title: 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 reflex motions of their host stars, and more recently through transits of some planets across the faces of the host stars. The detection of planets with the shortest known periods, 1.2-2.5 days, has mainly resulted from transit surveys which have generally targeted stars more massive than 0.75 M(o), where M(o) is the mass of the 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 masses in the range 0.44-0.75 M(o). 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, which occur only around stars of less than 0.88 M(o). This indicates that those orbiting very close to more-luminous stars might be evaporatively destroyed or that jovian planets around stars of lower mass might migrate to smaller radii.
authors.affiliation: Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, Maryland 21218, USA. ksahu@stsci.edu
authors.forename: Kailash C
authors.initials: KC
authors.lastname: Sahu
authors.forename: Stefano
authors.initials: S
authors.lastname: Casertano
authors.forename: Howard E
authors.initials: HE
authors.lastname: Bond
authors.forename: Jeff
authors.initials: J
authors.lastname: Valenti
authors.forename: T Ed
authors.initials: TE
authors.lastname: Smith
authors.forename: Dante
authors.initials: D
authors.lastname: Minniti
authors.forename: Manuela
authors.initials: M
authors.lastname: Zoccali
authors.forename: Mario
authors.initials: M
authors.lastname: Livio
authors.forename: Nino
authors.initials: N
authors.lastname: Panagia
authors.forename: Nikolai
authors.initials: N
authors.lastname: Piskunov
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Brown
authors.forename: Timothy
authors.initials: T
authors.lastname: Brown
authors.forename: Alvio
authors.initials: A
authors.lastname: Renzini
authors.forename: R Michael
authors.initials: RM
authors.lastname: Rich
authors.forename: Will
authors.initials: W
authors.lastname: Clarkson
authors.forename: Stephen
authors.initials: S
authors.lastname: Lubow