HAT-P-25b: a Hot-Jupiter Transiting a Moderately Faint G Star

Abstract

We report the discovery of HAT-P-25b, a transiting extrasolar planet orbiting the V = 13.19 G5 dwarf star GSC 1788-01237, with a period P = 3.652836 +/- 0.000019 days, transit epoch Tc = 2455176.85173 +/- 0.00047 (BJD), and transit duration 0.1174 +/- 0.0017 days. The host star has mass of 1.01 +/- 0.03 M(Sun), radius of 0.96 +(0.05)-(0.04) R(Sun), effective temperature 5500 +/- 80 K, and metallicity [Fe/H] = +0.31 +/- 0.08. The planetary companion has a mass of 0.567 +/- 0.022 M(Jup), and radius of 1.190 +(0.081)-(0.056) R(Jup) yielding a mean density of 0.42 +/- 0.07 g cm-3. Comparing these observations with recent theoretical models, we find that HAT-P-25b is consistent with a hydrogen-helium dominated gas giant planet with negligible core mass and age 3.2 +/- 2.3 Gyr. The properties of HAT-P-25b support several previously observed correlations for planets in the mass range 0.4 < M < 0.7 M(Jup), including those of core mass vs. metallicity, planet radius vs. equilibrium temperature, and orbital period vs. planet mass. We also note that HAT-P-25b orbits the faintest star found by HATNet to have a transiting planet to date, and is one of only a very few number of planets discovered from the ground orbiting a star fainter than V = 13.0.

11 pages, 8 figures, 5 tables, submitted to ApJ

References in corpus (17)

• Improving Stellar and Planetary Parameters of Transiting Planet Systems: The Case of TrES-2
• Homogeneous studies of transiting extrasolar planets. III. Additional planets and stellar models
• HAT-P-1b: A Large-Radius, Low-Density Exoplanet Transiting one Member of a Stellar Binary
• HAT-P-7b: An Extremely Hot Massive Planet Transiting a Bright Star in the Kepler Field
• Transiting exoplanets from the CoRoT space mission I - CoRoT-Exo-1b: a low-density short-period planet around a G0V star
• HD147506b: A Super-Massive Planet in an Eccentric Orbit Transiting a Bright Star
• TASS Mark IV Photometric Survey of the Northern Sky
• HAT-P-12b: A Low-Density Sub-Saturn Mass Planet Transiting a Metal-Poor K Dwarf
• HAT-P-3b: A heavy-element rich planet transiting a K dwarf star
• HAT-P-18b and HAT-P-19b: Two Low-Density Saturn-Mass Planets Transiting Metal-Rich K Stars
• Astrometry in Wide-field Surveys
• HAT-P-15b: A 10.9-day Extrasolar Planet Transiting a Solar-type Star
• HAT-P-28b and HAT-P-29b: Two Sub-Jupiter Mass Transiting Planets
• WASP-34b: a near-grazing transiting sub-Jupiter-mass exoplanet in a hierarchical triple system
• WASP-25b: a 0.6 M_J planet in the Southern hemisphere
• TrES-5: A Massive Jupiter-sized Planet Transiting A Cool G-dwarf
• Tools for discovering and characterizing extrasolar planets

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