen by Martti_Holst_Kristiansen

    EPIC 211093684:

    New paper out today: HII 2407: A Low-Mass Eclipsing Binary Revealed by K2 Observations of the Pleiades

    Hans Martin, I thought that you initially mentioned something about a possible additional transit for this target, but somehow I can not find the post. Perhaps, I am wrong? Anyway, here is the event (Corrected Vanderburg lightcurve).

    enter image description here

    The feature is not present in C4 PDCSAP:

    enter image description here

    I used Troy's AKO-TPF tool and extracted the lightcurve. The primary and secondary EB signals can easily be seen but no signs of the aforementioned transit.

    enter image description here

    Posted

  • ajamyajax by ajamyajax in response to Martti Holst Kristiansen's comment.

    Yeah, looks like that is the case for the event at 2263.69 BJD. Regarding the other possible transit (2266.835 BJD) I don't see other mentions. Have you seen this region on other light curves as a glitch? I ask because if so, I want to remove my spec analysis post so it isn't a distraction from other better candidates we have here. (Edit: previous analysis of 210421873 removed)

    Posted

  • zoo3hans by zoo3hans in response to Martti Holst Kristiansen's comment.

    Dear Martti

    your memory serves you well, I wrote indeed on page 6 of this thread:

    211093684 Interesting triple system candidate, regular V-shaped eclipses (with small secondary eclipses in between), but additional long eclipse/transit around BKJD 2251 (depth about 0.023) ! Maybe another tatooine?

    Cheers, Hans Martin

    Posted

  • JKD by JKD

    210357078

    Transit signal at 2242.632 BKJD with

    Duration time min. 6.374 hrs and

    Flux min 579 ppm

    Posted

  • JKD by JKD

    210357523 - possible transit next to a glitch area

    Transit signal at 2250.131 BKJD

    Duration time min 4.90 hrs

    Flux min. 1235 ppm

    Posted

  • JKD by JKD

    210358034 - PC already mentioned by Martii on page 6

    No follow-up so far

    Transit at 2263.626 BKJD

    Duration Time 4.4.11 hrs (min)

    Flux 1342 ppm (min)

    Posted

  • JKD by JKD

    210364503 - Planet Candidate at

    2242.612 BKJD

    Transit duration 5.884 hrs

    Flux 4669 ppm

    Posted

  • ajamyajax by ajamyajax

    210448987: looks ok to me as a blended planet candidate with fairly consistent M-dwarf estimates. A star radius of ~0.64x R_sol used here.

    s1=2231.343 p1=6.1023 d1=0.10 (2.4 hours or so)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210448987 , 2MASS J03495652+1430080 , 12.048 , 11.419 , 11.316 , 0.629 , 0.103 , ('K7V', 0.64) , ('K2V', 0.85)

    au min-max 0.055 0.06

    stellar diameter in solar units min-max 0.595 0.675

    stellar mass in solar units min-max 0.595 0.775

    period in days min-max 6.098 6.108

    duration in hours min-max 2.351 2.442

    F1

    Posted

  • ajamyajax by ajamyajax

    211012889: really distinct alternating depth transits here, so this one must be a EB or BGEB.

    s1=2246.34 p1=0.8698 d1=0.05 (1.2 hours or more)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    211012889 , 2MASS J04145912+2310481 , 12.630 , 11.908 , 11.659 , 0.722 , 0.249 , ('M8V', 0.082) , ('M2V', 0.5)

    F1a

    Posted

  • Martti_Holst_Kristiansen by Martti_Holst_Kristiansen in response to ajamyajax's comment.

    Yes, I have seen the 2266.855 BKJD event quite a few times. I just found an example in which both signals are present:

    enter image description here

    Posted

  • Martti_Holst_Kristiansen by Martti_Holst_Kristiansen in response to zoo3hans's comment.

    Oh, hmm.. do not know how I could miss that. Thank you Hans Martin!

    Posted

  • ajamyajax by ajamyajax in response to Martti Holst Kristiansen's comment.

    Martti, thanks for posting an excellent example of those particular glitches. Since these one-time events can apparently be very transit-like in C4 (and perhaps earlier in K2), I'd better refrain from doing any more analysis on those. Sorry in advance for anybody hoping for a chart and a second opinion there.

    Posted

  • JKD by JKD

    210367322 - maybe a PC transit

    MdPt Time 2261.08 BKJD

    Duration Time 6.86 hrs

    Signal Depth 2443 ppm

    Posted

  • ajamyajax by ajamyajax

    210991175: alternating shallow transit depths so transit could be a BGEB as Hans Martin indicated.

    s1=2231.785 p1=6.8565 d1=0.10 (2.4 hours)

    s2=2235.21 p2=6.8565 d2=0.10 (2.4 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210991175 , 2MASS J04102315+2250018 , 8.497 , 8.243 , 8.192 , 0.254 , 0.051 , ('F9V', 1.14) , ('F3V', 1.43)

    T1

    Posted

  • JKD by JKD

    210385888 - potential PC

    Signal: 2247.25 BKJD

    Transit Duration: 5.39 hrs

    Signal Depth: 980 ppm

    Posted

  • JKD by JKD

    210386880 and 210386883 are obviously the same EB system (corrected)

    Posted

  • JKD by JKD

    210387006 - potential PC

    Signal: 2245.42 BKJD

    Transit Duration: 2.45 hrs

    Signal depth: 1448 ppm

    Posted

  • JKD by JKD

    210387553 - potential PC

    Signal: 2261.98 BKJD

    Transit Duration: 3.92 hrs

    Signal Depth: 1455 ppm

    Posted

  • ajamyajax by ajamyajax in response to JKD's comment.

    Good to know, JKD. Thank you.

    And I should have thought of this earlier, but just wrote a small program that looks for duplicate 2MASS entries in my color lists (just a quick list to scan for these). Here are the two JKD mentioned and a few other duplicates in the C4 data:

    210386880 , 2MASS J03453431+1309330 , 9.465 , 8.950 , 8.866 , 0.515 , 0.084 , 'K3V'

    210386883 , 2MASS J03453431+1309330 , 9.465 , 8.950 , 8.866 , 0.515 , 0.084 , 'K3V'

    210324184 , 2MASS J03594004+1128262 , 8.131 , 7.917 , 7.786 , 0.214 , 0.131 , 'F7V'

    210324198 , 2MASS J03594004+1128262 , 8.131 , 7.917 , 7.786 , 0.214 , 0.131 , 'F7V'

    210406345 , 2MASS J03363025+1336459 , 6.078 , 5.317 , 5.070 , 0.761 , 0.247 , 'M9V'

    210406347 , 2MASS J03363025+1336459 , 6.078 , 5.317 , 5.070 , 0.761 , 0.247 , 'M9V'

    210492943 , 2MASS J03575202+1517333 , 8.683 , 8.508 , 8.436 , 0.175 , 0.072 , 'F6V'

    210492962 , 2MASS J03575202+1517333 , 8.683 , 8.508 , 8.436 , 0.175 , 0.072 , 'F6V'

    210701669 , 2MASS J03545714+1823126 , 10.810 , 10.485 , 10.373 , 0.325 , 0.112 , 'G8V'

    210701688 , 2MASS J03545714+1823126 , 10.810 , 10.485 , 10.373 , 0.325 , 0.112 , 'G8V'

    210904552 , 2MASS J03545704+2127395 , 10.166 , 9.610 , 9.416 , 0.556 , 0.194 , 'K4V'

    210904564 , 2MASS J03545704+2127395 , 10.166 , 9.610 , 9.416 , 0.556 , 0.194 , 'K4V'

    211023597 , 2MASS J04020461+2320455 , 9.363 , 9.306 , 9.251 , 0.057 , 0.055 , 'A7V'

    211023618 , 2MASS J04020461+2320455 , 9.363 , 9.306 , 9.251 , 0.057 , 0.055 , 'A7V'

    Posted

  • davidbundy77 by davidbundy77

    EPIC 210512842 - APH0000q6k

    As spotted by Layman Sterms and Hildifons on "Talk" this star has possible transits every 5.87 days starting at BKJD 2234.1787.

    The transit duration is about 0.20 days and the depths of the clearest transits are about 0.0006.

    There is a fainter star visible on Aladin Lite at a distance of about 10´´.

    Posted

  • ajamyajax by ajamyajax in response to davidbundy77's comment.

    210512842: sure looks like a planet candidate find by true Planet Hunters here. : )

    Just my opinion of course, but the star appears to be smaller than our Sun. How much smaller is tough to pin down with the range in my quick estimates here. I went with a midrange value of ~0.75X R_sol in the chart, which yields a possible PC with a super-Earth radius around 1.34Re. There is always a chance this could be a BGEB, but didn't see much sign of that.

    And this system is also on four planetary-titled proposals which gives it more credence as a planet candidate, but of course also means we aren't the first to think that. However I hope a possible discovery is still a thrill for those who saw this transit.

    s1=2234.13 p1=5.8715 d1=0.11 (2.64 hours +/-)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210512842 , 2MASS J04012997+1537300 , 10.778 , 10.386 , 10.299 , 0.392 , 0.087 , ('K0V', 0.89) , ('G8V', 0.94)

    au min-max 0.05 0.06

    stellar diameter in solar units min-max 0.6 0.77

    stellar mass in solar units min-max 0.485 0.835

    period in days min-max 5.864 5.875

    duration in hours min-max 2.504 2.695

    **PROPOSAL # PI TITLE GO4007 **

    GO4007 Winn K2 Planet-Search Targets from the Draft TESS Catalog

    GO4029 Charbonneau Characterizing Small Planets and Stellar Jitter with the Combination of K2 and HARPS-N

    GO4033 Howard The Masses and Prevalence of Small Planets with K2

    GO4060 Coughlin Discovery and Vetting of K2 Exoplanets

    F1

    Update: 210512842 probably not a PC because a neighbor to 210512752 with a similar period transit. See my later post.

    Posted

  • ajamyajax by ajamyajax

    Re 210598340 from Martti's list: a classic planetary transit fit, but what is it? Well, the duration seems too long for the near-Sun size star the colors here suggest. But that could mean maybe another subgiant or giant star, which would be neat. The target certainly looks reddish in the Aladin Lite image.

    So let's look at the range of possibilities maybe: if the star were Sun-size, the transiting object could a HJ radius of ~12.3Re. At ~3.0X R_sol, the transiting object would be more like 36.9Re meaning another star at low impact (witnessing the flat transit).

    Also I looked but didn't see any RAVE data for this one to help with the possible giant. The transit does seem connected to stellar flux cycle which could be more of a stellar indication, but didn't see any obvious sign of a secondary. So always hoping for a nice HJ but in previous transits like this, I think we favored them as more likely to be stellar.

    s1=2233.825 p1=3.7345 d1=0.2375 (5.7 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210598340 , 2MASS J03472850+1656298 , 11.222 , 10.953 , 10.876 , 0.269 , 0.077 , ('G2V', 1.0) , ('G6V', 0.97)

    au min-max 0.06 0.075

    stellar diameter in solar units min-max 2.53 3.28

    stellar mass in solar units min-max 2.065 4.065

    period in days min-max 3.721 3.739

    duration in hours min-max 5.6 5.799

    F1
    Al1

    And note this transit event removed from the fit because of apparent glitches:

    2241.17525 to 2241.41275 BJD

    Posted

  • ajamyajax by ajamyajax in response to ajamyajax's comment.

    Update: aw shucks, I just remembered about the NEA search option that shows nearby stars, including EPIC numbers if there are any found. Turns out EPIC 210512842 is 8.03 arcsecs away from 210512752... And 210512842 is a brighter 12.106 Kep Mag star, while 210512752 is the dimmer 16.773 Kep Mag. And both light curves show the transit spotted separately on PH, with a very similar period of course. So, I was probably wrong about BOTH of these being possible planet candidates because it's unlikely a planet transit would contaminate another light curve. So my guess is the same background binary is causing these separate light curve transits because both are so shallow and blended. Sorry about that.

    Aladin Lite image of 210512842:

    AL1

    Posted

  • davidbundy77 by davidbundy77 in response to ajamyajax's comment.

    The two light curves are virtually identical. It looks like the signal from the brighter star has completely swamped the dimmer star. I am not giving up all hope yet.

    Posted

  • ajamyajax by ajamyajax in response to davidbundy77's comment.

    Fair enough. That seems like the best case for a planet candidate there, so hope you are right.

    Posted

  • ajamyajax by ajamyajax

    Re 210956385 from Hans Martin's and Martti's lists: only two events but they do appear similar, so this could be a sub-Saturn planet candidate if a smaller M-dwarf. ~0.72X R_sol used for these stellar estimates. Note there is a very bright ~6 Kep Mag star several arc-minutes away as seen in the Aladin Lite image. VSX identifier information also listed below. 2MASS is J03495506+2214390.

    s1=2232.417 p1=56.627 d1=0.225 (5.4 hours +/-)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210956385 , 2MASS J03495538+2217036 , 12.625 , 12.230 , 12.103 , 0.395 , 0.127 , ('K0V', 0.89) , ('K4V', 0.78)

    au min-max 0.235 0.275

    stellar diameter in solar units min-max 0.595 0.74

    stellar mass in solar units min-max 0.54 0.865

    period in days min-max 56.621 56.634

    duration in hours min-max 5.103 5.459

    F1

    AL1

    Name, AUID, Coords (J2000), Const., Var. type, Period (d), Mag. range

    NSV 15801, 000-BBG-296 03, 49 55.00 +22 14 39.0, Tau, ACV, 3.2509, 5.74 (0.01) U

    http://www.aavso.org/vsx/index.php?view=detail.top&oid=54236

    Posted

  • ajamyajax by ajamyajax

    210786627: looks like this one is contaminated by possible EB 210786891 (also pictured) which is only 28 arcsecs away per an NEA radius search.

    The ephemeris here was measured for 210786627 which matches both transits.

    s1=2232.325 p1=1.7178 d1=0.11 (2.64 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210786627 , 2MASS J03262216+1939563 , 11.011 , 10.447 , 10.325 , 0.564 , 0.122 , ('K6V', 0.7) , ('K3V', 0.81)

    T1C

    T1

    Posted

  • zoo3hans by zoo3hans in response to ajamyajax's comment.

    Thanks Mark.

    See also https://www.cfa.harvard.edu/~avanderb/k2c4/ep210956385.html

    Posted

  • JKD by JKD

    210388236 - PC - Planetary Candidate

    Transit at 2268.478 BKJD

    Transit Duration 8.82 hrs

    Signal Depth 2525 ppm

    Posted

  • JKD by JKD

    210389383 - looks like a regular EB

    Posted

  • ajamyajax by ajamyajax

    210903662 from Martti's list: ok well, doing what I can here and inspired by a V-shaped HJ transit confirmed in a recent paper (see below), and by limb darkening comments from our friend Meg in the past (see her PH blog), I am going to guess this could be a grazing HJ also. This short-period candidate basically looks mostly planetary except for the stellar shape of the fit, and that could be from a high impact transit plus limb darkening on the star. Edit: the transit could be related to the flux cycle which could favor this one being more stellar.

    There are some nearby stellar neighbors, but I check all four EPIC ID's that appear in a NEA search and none of them looked like a contaminating transit source. Of course another star in view still could be, but with a "quick" look you only get so much analysis you know. 😃 The possible PC radius estimate was measured for an also possible ~0.90X R_sol star.

    s1=2232.84 p1=2.4103 d1=0.09 (2.16 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210903662 , 2MASS J04001225+2126512 , 10.923 , 10.660 , 10.574 , 0.263 , 0.086 , ('G0V', 1.09) , ('G8V', 0.94)

    au min-max 0.03 0.035

    stellar diameter in solar units min-max 0.725 0.92

    stellar mass in solar units min-max 0.62 0.99

    period in days min-max 2.401 2.416

    duration in hours min-max 2.064 2.259

    ...

    "EPIC 204129699b, a grazing transiting hot Jupiter on an 1.26-day orbit around a bright solar like star"

    S. Grziwa, D. Gandolfi, Sz. Csizmadia, M. Fridlund, H. Parviainen, H. J. Deeg, J. Cabrera, A. A. Djupvik, S. Albrecht, E. B. Palle, M. Pätzold, V. J. S. Béjar, J. P. Arranz, P. Eigmüller, A. Erikson, J. P. U. Fynbo, E.W. Guenther, A. P. Hatzes, A. Kiilerich, J. Korth, T. Kuutma, P.Montanés-Rodríguez, D. Nespral, G. Nowak, H. Rauer, J. Saario, D. Sebastian, D. Slumstrup

    http://arxiv.org/abs/1510.09149

    and from NEA -- K2 Targets within search area:

    EPIC Number RA [decimal degrees] Dec [decimal degrees] Distance [arc sec] Kepler-band [mag] Campaign Number

    210903662 60.0511 21.4475 0.15 12.050 4

    210903817 60.0464 21.4498 17.69 11.444 4

    210904949 60.0561 21.4672 72.74 15.569 4

    210905255 60.0400 21.4719 95.24 16.219 4

    F1

    Posted

  • Shellface by Shellface in response to Shellface's comment.

    EPID 211099781: I don't really want to take the hours to explain all the details for a system which, as it turns out, isn't very "useful", so I'll cover things briefly:

    • Despite lying close to the Pleiades nucleus, the star does not align well with the Pleiades colour-magnitude diagram (which I took from this paper), so it is not a Pleiad. I later identified it as a background late-F - early-G subgiant, more likely on the earlier side do to the lack of rotational activity.
    • The lightcurve of the system shows a very clear phase curve with significant ellipsoidal and Doppler beaming components. I observe semi-amplitudes of Aellip = 317.7 ± 8.3 ppm and Abeam = 185.1 ± 8.3 ppm, where the errors are as given.
    • EXOFAST is able to model the transit lightcurve well, though it cannot account for the non-negligible effects of the companion mass on the transits. I can (roughly) account for them manually, however.
    • After crudely modelling for additional effects, I get rough mass and radius estimates of M ≈ 1.3 Msol, R ≈ 2.5 Rsol and m ≈ r ≈ 0.3 times solar, assuming that the ellipsoidal variations are correct.
    • However, the beaming amplitude disagrees with the above and indicates that q is lower; as Doppler beaming is largely relativistic, it is less likely to be incorrect than ellipsoidal variations. Doubly however, though, I cannot combine the beaming mass function with the transit-derived density and radius ratio to make realistic stellar parameters; I can only see this being resolved if there is a significant third light parameter, in which case the validity of the phase variation amplitudes is forfeit without information on the third light parameter.

    With a clean transit lightcurve and clear phase variations, plus a fairly bright star (V = 12.4), this is a favourable target for studies of low-mass companions in EBs, though there are apparent difficulties in solving the system parameters, which may or may not be resolvable with RV observations. However, as an undoubtable EB, it is not an interesting target for Planet Hunters, and as it is probably not a Pleiad, it is not as astrophysically interesting as I had hoped.

    Posted

  • zoo3hans by zoo3hans in response to ajamyajax's comment.

    EPIC 210609658 :
    210609658

    Well, the LC looks very much planetary to me. Bear in mind that C4 has the Pleiades and other young stars in its field. So maybe the star is actually a very low mass star (say 0.1 M_sol) with still a large radius. For example I could get a soultion like:
    enter image description here

    Posted

  • ajamyajax by ajamyajax in response to zoo3hans's comment.

    Well, I have several questions about this: is a 0.1 Msun/1.28 Rsun ratio even possible outside of a red giant? I mean I can get the same theoretical results as you in my calculations, but for example would a pre-main sequence star like this even be visible? The field is definitely DSS-colored red in Aladin Lite including this star.

    Also about the possible planet, how would a gas giant get so close "so fast" if this is a young star? I thought migration in from colder regions was the prevailing theory on how hot Jupiters come to be. But what you propose is definitely a stimulating idea and I hope you are right because it could be an important observation. I need to do more research though in both areas and hopefully find other examples to support your argument. (Edit: what I am saying is, I just don't know yet.)

    Posted

  • zoo3hans by zoo3hans in response to ajamyajax's comment.

    Well, this is all wild speculation on my part, but it seems that young stars are bigger and cooler than normal stars, see for example http://arxiv.org/abs/1505.02446 . If a raduis of more than 1 R_sol is plausible I have no idea.
    Another possibility could be an opaque accretion disk around the star with a radius of 1-3 R_sol, although I would expect more variablity in the LC in such a case (as in a T-Tauri star).

    Posted

  • Shellface by Shellface

    A mass of 0.1 Msol is extremely fanciful. Pre-main-sequence masses at a given spectral type are generally similar to that of a main-sequence star of the same spectral type, so I disagree strongly with a 0.1 Msol mid-K PMS star.

    The star lies in the bottom-right of Taurus, which is not a region with a known PMS population to my knowledge.

    I can roughly estimate the stellar density to be ~5% of solar from the transit length, which is more compatible with a K-subgiant than a pre-main-sequence K star. For a mass of 1.3 Msol, R ≈ 3.0 Rsol. That would give r ≈ 0.2 Rsol, which is most likely stellar.

    I'll probably run this through EXOFAST later, but this looks like a very-low-mass stellar companion to me.

    Posted

  • Shellface by Shellface in response to ajamyajax's comment.

    EPID 210957318: This target was pointed out early on as a Hot Jupiter candidate. Though the transits appear to be on the narrow side, the lightcurve looks reasonably good to the eye.

    The star has some good quality photometry, even though it is relatively faint (V = 13.5, Kep = 13.2). These give a spectral type of ~K3, with an error of less than 1 subtype. Its significant proper motions of [25.9, -13.6] ± [2.3, 2.4] mas/yr indicate that the star is a dwarf, as an evolved star of such late spectral type and low brightness would have to lie very distant, and would struggle to reach such proper motions.

    There are two notable nearby stars that are brighter than the target, EPID 210956759 and EPID 210956858. However, they both lie ~30" away from EPID 210957318, which makes it unlikely that either contributes a significant amount of flux; indeed, both other stars have data availability, and both show no traces of the transits. Additionally, none of the stars have compatible proper motions to high significance, so none of them are gravitationally bound. Searching the 2MASS PSC reveals no other stars within 10", so blending is largely excluded, and can only be due to a star within a couple of arcseconds of the target.

    The out-of-transit lightcurve is mainly composed of a slow trend, which is likely to be at least partially systematic. The lack of identifiable rotational variability suggests the host star is old, as it implies either low-amplitude or long-period variability. This is particularly valid as K-dwarfs are typically strong rotational variables, with semi-amplitudes of something like 1%.

    I detrended the photometry as usual, and fed it to EXOFAST with a prior on Teff of 4900 ± 150 K and an unconstraining Fe/H prior. Without particular constraint to the density-related parameters, this was the resulting model:

    The good matches between the fitted stellar parameters and the stellar spectral type are clear without additional priors, supporting the association of the transits to the target (note that the Fe/H is not physically constrained, and models with Fe/H >0.2 result in only slight parameter changes). The clean transit shape is also visible. The short transits lead to a necessary high impact parameter, though the good resolution of ingress/egress means that b is well constrained to ~0.65, hence this does not strongly influence the modelled stellar parameters.

    Though the companion appears to be small for a Hot Jupiter - which are almost characteristically inflated above their expected radii - this is likely impacted upon by its relatively low equilibrium temperature. Indeed, for Hot Jupiters with Teq ≈ 1000 K, a radius of ~1.0 Rjup is in fact fairly average. This can be construed as support for the planetary interpretation of the companion, though I would caution against taking this very strongly.

    Overall, this is a convincing clump Hot Jupiter around a fairly cool star. With an expected RV semi-amplitude of >30 m/s, follow-up is very possible despite the relatively faint host. Though perhaps fairly mediocre compared to known planets, this is still one of K2's few new Hot Jupiter candidates, and is a favourable target for further observation. Planet candidate / probable planet.

    Posted

  • ajamyajax by ajamyajax in response to Shellface's comment.

    SF: regarding 210609658, is an inflated hot Jupiter puffed up by an older subgiant possible here? Just noticed this recent Kelt survey paper where a HJ of 1.699 R_jup and 0.902 M_jup was reported discovered. I wondered if this period/distance might be a bit too great for such inflation, but took a look at NEA confirmed planets and (edit: corrected) Kepler-435 has a P=8.6x and is 1.99 R_jup and its star is said to be 1.538 M_sol and 3.21 R_sol. Just a thought, is all.

    "KELT-4Ab: An inflated Hot Jupiter transiting the bright (V~10) component of a hierarchical triple"

    http://arxiv.org/abs/1510.00015

    Posted

  • Shellface by Shellface in response to ajamyajax's comment.

    I'd say the possibility is worth considering, but ~2 Rjup is at the extreme upper tail of the planetary radius distribution, hence why I said "most likely stellar". Though, after all, K-subgiants are pretty luminous, and subgiant evolution is fairly quick, so there's some possibilities. Still, let us merit caution.

    Like I said, I'll look at this analytically later. Probably next.

    The Pleiades seems to have been drier than I had hoped, unfortunately. Perhaps all the rotational activity masks shallow signals?

    Posted

  • jiipee by jiipee

    EPIC210960330, 2mass id: 04032022+2220488

    Quite obvious transit at approx. d 21.25-21.9 (Q1-2)
    link

    DSS seems ok, not likely contaminated. However, this is a variable star, which is rather interesting, if confirmed planet

    Posted

  • ajamyajax by ajamyajax in response to Shellface's comment.

    And this one could be near 2 Rjup, based on my quick fit of two transits anyway... This using your estimate of 3.1 R_sol. Another approximation of course, but my theoretical orbit calc below that works around these numbers as well. So looking forward to your closer look, whenever you have the time of course (no hurry).

    F11


    Semi-Major Axis a (A.U.) = 0.1278

    Stellar diameter ratio = 3.105

    Stellar mass ratio = 1.39

    Period ~= 14.15 days

    Duration ~= 12.24 hours

    Posted

  • ajamyajax by ajamyajax in response to jiipee's comment.

    Re 210960330 from Jiipee and other Planet Hunters: just an opinion of course, but this one is tricky because the possible transits could be anything.
    There are two events that are close in duration however, but the stellar estimates I get make those difficult to suggest as maybe planetary. So my best guess is maybe an eccentric EB, assuming the second repeat of this possible secondary is landing on a glitch area. Sorry I couldn't do any better for you here.

    s1=2239.10 p1=32.38 d1=0.45 (10.8 hours)

    s2=2246.72 p2=32.38 d2=0.38 (9.12 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210960330 , 2MASS J04032022+2220488 , 6.570 , 5.701 , 5.450 , 0.869 , 0.251 , ('L1V', '...') , ('M2V', 0.5)

    au min-max 0.24 0.275

    stellar diameter in solar units min-max 2.23 2.6

    stellar mass in solar units min-max 1.76 2.645

    period in days min-max 32.371 32.387

    duration in hours min-max 10.705 10.899

    T1

    Posted

  • zoo3hans by zoo3hans in response to ajamyajax's comment.

    EPIC 210960330 : s1 seems plausible, s2 does definitely NOT work, especially around 2279.

    Zooms into LC:

    z1

    z2

    and

    z3

    z4

    Posted

  • Shellface by Shellface in response to ajamyajax's comment.

    This star is definitely an M-giant, as it's far too bright to be a dwarf at its spectral type. The vigorous rotational activity indicates this is an unblended EB of some sort, though without a good radius estimate it's difficult to say how large the companion is.

    Posted

  • ajamyajax by ajamyajax

    *** Update: 210483889 looks contaminated by eccentric EB 210484192 -- see later post and charts ***

    Re 210483889: this PH pick has a V-shaped transit and looks stellar. The fit depth would be about 15.6Re using a 0.93x R_sol star estimate.

    http://talk.planethunters.org/#/subjects/APH0000pqd

    s1=2236.075 p1=7.196 d1=0.14 (3.36 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210483889 , 2MASS J03540357+1508137 , 11.630 , 11.013 , 10.886 , 0.617 , 0.127 , ('K6V', 0.7) , ('K4V', 0.78)

    au min-max 0.07 0.08

    stellar diameter in solar units min-max 0.895 1.08

    stellar mass in solar units min-max 0.885 1.32

    period in days min-max 7.186 7.202

    duration in hours min-max 3.264 3.456

    F1

    Posted

  • ajamyajax by ajamyajax in response to ajamyajax's comment.

    Update: 210483889 looks contaminated by eccentric EB 210484192, only 16.65 arc seconds away:

    from NEA, K2 Targets within search area:

    EPIC Number RA [decimal degrees] Dec [decimal degrees] Distance [arc sec] Kepler-band [mag] Campaign Number

    210483889 58.5149 15.1372 0.20 13.519 4

    210484192 58.5140 15.1417 16.65 8.894 4 (P=7.19632)

    210482444 58.5169 15.1110 94.41 18.017 4

    T1eb
    T1

    Posted

  • Ptd by Ptd

    http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001amu

    EPIC 210961508

    Toasty little number here, nice spot by several people, it maybe has friends.

    Posted

  • ajamyajax by ajamyajax

    Just a note here that 210678858 a possible C4 MPC:

    http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001ap1?page=1&comment_id=56708ce47af8593a46000427

    Posted

  • Dolorous_Edd by Dolorous_Edd

    EPIC 210908968

    Possible PC

    http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH000199y

    Posted

  • ajamyajax by ajamyajax

    Re 210958990 from Martti's list: fairly deep transit so probably a binary, but a chance for a hot Jupiter if a 1.0x R_sol star. There could be a secondary however.

    s1=2232.79 p1=1.702 d1=0.095 (2.28 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210958990 , 2MASS J04110096+2219311 , 11.143 , 10.843 , 10.709 , 0.3 , 0.134 , ('G3V', 1.0) , ('K6V', 0.7)

    au min-max 0.025 0.03

    stellar diameter in solar units min-max 0.9 1.18

    stellar mass in solar units min-max 0.715 1.255

    period in days min-max 1.694 1.711

    duration in hours min-max 2.18 2.376

    From NEA, K2 Targets within search area:

    EPIC Number RA [decimal degrees] Dec [decimal degrees] Distance [arc sec] Kepler-band [mag] Campaign Number

    210958990 62.7540 22.3253 0.16 12.613 4

    210958453 62.7373 22.3165 64.12 12.672 4

    F1

    Posted

  • ajamyajax by ajamyajax

    Re 210965800 from Martti's list: identified as HAT 259-0002667 on VSX (see below). Seems like the transit could be a possible sub-Neptune candidate if not a star spot etc. 0.80x R_sol estimate.

    s1=2237.34 p1=8.747 d1=0.13 (3.12 hours)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210965800 , 2MASS J03313333+2226055 , 10.786 , 10.426 , 10.292 , 0.36 , 0.134 , ('G8V', 0.94) , ('K6V', 0.7)

    au min-max 0.075 0.085

    stellar diameter in solar units min-max 0.73 0.875

    stellar mass in solar units min-max 0.735 1.07

    period in days min-max 8.75 8.751

    duration in hours min-max 3.031 3.218

    From NEA, K2 Targets within search area:

    EPIC Number RA [decimal degrees] Dec [decimal degrees] Distance [arc sec] Kepler-band [mag] Campaign Number

    210965800 52.8889 22.4349 0.12 12.134 4

    210965666 52.8502 22.4326 128.98 15.825 4

    Per VSX:
    Dist. ' Name AUID Coords (J2000) Const. Var. type Period (d) Mag. range

    0.00 Variable HAT 259-0002667 -- 03 31 33.33 +22 26 05.6 Tau ROT 8.68712507 10.79 J (0.022r)

    ROT: "Spotted stars that weren't classified into a particular class. All the SPOTTED stars in the UNSW list and the very small amplitude spotted stars found by Kepler are included here. Also, some stars that don't fit the current subtypes due to their physical properties have been classified as such (brown dwarfs and white dwarfs with spots). It may be used as a subtype when a T Tauri star shows rotational variability (TTS/ROT, CTTS/ROT or WTTS/ROT)."

    F1

    Posted

  • Dolorous_Edd by Dolorous_Edd

    Posted skyview images for number of candidates

    List WIP (not complete! will be updated )

    EPIC 210775710 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001b1b

    EPIC 210960330 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001apr

    EPIC 210403955 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001apq

    EPIC 210968143 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001ap5

    EPIC 210402237 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001am7

    EPIC 210956385 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001amq

    EPIC 210903662 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001amv

    EPIC 210448987 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001aor

    EPIC 210957318 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001aoi

    EPIC 211147528 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001akl

    EPIC 210605073 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001ao7

    EPIC 210961508 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001amu

    EPIC 210750726 - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH000113d

    Posted

  • zoo3hans by zoo3hans in response to Dolorous_Edd's comment.

    Thanks DE

    appreciated, as always.

    Posted

  • Dolorous_Edd by Dolorous_Edd in response to zoo3hans's comment.

    Thanks, hope at least some of them will be helpful

    Posted

  • Dolorous_Edd by Dolorous_Edd

    EPIC 211002562

    There is a small star visible to the NW

    UKIDSS K-band 1'x1'

    enter image description here

    Posted

  • Dolorous_Edd by Dolorous_Edd

    EPIC 211099781

    A companion can be seen in both the UKIDSS and CFHT image less than 2" away

    CFHT I2-band

    enter image description here

    Posted

  • Dolorous_Edd by Dolorous_Edd

    EPIC 210389383

    UKIDSS K-band 1'x1'

    Clearly seen companion to the SW

    enter image description here

    Posted

  • Dolorous_Edd by Dolorous_Edd

    EPIC 210558622

    UKIDSS K-band

    1'x1'

    enter image description here

    Posted

  • Dolorous_Edd by Dolorous_Edd

    EPIC 210568002

    UKIDSS k-band

    1'x1'

    enter image description here

    Posted

  • Dolorous_Edd by Dolorous_Edd

    EPIC 210957318

    In addition to UKIDSS - http://talk.planethunters.org/#/boards/BPH0000005/discussions/DPH0001aoi

    Was imaged by Subaru telescope W-S-R+

    enter image description here

    Same with different color scaling

    enter image description here

    Posted

  • Dolorous_Edd by Dolorous_Edd

    EPIC 211089792

    UKIDSS K-band

    1'x1'

    Clearly seen close companion

    enter image description here

    Posted

  • Dolorous_Edd by Dolorous_Edd

    EPIC 210780851

    UKIDSS K-band

    1'x1'

    Close companion can be seen to the NE

    enter image description here

    Posted

  • Dolorous_Edd by Dolorous_Edd

    EPIC 210819089

    UKIDSS 1'x1'

    K-band

    If binary , at least not visual

    enter image description here

    Posted

  • ajamyajax by ajamyajax

    210389383 revisited: looks more like an EB by transit depth with Huber/NEA value of 1.46 R_sol.. And as was previously mentioned there is a secondary present also. It has an eccentric transit which indicates a binary as well.

    s1=2236.77 p1=14.089 d1=0.254 (6.10 hours +/-)

    EPIC, 2MASS, J mag, H mag, K mag, J - H, H - K, (J-H spectral type, stellar mass est) (H-K spectral type, stellar mass est)

    210389383 , 2MASS J04102487+1313037 , 11.257 , 10.905 , 10.772 , 0.352 , 0.133 , ('G8V', 0.94) , ('K6V', 0.7)

    Semi-Major Axis a (A.U.) = 0.12

    Stellar diameter ratio = 1.46

    Stellar mass ratio = 1.16

    Period ~= 14.08 days

    Duration ~= 6.1021 hours

    From NEA, K2 Targets within search area:

    EPIC Number RA [decimal degrees] Dec [decimal degrees] Distance [arc sec] Kepler-band [mag] Campaign Number

    210389383 62.6037 13.2177 0.10 12.752 4

    210390632 62.6122 13.2463 107.17 10.519 4, HD 286545 -- Star on Simbad, Proper motions mas/yr: 28.5 -1.1, Spectral type: F5

    epic_number,tm_name,ra,dec,k2_teff,k2_rad,k2_mass,k2_kepmag,k2_pmra,k2_pmdec,k2_dist

    210389383,2MASS J04102487+1313037,62.603675,13.217711,6111.00,1.46,1.16,12.752,13.800,2.200,458.90

    210390632,2MASS J04102693+1314465,62.612210,13.246251,6187.00,1.70,1.26,10.519,28.500,-1.100,228.50

    F1MC

    Posted

  • ajamyajax by ajamyajax

    Also note the different depths of the primary transits in the more corrected data... This just to demonstrate that while those algorithms provide wonderful clarity to the K2 data, they do at times affect transits. Minimally corrected data can sometimes provide a more neutral view, especially of deeper binary transits as shown in my MC data fit of the previous example (210389383).

    T1MAST
    T1AIGRAIN
    T1MARK

    Posted

  • Artman40 by Artman40

    http://arxiv.org/abs/1606.05812

    EPIC 210363145. It's a mini-neptune orbiting a K-star and is located near Pleiades. Lack of planet detections in Pleiades itself and subsequent transit insertion simulations indicate that it's not easy to detect planets in Pleiades.

    Posted

  • Shellface by Shellface in response to ajamyajax's comment.

    EPID 210780851: At a glance this appears to be a giant planet candidate, but as others have observed the lightcurve exhibits shallow eclipses, so the companion cannot be planetary. Still, the companion must be small and the lightcurve has excellent signal-to-noise, so it is worth inspecting the system more closely to see what can be said.

    There seems to be an unusual disagreement between the colours of the target. To compare the indices and their implied spectral types:

    B-V = 0.529 ± 0.072: F8 ± 3

    J-H = 0.346 ± 0.043: G8 ± 4

    V-K = 2.299 ± 0.049: ~K2.5 ± 0.5

    It seems that either the Johnson indices are too bright, or the 2MASS indices are too faint. Edd has pointed that there is a companion at ~1-2", but it looks too faint to explain the above discrepancies.

    The Huber et al. Teff is 6149 ± 148 K, with a reddening of E(B-V) = 0.19. Though reddening is non-negligible in the area this value seems to be too large, and the Teff would be inconsistent with the unreddened B-V. Thus, I assume a preliminary value of Teff = 5700 ± 400 K that is intermediate of those implied by the spectral types, and indicate that this is susceptible to revision.

    There are no stars within 20" in the EPIC or the 2MASS PSC. Though Edd has pointed out a companion too close to be detected by either, with limited information it is not possible to discuss its nature. As it appears to be faint I choose to assume it has negligible effect on the primary, though this may not be entirely valid.

    The lightcurve is dominated by a systematic trend, as per usual. Below this there is some low-frequency variability which may be rotational. Though it is difficult to to determine the period because the amplitude is low (~200 ppm), it appears to be close to the orbital period at 15.78 days. This may be indicative of tidal interaction between the components.

    I detrended the lightcurve for transits and eclipses in the usual manner. The EXOFAST fit to the transits, assuming zero eccentricity and with Teff = 5700 ± 400 K as a prior, is shown below:

    The impact parameter is well-constrained, owing to the good resolution of ingress. Thus the fitted a/R is likely precise, which means that the low host density is probably real, even without modelling a non-zero companion mass and assuming e = 0. The host star is probably leaving the main sequence, though its radius is not currently that large.

    The companion radius is likely within a few decimal places of 1.8 Rjup, for a modest error on R. This is too large to be planetary at its moderate insolation, so a stellar companion is preferred even without considering the eclipse.

    The photometric rms is 80 ppm, which is quite low for the system brightness (Kep = 12.2, V = 12.5). This appears to be compatible with photon noise, indicating that there is little high-frequency variability.

    The eclipse profile, phased to the transit time and period, is shown below:

    There is some excess variability in the eclipse depth, which is likely due to the processing algorithm being unable to detect the eclipses a priori and subsequently over-aggressively detrending them. It is thus difficult to evaluate the true depth of the eclipse, so I assume a conservative value of 300 ± 100 ppm.

    EXOFAST gives the eclipse time as (BJD-2454833) 2240.5447 ± 0.0014 and the eclipse duration as 0.236 ± 0.007 d. As can be seen in the above figure there is a small-but-significant offset between the eclipse and phase 0.50, indicative of a non-zero eccentricity.

    Following (T(2)-T(1))/P = Φ, the phase of the eclipse is Φ = 0.51729 ± 0.00009. Then, by using the following equation:

    e cosω = π · (Φ-0.5)/(1+cosec²(i)), where ω is the argument of periastron for the companion

    Assuming i = 88.7 ± 0.3° (itself assuming b = 0.45 ± 0.10 and a/R = 20.3 ± 0.5), e cosω = 0.02717 ± 0.00014. Though omega cannot be directly constrained by this value, under a random distribution for ω there is an 82% probability that e < 0.1, so it can already be assumed that the orbital eccentricity is low.

    e sinω can be constrained by the following:

    e sinω ≈ (1-x)/(1+x), where x = D(2)/D(1), the ratio of eclipse duration to transit duration

    For x = 0.927 ± 0.029, e sinω ≈ 0.038 ± 0.016. Since we now have two equations for e and ω, it is possible to solve for both values; the results are e ≈ 0.047 ± 0.013 and ω ≈ 54.4 ± 12.3°, with e α ω (i.e e is highest when ω is largest, and vice-versa).

    From this, most of the parameters of the orbit have been solved from the photometry alone. Only the semi-major axis remains unknown due to the unknown system mass, though it is still determinable in a relative sense. This shows the power that eclipses have on the determination of system parameters, where they are detectable.

    When an eclipse is total, and assuming the two components are the only significant sources of flux in the lightcurve, the luminosity ratio of the components follow the equation:

    L(2)/L(1) = δ(2)/(1-δ(2)), where δ(2) is the eclipse depth.

    Note that as δ(2) -> 0, 1-δ(2) -> 1 so δ(2) -> L(2)/L(1). For an eclipse depth of 300 ± 100 ppm, L(2)/L(1) = 0.0003 ± 0.0001.

    Consider the modified Stefan-Boltzmann Law, L = 4πR²σT⁴. In the case of a ratio between two stars:

    L(2)/L(1) = (R(2)/R(1))²(T(2)/T(1))⁴

    L(2)/L(1) = (R/r)²(T(2)/T(1))⁴

    (r/R)² is equal to transit depth for low impact parameter, and as demonstrated above L(2)/L(1) is an eclipse derivable. Thus, for small L(2) and low impact parameter:

    δ(2)/δ(1) ≈ (T(2)/T(1))⁴, i.e the ratio of eclipse depth to transit depth is equal to the temperature ratio of the components to the fourth power.

    Since L(2) is small and b is low, the approximation is valid here. For δ(2)/δ(1) = 0.0003 ± 0.0001, T(2)/T(1) = 0.363 ± 0.031; for Teff(1) = 5700 ± 400 K, Teff(2) = 2069 ± 322 K. I suspect this is an underestimate - it lies within the BD range, but r seems to be too large for that to be true - though nevertheless it does clearly indicate that the companion lies towards the bottom of the main sequence.

    To conclude, this is a binary consisting of a late-F - early-G primary with a very late-type secondary with a slightly eccentric orbit. This system is a good example of how much can be derived from an EB lightcurve even when the companion approaches planetary size, and hopefully shows what will be routinely possible when photometry reaches a level when the detection of planetary eclipses becomes commonplace.

    I chose this system in particular because it is quite bright, at V = 12.5. Those who may be interested in characterising a very-low-mass star with reasonably long period would find this a useful target, as determination of its mass should be possible with only a few RVs.

    Posted

  • Shellface by Shellface in response to zoo3hans's comment.

    EPID 210945342: This is a unique system. Even though it is difficult to model analytically, I will attempt to infer its nature.

    The most obvious feature of the lightcurve is the enormous rotational signal. With a semi-amplitude of ~12% it is far larger than the rotational variability seen on any normal star. Next come the transits and eclipses; at ~3% and ~1% they are shallow for an EB. They also phase consistently with the rotational signal; the equality between the orbital and rotational periods show that the primary is tidally locked to the secondary, which usually only occurs when the masses are similar. Third is the most unusual part, the extremely odd transit profile. All of the transits show a large "spike" just before the mid-transit, which can very clearly be seen when the transits are phase-folded:

    The orange line marks what might be expected of a "normal" transit (please excuse the slight offset from phase 0.5). The variability around the peak is real and acts transit-to-transit, indicative of some temporal variability in the phenomenon. On the other hand, the phase of the brightening is very consistent, so the brightening occurs at the same time relative to every transit.

    The most logical cause for this phenomenon, as zoo3hans indicated, is a large spot. When a transiting object crosses a starspot, a magnetically complex cool area on the stellar surface, the amount of light blocked by the companion decreases as spots emit less light than the rest of the surface, so there will be a positive bump in the transit. Spot crossings have been observed during transits of stars and planets alike, but I am not aware of anything as large as this.

    Spot crossings are compatible with the observed rotational signal, as well. The large amplitude of the variability indicates the spot(s) moving across the star are proportionally large, compatible with the large bump in the transit profile; the transits always occur just prior to the minimum of the rotational period, so the spots should be slightly offset from the centre of the stellar disk, and indeed the brightening always occurs slightly before the mid-transit time. One can imagine a system architecture something like the mockup shown below:

    I am not aware of any expression that relates rotational amplitude to spot size, so the depicted size is a guess. The companion radius, however, should be reasonably accurately scaled even when considering the somewhat indeterminate transit depth (δ between 0.04 and 0.05 gives r/R between 0.2 and 0.22, and I chose δ = 0.045).

    What can be said of the types of the components? The colours of the object give a (reddened) spectral type of ~K7, and the long transits indicate the primary is a giant. The Huber et al. parameters seem to peg the star as a bright giant (class II), but the transit length implies a density more like a regular giant (class III). Regardless of the exact nature of the primary, evolved stars are habitually magnetically quiet, so the large rotational amplitude is undoubtedly due to the companion.

    Using the expression for temperature ratio used in the above comment, T(2)/T(1) in this system appears to be ~0.70 ± 0.04, most of the uncertainty stemming from the poorly determined true radius ratio. For Teff(A) of, say, 4500 ± 200 K, Teff(B) = 3150 ± 350 K, which is ~mid-M in spectral type; the companion is probably an M-dwarf.

    Though it is difficult to parameterise a giant with what little information is available, with a transit density of ~0.1 g/cm^3 the companion radius r comes out as ~0.5 Rsol even for a low primary mass of 1.0 Msol. This is at about the highest value allowed by the temperature range for an M-dwarf, so the results are roughly consistent. M = 1.0 Msol would imply a system age of ~11 Gyr; though this seems unlikely, the Huber et al. metallicity is very low, which tentatively suggests the star is around this old. A more proper determination of the system parameters would depend on follow-up observations.

    It would probably take some dedicated modelling to get good parameters from the lightcurve, because I have never seen such an extreme case of starspot crossings. Still, despite the difficulty, this is a very unusual system that deserves some proper attention.

    Posted