Transiting extrasolar planetary candidates in the Galactic bulge
Abstract
More than 200 extrasolar planets have been discovered around relatively nearby stars, primarily through the Doppler line shifts owing to the reflex motions of their host stars, and more recently through transits of some planets across the face of the host stars. The detection of planets with the shortest known periods, 1.2 to 2.5 days, has mainly resulted from transit surveys which have generally targeted stars more massive than 0.75 M_sun. Here we report the results from a planetary transit search performed in a rich stellar field towards the Galactic bulge. We discovered 16 candidates with orbital periods between 0.4 and 4.2 days, five of which orbit stars of 0.44 to 0.75 M_sun. In two cases, radial-velocity measurements support the planetary nature of the companions. Five candidates have orbital periods below 1.0 day, constituting a new class of ultra-short-period planets (USPPs), which occur only around stars of less than 0.88 M_sun. This indicates that those orbiting very close to more luminous stars might be evaporatively destroyed, or that jovian planets around lower-mass stars might migrate to smaller radii.
Cite
@article{arxiv.astro-ph/0610098,
title = {Transiting extrasolar planetary candidates in the Galactic bulge},
author = {Kailash C. Sahu and Stefano Casertano and Howard E. Bond and Jeff Valenti and T. Ed Smith and Dante Minniti and Manuela Zoccali and Mario Livio and Nino Panagia and Nikolai Piskunov and Thomas M. Brown and Timothy Brown and Alvio Renzini and R. Michael Rich and Will Clarkson and Stephen Lubow},
journal= {arXiv preprint arXiv:astro-ph/0610098},
year = {2009}
}
Comments
To appear in October 5, 2006 issue of Nature