TrES-3: A Nearby, Massive, Transiting Hot Jupiter in a 31-Hour Orbit

TL;DR

TrES-3 is a newly discovered, massive hot Jupiter with an extremely short 31-hour orbit, offering unique opportunities for studying orbital decay, evaporation, and atmospheric properties.

Contribution

This paper reports the discovery and characterization of TrES-3, a massive transiting hot Jupiter with one of the shortest known orbital periods, including detailed stellar and planetary parameters.

Findings

Planetary mass: 1.92 ± 0.23 M_Jup

Orbital period: 1.30619 days

Suitable for atmospheric and orbital decay studies

Abstract

We describe the discovery of a massive transiting hot Jupiter with a very short orbital period (1.30619 d), which we name TrES-3. From spectroscopy of the host star GSC 03089-00929, we measure T_eff = 5720 +- 150 K, logg=4.6 +- 0.3, and vsini < 2 km/s, and derive a stellar mass of 0.90 +- 0.15 M_sun. We estimate a planetary mass of 1.92 +- 0.23 M_Jup, based on the sinusoidal variation of our high-precision radial velocity measurements. This variation has a period and phase consistent with our transit photometry. Our spectra show no evidence of line bisector variations that would indicate a blended eclipsing binary star. From detailed modeling of our B and z photometry of the 2.5%-deep transits, we determine a stellar radius 0.802 +- 0.046 R_sun and a planetary radius 1.295 +- 0.081 R_Jup. TrES-3 has one of the shortest orbital periods of the known transiting exoplanets, facilitating studies of orbital decay and mass loss due to evaporation, and making it an excellent target for future studies of infrared emission and reflected starlight.