Planet Hunters Talk

KID 201205007 - APHC0120143

  • zoo3hans by zoo3hans

    KID 201205007 appears to have a single transit at BKJD 2030.35 , as JKD had pointed out in page 4 of http://talk.planethunters.org/#/boards/BPH0000007/discussions/DPH00008nt

    Posted

  • zoo3hans by zoo3hans

    Slightly detrended light curve:

    enter image description here

    Posted

  • zoo3hans by zoo3hans

    Zoom into light curve around BKJD 2030.35

    enter image description here

    larger zoom:

    enter image description here

    Posted

  • zoo3hans by zoo3hans

    Transit duration is about 5.5 hours, depth about 0.002 mag. Assuming a 0.5 R_sol star, I would get a 2.5 R_Earth planet with a period around 100 days (very rough estimates only).

    Posted

  • ajamyajax by ajamyajax

    201205007: well my idea here probably a longshot but if a period around 43.7 days works for this star, maybe an earlier transit could be at the 1986.5x BJD glitch area. Looked at the aperture data but saw no sign of it though. However another system with that situation (201577035; see earlier PH comments) had a transit that was basically erased by a glitch and/or correction at this location.

    So maybe:

    s1=1986.69 p1=43.696 d1=0.25 (6.0 hours or less)

    Posted

  • zoo3hans by zoo3hans

    Dear Mark

    an interesting idea. Although in our case here I think there are not enough pixels affected at BKJD 1986.5. I expect 11 pixels and only 6 or 7 could be masked I think. So I prefer a longer period around 100 days or so (depending on the size of the host star which I don't know).

    enter image description here

    larger zoom:

    enter image description here

    Posted

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

    HM: I should have done this earlier, but put together a period estimating routine also. And guess what, I get both our estimates just by changing the AU and the star ratios compared to the Sun. So I suppose to get any further with this one, we need to try to find out more about this star if possible. I looked for a UKIRT or SDSS image but couldn't fine either. There is SkyView data, but only a few stars in the area for any reference help.

    Also you are right about the pixel count being less for the glitch area here. But in the other example the glitch area was completely 'corrected' back to normal-looking flux, and for a similar duration of 5.04 hours too. So not sure what is missing here or was corrected, if anything. Maybe it is the primary of a BGEB even. As I mentioned my glitch area transit idea a longshot anyway. But all this still an interesting exercise. 😃

    Semi-Major Axis a (A.U.) = 0.356

    Stellar diameter ratio = 0.60

    Stellar mass ratio = 0.60

    Duration ~= 6.00 hours

    Period ~= 100.16 days

    Semi-Major Axis a (A.U.) = 0.335

    Stellar diameter ratio = 0.50

    Stellar mass ratio = 0.50

    Duration ~= 5.32 hours

    Period ~= 100.15 days

    Semi-Major Axis a (A.U.) = 0.235

    Stellar diameter ratio = 0.90

    Stellar mass ratio = 0.90

    Duration ~= 5.98 hours

    Period ~= 43.86 days

    T1
    T2
    T1a
    T2a
    T3a
    T4a

    SkyView(s) for EPIC 201205007:

    SV1
    SV2

    SkyView data:

    N | Cat | ID/Name | RA/Lon | Dec/Lat | X | Y

    1 | http://archive.stsci.edu/k2/epic/search.php? | 201205007 | 169.2672| -3.9857| 150.0| 150.0

    2 | http://archive.stsci.edu/k2/epic/search.php? | 201204931 | 169.2690| -3.9877| 142.2| 141.5

    3 | http://archive.stsci.edu/k2/epic/search.php? | 201205574 | 169.2819| -3.9732| 87.2| 203.4

    4 | http://archive.stsci.edu/k2/epic/search.php? | 201206102 | 169.2734| -3.9607| 123.6| 257.2

    5 | http://archive.stsci.edu/k2/epic/search.php? | 201205750 | 169.2966| -3.9691| 24.3| 221.1

    6 | http://archive.stsci.edu/k2/epic/search.php? | 201203850 | 169.2877| -4.0142| 62.3| 27.8

    7 | http://archive.stsci.edu/k2/epic/search.php? | 201204224 | 169.2977| -4.0053| 19.5| 65.7

    Posted

  • Dolorous_Edd by Dolorous_Edd

    Link to 2MASS catalog

    2MASS color - color

    H - K = 0.11

    J - H = 0.644

    J - K = 0.754

    Link to USNO B1 catalog

    Posted

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

    Thanks DE. What is your guess as to the size of this star? I tend to think Hans Martin's estimate is closer at 0.5x Sol than my 0.9x guess, but can't back that up with data just yet.

    Posted

  • zoo3hans by zoo3hans

    I'm no expert in this, but it could be a K7V or M0V red dward then. Expected radius about 0.6 R_sol.

    See for example http://www.pas.rochester.edu/~emamajek/spt/K7V.txt

    Posted

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

    Agree, looking 2MASS colors I lean towards M0 dwarf too

    Now, target listed under GO1059

    http://keplerscience.arc.nasa.gov/K2/docs/Campaigns/C1/GO1059_Stello.pdf

    further support this

    Posted

  • zoo3hans by zoo3hans

    QUALITY flag of the target_pixel_file:

    quality

    Posted