Related papers: About putative Neptune-like extrasolar planetary c…

Transit surveys indicate that there is a deficit of Neptune-sized planets on close-in orbits. If this ``Neptune desert' is entirely cleared out by atmospheric mass loss, then planets at its upper edge should only be marginally stable…

We present the discovery and characterization of a new transiting planet from Campaign 17 of the Kepler extended mission K2. HD 119130 b is a warm sub-Neptune on a 17-d orbit around a bright (V = 9.9 mag) solar-like G3 V star with a mass…

We present here the detection of a brown dwarf orbiting the A9V star HD180777. The radial velocity measurements, obtained with the ELODIE echelle spectrograph at the Haute-Provence Observatory, show a main variation with a period of 28.4…

Beyond orbital periods of 10 days, there is a dearth of known transiting gas giants. On longer orbits, planets are less affected by their host star, and become ideal probes of planet formation, migration and evolution. We report the…

We have computed evolutionary models for extrasolar planets which range in mass from 0.1 to 3.0 Jovian Masses, and which range in equilibrium temperature from 113 K to 2000 K. We present four sequences of models, designed to show the…

We present an independent Doppler validation and dynamical orbital analysis of the two-planet system HD 107148, which was recently announced in Rosenthal et al. (2021). Our detailed analyses are based on literature HIRES data and newly…

Context. Due to their low transit probability, the long-period planets are, as a population, only partially probed by transit surveys. Radial velocity surveys thus have a key role to play, in particular for giant planets. Cold Jupiters…

In 2016, Kepler/K2 detected a system of two sub-Neptunes transiting the star HD 224018, one of them showing a mono-transit event. In 2017, we began a spectroscopic follow-up with HARPS-N to measure the dynamical masses of the planets using…

Population studies of Kepler's multi-planet systems have revealed a surprising degree of structure in their underlying architectures. Information from a detected transiting planet can be combined with a population model to make predictions…

We conducted a Doppler survey at Keck combined with NIRC2 K-band AO imaging to search for massive, long-period companions to 123 known exoplanet systems with one or two planets detected using the radial velocity (RV) method. Our survey is…

Much remains to be understood about the nature of exoplanets smaller than Neptune, most of which have been discovered in compact multi-planet systems. With its inner ultra-short period planet b aligned with the star and two larger outer…

We announce the detection of two new planetary-mass companions around Kepler-451 binary system in addition to the one detected previously based on eclipse timing variation analysis. We found that an inner planet with 43 d period with a…

Directly imaging temperate rocky planets orbiting nearby, Sun-like stars with a 6-m-class IR/O/UV space telescope, recently dubbed the Habitable Worlds Observatory, is a high priority goal of the Astro2020 Decadal Survey. To prepare for…

Hot super-Earths are exoplanets with masses < 10 Earth masses and orbital periods < 20 days. Around 8 hot super-Earths have been discovered in the neighborhood of solar system. In this lecture, we review the mechanisms for the formation of…

We analyze data from the Quarter 1-17 Data Release 24 (Q1--Q17 DR24) planet candidate catalog from NASA's Kepler mission, specifically comparing systems with single transiting planets to systems with multiple transiting planets, and…

Precise radial-velocity observations at Haute-Provence Observatory (OHP, France) with the ELODIE echelle spectrograph have been undertaken since 1994. In addition to several discoveries described elsewhere, including and following that of…

11 UMi and HD 32518 belong to a sample of 62 K giant stars that has been observed since February 2004 using the 2m Alfred Jensch telescope of the Th\"uringer Landessternwarte (TLS) to measure precise radial velocities (RVs). The aim of this…

Numerical simulations suggest that Neptune primordial co-orbitals may outnumber the equivalent population hosted by Jupiter, yet the objects remain elusive. Since the first discovery in 2001 just 10 minor planets have been identified as…

Earth-sized planets in the habitable zones of M dwarfs are good candidates for the study of habitability and detection of biosignatures. To search for these planets, we analyze all available radial velocity data and apply four signal…

We employ a two-dimensional grid-based hydrodynamic model to simulate upper atmospheric dynamics on extrasolar giant planets. Our model is well-suited to simulate the dynamics of the atmospheres of planets with high orbital eccentricity…