arXiv subjects

P. Sari

Publications and source records attributed to P. Sari.

21 records · Page 2Linked to original sources

arXiv2007

HAT-P-3b: A heavy-element rich planet transiting a K dwarf star

We report the discovery of a Jupiter-size planet transiting a relatively bright (V = 11.56) and metal-rich early K dwarf star with a period of about 2.9 days. On the basis of follow-up photometry and spectroscopy we determine the mass and radius of the planet, HAT-P-3b, to be M_p = 0.599 +/- 0.026 M_Jup and R_p = 0.890 +/- 0.046 R_Jup. The relatively small size of the object for its mass implies the presence of about 75 Earth masses worth of heavy elements (1/3 of the total mass) based on current theories of irradiated extrasolar giant planets, similar to the mass of the core inferred for the transiting planet HD 149026b. The bulk density of HAT-P-3b is found to be rho_p = 1.06 +/- 0.17 g/cm^3, and the planet orbits the star at a distance of 0.03894 AU. Ephemerides for the transit centers are T_c = 2,454,218.7594 +/- 0.0029 + N (2.899703 +/- 0.000054) (HJD).

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arXiv2007

HD147506b: A Super-Massive Planet in an Eccentric Orbit Transiting a Bright Star

We report the discovery of a massive (Mp = 9.04+/-0.50 MJup) planet transiting the bright (V = 8.7) F8 star HD 147506, with an orbital period of 5.63341+/-0.00013 days and an eccentricity of e = 0.520+/-0.010. From the transit light curve we determine that the radius of the planet is Rp = 0.982^{+0.038}_{0.105}RJup. HD 147506b (also coined HAT-P-2b) has a mass about 9 times the average mass of previously-known transiting exoplanets, and a density of rho = 11.9 g cm-3, greater than that of rocky planets like the Earth. Its mass and radius are marginally consistent with theories of structure of massive giant planets composed of pure H and He, and may require a large (~100 Earth mass) core to account for. The high eccentricity causes a 9-fold variation of insolation of the planet between peri- and apastron. Using follow-up photometry, we find that the center of transit is Tmid = 2,454,212.8559 +/- 0.0007 (HJD), and the transit duration is 0.177 +/-0.002 d.

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arXiv2006

HAT-P-1b: A Large-Radius, Low-Density Exoplanet Transiting one Member of a Stellar Binary

Using small automated telescopes in Arizona and Hawaii, the HATNet project has detected an object transiting one member of the double star system ADS 16402 AB. This system is a pair of G0 main-sequence stars with age about 3 Gyr at a distance of ~139 pc and projected separation of ~1550 AU. The transit signal has a period of 4.46529 days and depth of 0.015 mag. From follow-up photometry and spectroscopy, we find that the object is a "hot Jupiter" planet with mass about 0.53 M_jup and radius ~1.36 R_jup traveling in an orbit with semimajor axis 0.055 AU and inclination about 85.9 deg, thus transiting the star at impact parameter 0.74 of the stellar radius. Based on a data set spanning three years, ephemerides for the transit center are: T_C = 2453984.397 + N_tr * 4.46529. The planet, designated HAT-P-1b, appears to be at least as large in radius, and smaller in mean density, than any previously-known planet.

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