Masses, radii, and orbits of small Kepler planets: the transition from gaseous to rocky planets
Research output: Contribution to journal › Journal article › Research › peer-review
We report on the masses, sizes, and orbits of the planets orbiting 22 Kepler
stars. There are 49 planet candidates around these stars, including 42
detected through transits and 7 revealed by precise Doppler measurements
of the host stars. Based on an analysis of the Kepler brightness
measurements, along with high-resolution imaging and spectroscopy,
Doppler spectroscopy, and (for 11 stars) asteroseismology, we establish
low false-positive probabilities (FPPs) for all of the transiting
planets (41 of 42 have an FPP under 1%), and we constrain their sizes
and masses. Most of the transiting planets are smaller than three times
the size of Earth. For 16 planets, the Doppler signal was securely
detected, providing a direct measurement of the planet's mass. For the
other 26 planets we provide either marginal mass measurements or upper
limits to their masses and densities; in many cases we can rule out a
rocky composition. We identify six planets with densities above 5 g cm–3,
suggesting a mostly rocky interior for them. Indeed, the only planets
that are compatible with a purely rocky composition are smaller than ~2 R ⊕. Larger planets evidently contain a larger fraction of low-density material (H, He, and H2O).
Original language | English |
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Article number | 20 |
Journal | Astrophysical Journal Supplement Series |
Volume | 210 |
Issue number | 2 |
Number of pages | 70 |
ISSN | 0067-0049 |
DOIs | |
Publication status | Published - 1 Feb 2014 |
ID: 140160962