English

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

Astrophysics 2008-11-26 v2

Abstract

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.

Keywords

Cite

@article{arxiv.0705.0126,
  title  = {HD147506b: A Super-Massive Planet in an Eccentric Orbit Transiting a Bright Star},
  author = {G. A. Bakos and G. Kovacs and G. Torres and D. A. Fischer and D. W. Latham and R. W. Noyes and D. D. Sasselov and T. Mazeh and A. Shporer and R. P. Butler and R. P. Stefanik and J. M. Fernandez and A. Sozzetti and A. Pal and J. Johnson and G. W. Marcy and J. Winn and B. Sipocz and J. Lazar and I. Papp and P. Sari},
  journal= {arXiv preprint arXiv:0705.0126},
  year   = {2008}
}

Comments

Revised version sent to ApJ