WASP-39b: a highly inflated Saturn-mass planet orbiting a late G-type star
WASP-39b: a highly inflated Saturn-mass planet orbiting a late G-type star
复制标题
DOI：
10.1051/0004-6361/201116671
复制
发表时间：
2011-07-01
影响因子：
6.5
通讯作者：
Wheatley, P. J.
中科院分区：
文献类型：
--
作者：
Faedi, F.;Barros, S. C. C.;Wheatley, P. J.
WASP-39 b是一颗高度膨胀的凌日行星，它围绕一颗晚G型矮星星星公转，公转周期为4.055259 +/-0.00008 d，凌日历元T-0 = 2455342.9688 +/- 0.0002（HJD），持续时间为0.1168 +/- 0.0008 d。结合WASP测光、高精度跟踪凌日测光和视向速度的分析，得出行星的质量为M-pl = 0.28 +/- 0.03 M-J，半径为R-pl = 1.27 +/- 0.04 R-J，平均密度为0.14 +/- 0.02 rho（J）。恒星参数为质量M星= 0.93 +/- 0.03 M圆点，半径R星= 0.895 +/- 0.23 R圆点，年龄9（-4）（+3）Gyr。只有WASP-17 b和WASP-31 b的密度低于WASP-39 b，尽管它们的质量略大，辐射量也略高。根据我们的光谱分析，WASP-39的金属丰度为[Fe/H] = -0.12 +/- 0.1 dex，我们发现这颗行星的平衡温度为1116（-32）（+33）K。这两个值都加强了观测到的这些参数与已知的土星质量行星的行星半径之间的经验相关性。
We present the discovery of WASP-39b, a highly inflated transiting Saturn-mass planet orbiting a late G-type dwarf star with a period of 4.055259 +/- 0.000008 d, Transit Epoch T-0 = 2 455 342.9688 +/- 0.0002 (HJD), of duration 0.1168 +/- 0.0008 d. A combined analysis of the WASP photometry, high-precision follow-up transit photometry, and radial velocities yield a planetary mass of M-pl = 0.28 +/- 0.03 M-J and a radius of R-pl = 1.27 +/- 0.04 R-J, resulting in a mean density of 0.14 +/- 0.02 rho(J). The stellar parameters are mass M-star = 0.93 +/- 0.03 M-circle dot, radius R-star = 0.895 +/- 0.23 R-circle dot, and age 9(-4)(+3) Gyr. Only WASP-17b and WASP-31b have lower densities than WASP-39b, although they are slightly more massive and highly irradiated planets. From our spectral analysis, the metallicity of WASP-39 is measured to be [Fe/H] = -0.12 +/- 0.1 dex, and we find the planet to have an equilibrium temperature of 1116(-32)(+33) K. Both values strengthen the observed empirical correlation between these parameters and the planetary radius for the known transiting Saturn-mass planets.