SOPHIE velocimetry of Kepler transit candidates XVII. The physical properties of giant exoplanets within 400 days of period

By A. Santerne, C. Moutou, M. Tsantaki, F. Bouchy, G. Hébrard, V. Adibekyan, J. Almenara, L. Amard, S. Barros, I. Boisse and 12 more. 2015

212 citations recorded by the source corpus.

While giant extrasolar planets have been studied for more than two decades now, there are still some open questions such as their dominant formation and migration process, as well as their atmospheric evolution in different stellar environments. In this paper, we study a sample of giant transiting exoplanets detected by the Kepler telescope with orbital periods up to 400 days. We first defined a sample of 129 giant-planet candidates that we followed up with the SOPHIE spectrograph (OHP, France) in a 6-year radial velocity campaign. This allow us to unveil the nature of these candidates and to measure a false-positive rate of 54.6 +/- 6.5 % for giant-planet candidates orbiting within 400 days of period. Based on a sample of confirmed or likely planets, we then derive the occurrence rates of giant planets in different ranges of orbital periods. The overall occurrence rate of giant planets within 400 days is 4.6 +/- 0.6 %. We recover, for the first time in the Kepler data, the different populations of giant planets reported by radial velocity surveys. Comparing these rates with other yields, we find that the occurrence rate of giant planets is lower only for hot jupiters but not for the longer period planets. We also derive a first measurement on the occurrence rate of brown dwarfs in the brown-dwarf desert with a value of 0.29 +/- 0.17 %. Finally, we discuss the physical properties of the giant planets in our sample. We confirm that giant planets receiving a moderate irradiation are not inflated but we find that they are in average smaller than predicted by formation and evolution models. In this regime of low-irradiated giant planets, we find a possible correlation between their bulk density and the Iron abundance of the host star, which needs more detections to be confirmed.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/9cee1771f7f1173002c39857a9b84b81d3ed5933

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. D. Huber
2. E. Gaidos
3. J. V. van Saders
4. G. Mulders
5. Ilaria Pascucci
6. T. Berger
7. C. Dressing
8. F. Ciesla

In Instrumentation

1. E. Gaidos
2. D. Huber
3. J. V. van Saders
4. T. Berger
5. D. Apai
6. Ilaria Pascucci
7. G. Mulders
8. C. Mordasini

Citations in the corpus

• Hints for a Turnover at the Snow Line in the Giant Planet Occurrence Rate (2018, background): “GPs show a rising occurrence rate out to the ∼1 au semi-major axis covered by Kepler (Dong & Zhu 2013; Santerne et al. 2016).”
• Revised Radii of Kepler Stars and Planets Using Gaia Data Release 2 (2018, methodology): “Despite the disposition listed in DR25, Kepler - 470b was identified by Santerne et al. (2016) to be an eclipsing binary based on radial velocities.”
• The Exoplanet Population Observation Simulator. I. The Inner Edges of Planetary Systems (2018, background): “…planet size of 6 R⊕ is chosen to exclude giant planets, which have a different distribution of orbital periods than sub-Neptunes (Dong & Zhu 2013; Santerne et al. 2016), are less often part of multiplanet systems (Steffen et al. 2012), or have dissimilar sizes than other planets in the system…”
• THE KEPLER FOLLOW-UP OBSERVATION PROGRAM. I. A CATALOG OF COMPANIONS TO KEPLER STARS FROM HIGH-RESOLUTION IMAGING (2016, background): “…Mullally et al. 2015; Desert et al. 2015; McCauliff et al. 2015; Santerne et al. 2016; Morton et al. 2016), with current estimates for false positive rates ranging from ∼ 10% for small planets (Fressin et al. 2013) to as high as 55% for giant planets (Santerne et al. 2016; Morton et al. 2016).”