HAT-P-32b and HAT-P-33b: Two highly inflated hot Jupiters transiting high-jitter stars

J. D. Hartman, G. Á Bakos, G. Torres, D. W. Latham, Géza Kovács, B. Béky, S. N. Quinn, T. Mazeh, A. Shporer, G. W. Marcy, A. W. Howard, D. A. Fischer, J. A. Johnson, G. A. Esquerdo, R. W. Noyes, D. D. Sasselov, R. P. Stefanik, J. M. Fernandez, T. Szklenár, J. LázárI. Papp, P. Sári

Research output: Contribution to journalArticle

81 Citations (Scopus)

Abstract

We report the discovery of two exoplanets transiting high-jitter stars. HAT-P-32b orbits the bright V = 11.289 late-F-early-G dwarf star GSC 3281-00800, with a period P = 2.150008 ± 0.000001d. The stellar and planetary masses and radii depend on the eccentricity of the system, which is poorly constrained due to the high-velocity jitter (∼80 m s-1). Assuming a circular orbit, the star has a mass of 1.16±0.04 M Ȯ and radius of 1.22±0.02 R Ȯ, while the planet has a mass of 0.860±0.164 M J and a radius of 1.789 0.025R J. The second planet, HAT-P-33b, orbits the bright V = 11.188 late-F dwarf star GSC 2461-00988, with a period P = 3.474474±0.000001d. As for HAT-P-32, the stellar and planetary masses and radii of HAT-P-33 depend on the eccentricity, which is poorly constrained due to the high jitter (∼50 m s-1). In this case, spectral line bisector spans (BSs) are significantly anti-correlated with the radial velocity residuals, and we are able to use this correlation to reduce the residual rms to ∼35 m s-1. We find that the star has a mass of 1.38±0.04 M Ȯ and a radius of 1.64±0.03 R Ȯ while the planet has a mass of 0.762 0.101 M J and a radius of 1.686±0.045R J for an assumed circular orbit. Due to the large BS variations exhibited by both stars we rely on detailed modeling of the photometric light curves to rule out blend scenarios. Both planets are among the largest radii transiting planets discovered to date.

Original languageEnglish
Article number59
JournalAstrophysical Journal
Volume742
Issue number1
DOIs
Publication statusPublished - Nov 20 2011

    Fingerprint

Keywords

  • planetary systems
  • stars: individual (HAT-P-32, GSC 3281-00800, HAT-P-33, GSC 2461-00988)
  • techniques: photometric
  • techniques: spectroscopic

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Hartman, J. D., Bakos, G. Á., Torres, G., Latham, D. W., Kovács, G., Béky, B., Quinn, S. N., Mazeh, T., Shporer, A., Marcy, G. W., Howard, A. W., Fischer, D. A., Johnson, J. A., Esquerdo, G. A., Noyes, R. W., Sasselov, D. D., Stefanik, R. P., Fernandez, J. M., Szklenár, T., ... Sári, P. (2011). HAT-P-32b and HAT-P-33b: Two highly inflated hot Jupiters transiting high-jitter stars. Astrophysical Journal, 742(1), [59]. https://doi.org/10.1088/0004-637X/742/1/59