A Survey of Transit Timing Variations of M Stars Among Kepler's Targets: Evidence for Possible New Companions

M. Oshagh, G. Boué, N. Haghighipour, M. Montalto, P. Figueira, N. C. Santos

Abstract.
As the least massive stars, M stars have the greatest reflex acceleration due to an orbiting planet. The transit depths and transit times of planets around M stars are large and well-matched to the temporal resolution of ground-based telescopes as well as that of Kepler. As a result, M stars have been of particular interest for searching for planets in both radial velocity and transit photometry surveys. In continuation of our project to search for planetary companions around M stars, we have monitored the light curves of over 100 M stars in Kepler’s publicly available data sets Q0 to Q2. We used four criteria, namely, the magnitude, proper motion, H-Ks and J-H colors, and identified around 100 M stars in these data sets. A study of the light curves of these stars shows evidence of possible transiting systems as well as transit timing variations. Using a model-independent method, we analyzed these TTVs and determined the possibility that they might be due to planetary companions. We have found that the observed TTV signals in some of these systems cannot be explained by a constant period. However, they can be explained assuming that companions, with masses in the planet-mass domain, may be present in the system. We present the results of our survey and discuss the possibility of the new planetary candidate(s).

Extreme Solar Systems II
Moran, Wyoming, U.S.A.
September 2011

Type: Poster