DISCOVERY OF A TRANSITING PLANET AND EIGHT ECLIPSING BINARIES IN HATNet FIELD G205

We report the discovery of HAT-P-8b, a transiting planet with mass M p = 1.52+0.18 –0.16 M J, radius R p = 1.50+0.08 –0.06 R J, and photometric period P = 3.076 days. HAT-P-8b has a somewhat inflated radius for its mass, and a somewhat large mass for its period. The host star is a solar-metallicity F dwarf, with mass M = 1.28 ± 0.04 M ☉ and R = 1.58+0.08 –0.06 R ☉. HAT-P-8b was initially identified as one of the 32 transiting-planet candidates in HATNet field G205. We describe the procedures that we have used to follow up these candidates with spectroscopic and photometric observations, and we present a status report on our interpretation for 28 of the candidates. Eight are eclipsing binaries with orbital solutions whose periods are consistent with their photometric ephemerides; two of these spectroscopic orbits are single-lined and six are double-lined.

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