HAT-P-42b and HAT-P-43b. Two inflated transiting hot Jupiters from the HATNet Survey

October 2013 • 2013A&A...558A..86B

Authors • Boisse, I. • Hartman, J. D. • Bakos, G. Á. • Penev, K. • Csubry, Z. • Béky, B. • Latham, D. W. • Bieryla, A. • Torres, G. • Kovács, G. • Buchhave, L. A. • Hansen, T. • Everett, M. • Esquerdo, G. A. • Szklenár, T. • Falco, E. • Shporer, A. • Fulton, B. J. • Noyes, R. W. • Stefanik, R. P. • Lázár, J. • Papp, I. • Sári, P.

Aims: We announce the discovery of two new transiting planets, and provide their accurate initial characterization.
Methods: First identified from the HATNet wide-field photometric survey, these candidate transiting planets were then followed-up with a variety of photometric observations. Determining the planetary nature of the objects and characterizing the parameters of the systems were mainly done with the SOPHIE spectrograph at the 1.93 m telescope at OHP and the TRES spectrograph at the 1.5 m telescope at FLWO.
Results: HAT-P-42b and HAT-P-43b are typical hot Jupiters on circular orbits around early-G/late-F main sequence host stars, with periods of 4.641878 ± 0.000032 and 3.332687 ± 0.000015 days, masses of 1.044 ± 0.083 and 0.662 ± 0.060 MJ, and radii of 1.280 ± 0.153 and 1.28+0.062-0.033RJ, respectively. These discoveries increase the sample of planets with measured mean densities, which are needed to constrain theories of planetary interiors and atmospheres. Moreover, their hosts are relatively bright (V < 13.5), which facilitates further follow-up studies.

Full Table 2 is only available in electronic form at the CDS via anonymous ftp to ( or via photometric/spectroscopic data presented in this paper are based in part on observations carried out by the Hungarian-made Automated Telescope Network, using telescopes operated at the Fred Lawrence Whipple Observatory (FLWO) of the Smithsonian Astrophysical Observatory (SAO), and at the Submillimeter Array (SMA) of SAO, by the Tillinghast Reflector 1.5 m telescope and the 1.2 m telescope, both operated by SAO at FLWO, by the SOPHIE spectrograph mounted on the 1.93 m telescope at Observatoire de Haute Provence, France (runs DDT-Dec. 2011), by the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias, and by the facilities of the Las Cumbres Observatory Global Telescope.


IPAC Authors


Benjamin Fulton

Assistant Scientist