Exoplanetary systems: past, present, and future
High-resolution Imaging of Transiting Extrasolar Planetary systems (HITEP)
Daniel Evans
John Southworth (Keele)
Keele University
We present the initial results of an ongoing search for close stellar companions to 101 transiting exoplanet systems in the Southern hemisphere. The presence, or lack of, distant stellar companions is a key discriminator between several competing theories for hot Jupiter formation, whilst both physically associated and background stars are important sources of contaminating light. This is the first survey to concentrate on targets in the South, performed using the Lucky Imager on the Danish 1.54m telescope at La Silla, which is capable of simultaneous observations in two colours. We provide the first astrometric and photometric measurements of 28 candidate companions located within 5 arcseconds of a host star, as well as follow up observations of 23 previously identified companions. For a subset of targets, we are able to analyse whether the candidate companions show common proper motion with the planet host star, or to compare the distances to the two stars based on two colour photometry. We have also investigated how the measured fraction of wide binaries among solar type stars compares to our sample of detected companions around TEP host stars, finding that the two may not be as different as has previously been claimed.


09:00 - 10:30