Institute of Astronomy

Investigating Short-Period Planets around A Stars

SpeakerTalk DateTalk Series
Marshall Johnson29 July 2014Across HR 2014 Talks


Planet searches (except for direct imaging programs) have traditionally avoided main sequence A stars as these stars are not amenable to precise radial velocity measurements due to their wide, rotationally broadened stellar lines. Some A stars were observed by Kepler, providing the first opportunity to investigate the short-period planetary population of these stars. We are pursuing a program to validate Kepler planet candidates around rapidly rotating A stars using Doppler tomography, where we spectroscopically resolve the distortion in the stellar line profile during transit due to the Rossiter-McLaughlin effect. This also allows us to measure the spin-orbit misalignments of these planets. We present results from this program, as well as an estimate of the planet occurrence rate for short-period planets around main sequence A stars.