Planet Hunters Talk

EPIC 204266965 .Red Giant type RR Lyrae variable stars or Cephed?

  • ACS_LPSP by ACS_LPSP

    This star shows the light curve, similar to the type RR Lyrae stars and Cepheids, but possible spectral class, based on the (H-K) mag = 0.690 and it shot it likely refers to a red giant that does not match the data belonging to a class of variable stars. Question: what class then include this variable star?
    Just EPIC 204266965 (he also USNOA2 0600-19972205)

    http://server3.sky-map.org/starview?object_type=1&object_id=623951981

    Based on adjusted data

    https://www.cfa.harvard.edu/~avanderb/k2c2/ep204266965.html

    It shows the kind of change the light curve of the star on the ID 2122 and ID 2134 . Most likely assume on the basis of previous study researches the star of these changes may be caused by the activity of the red giant but can not say exactly. I would like to ushlyshat any assumptions about these changes.

    Posted

  • davidbundy77 by davidbundy77

    It is listed on VSX

    ID V0891 Sco: https://www.aavso.org/vsx/index.php?view=detail.top&oid=33707

    Type is INS which according to GCVS variability types:

    "IN Orion variables. Irregular, eruptive variables connected with
    bright or dark diffuse nebulae or observed in the regions of these
    nebulae. Some of them may show cyclic light variations caused by
    axial rotation. In the Spectrum-Luminosity diagram, they are
    found in the area of the main sequence and subgiants. They are
    probably young objects that, during the course of further
    evolution, will become light-constant stars on the zero-age main
    sequence (ZAMS). The range of brightness variations may reach
    several magnitudes. In the case of rapid light variations having
    been observed (up to 1 mag in 1-10 days), the letter "S" is added
    to the symbol for the type (INS). "

    Posted

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

    Listed under

    GO2049 Prsa K2 campaigns 2 and 3 target proposal: Eclipsing Binary Star

    GO2054 Sanchis-Ojeda Using K2 to understand the rocky-gaseous transition

    IN Orion variables. Irregular, eruptive variables

    For irregular looks way too regular )

    Note: Raw LC was used

    enter image description here

    LC overview, is that a Blazhko modulation?

    enter image description here

    Posted

  • Dolorous_Edd by Dolorous_Edd

    In the UKIRT K-band and CFHT images there is a close companion to the north

    Blend?

    enter image description here

    CFHT G-band image (greyscale)

    enter image description here

    EPIC 204266965 is UGCS J161345.87-230029.3

    The companion is UGCS J161345.86-230026.7

    Posted

  • Dolorous_Edd by Dolorous_Edd

    Pulse profile

    enter image description here

    Posted

  • PlanetGazer8359 by PlanetGazer8359

    Wow

    Posted

  • davidbundy77 by davidbundy77 in response to Dolorous Edd's comment.

    The spectral data from UKIDSS which you linked shows much less redness than the Kepler data:

    EPIC 204266965 (H-K) mag = 11.986 - 11.890 = 0.096
    Companion (H-K) mag = 13.945 - 13.831 = 0.114

    This fits much better with the hypothesis that EPIC 204266965 is RR-Lyrae.

    Edit: In fact it looks like Planet Hunters has the wrong metadata

    Posted

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

    Thanks!

    There is only two references for the variability type, one from 1972 and another one from 1982
    so this is entirely possible that there could be misclassification. Phased curve shape is not the best I have ever seen, but this could be
    due to presence of the second star in aperture?

    Posted