A5006049715- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Planetary Science and Exploration
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Scientific Research and Discoveries
- Solar and Space Plasma Dynamics
- Spacecraft and Cryogenic Technologies
- Space Exploration and Technology
- Geophysics and Gravity Measurements
- High-pressure geophysics and materials
- Molecular Spectroscopy and Structure
- Atmospheric Ozone and Climate
- Adaptive optics and wavefront sensing
- Isotope Analysis in Ecology
- Spacecraft Design and Technology
- Astronomical and nuclear sciences
- Methane Hydrates and Related Phenomena
- Semiconductor Quantum Structures and Devices
- Space Science and Extraterrestrial Life
- Advanced Semiconductor Detectors and Materials
- SAS software applications and methods
- Spectroscopy and Laser Applications
University of Bern
2015-2024
International Space Science Institute
2014-2024
Observatoire des Sciences de l’Univers Terre Homme Environnement Temps Astronomie
2006-2023
University of Padua
2023
Max Planck Institute for Astronomy
2018
Max Planck Society
2018
University of Geneva
2017
Imperial College London
2017
ETH Zurich
2017
Australian National University
2003-2016
We present a new model of giant planet formation that extends the core-accretion Pollack etal (1996) to include migration, disc evolution and gap formation. show taking into account these effects can lead much more rapid planets, making it compatible with typical lifetimes inferred from observations young circumstellar discs. This speed up is due fact migration prevents severe depletion feeding zone as observed in situ calculations. Hence, growing never isolated reach cross-over mass on...
With the high number of extrasolar planets discovered by now, it becomes possible to constrain theoretical formation models in a statistical sense. This paper is first series which we carry out large planet population synthesis calculations. We begin with mainly dedicated presentation our approach, but also discussion representative synthetic planetary solar like stars. Based as tightly on observational data, have derived probability distributions for most important initial conditions...
ESPRESSO is the new high-resolution spectrograph of ESO's Very-Large Telescope (VLT). It was designed for ultra-high radial-velocity precision and extreme spectral fidelity with aim performing exoplanet research fundamental astrophysical experiments unprecedented accuracy. able to observe any four Unit Telescopes (UT) VLT at a resolving power 140,000 or 190,000 over 378.2 788.7 nm wavelength range, all UTs together, turning into 16-m diameter equivalent telescope in terms collecting area,...
Context. This is the fourth paper in a series showing results of planet population synthesis calculations. Aims. Our goal this to systematically study effects important disk properties, namely metallicity, mass and lifetime on fundamental planetary properties. Methods. For large number protoplanetary disks we calculate planets with our core accretion formation model including migration evolution. Results. We find correlations: Regarding initial function, have different roles: high [Fe/H],...
We present an inversion method based on Bayesian analysis to constrain the interior structure of terrestrial exoplanets, in form chemical composition mantle and core size. Specifically, we identify what parts exoplanets can be determined from observations mass, radius, stellar elemental abundances. perform a full probabilistic inverse formally account for observational model uncertainties obtain confidence regions models. This enables us characterize how variability depends data associated...
Planetesimal formation stage represents a major gap in our understanding of the planet process. The late-stage accretion models typically make arbitrary assumptions about planetesimals and pebbles distribution while dust evolution predict that planetesimal is only possible at some orbital distances. We want to test importance water snow line for triggering first during gas-rich phase protoplanetary disk, when cores giant planets have form. connect prescriptions gas disk evolution, growth...
This is the second paper in a series of papers showing results extrasolar planet population synthesis calculations. In companion (Paper I), we have presented detail our methods. By applying an observational detection bias for radial velocity surveys, identify potentially detectable synthetic planets. The properties these planets are compared quantitative statistical tests with carefully selected sub-population actual exoplanets. We use two dimensional Kolmogorov-Smirnov test to compare...
A first characterization of many exoplanets has recently been achieved by the observational determination their radius. For some planets, a measurement luminosity also possible, with more directly imaged planets expected in future. The statistical through mass-radius and mass-luminosity diagram is thus becoming possible. This for planet formation evolution theory similar importance as mass-distance diagram. Our aim this companion paper to extend our model into coupled model. We want...
Ground based radial velocity (RV) searches continue to discover exoplanets below Neptune mass down Earth mass. Furthermore, ground transit now reach milli-mag photometric precision and can size planets around bright stars. These will find stars anywhere on the sky, their discoveries representing prime science targets for further study due proximity brightness of host A mission follow-up measurements these is currently lacking. The first ESA S-class CHEOPS (CHaracterizing ExoPlanet Satellite)...
The consistency of planet formation models suffers from the disconnection between regime small and large bodies. This is primarily caused by so-called growth barriers: direct larger bodies halted at centimetre-sized objects particular conditions are required for larger, gravitationally bound planetesimals. We aim to connect dust evolution planetesimal identify regions protoplanetary discs that favourable kilometre-sized first planetary embryos. combine semi-analytical viscous disc evolution,...
The research of exoplanets has entered an era in which we characterize extrasolar planets. This become possible with measurements radii and luminosities. Meanwhile, radial velocity surveys discover also very low-mass Uniting all this observational data into one coherent picture to better understand planet formation is important, but difficult undertaking. Our approach develop a model can make testable predictions for these methods. We continue describe how have extended our self-consistently...
Determining the architecture of multi-planetary systems is one cornerstones understanding planet formation and evolution. Resonant are especially important as fragility their orbital configuration ensures that no significant scattering or collisional event has taken place since earliest phase when parent protoplanetary disc was still present. In this context, TOI-178 been subject particular attention first TESS observations hinted at a 2:3:3 resonant chain. Here we report results from...
Context. Previous theoretical works on planet formation around low-mass stars have often been limited to large planets and individual systems. As current surveys routinely detect down terrestrial size in these systems, models shifted toward a more holistic approach that reflects their diverse architectures. Aims. Here, we investigate identify differences the statistical distribution of modeled planets. We compare synthetic populations observed exoplanets discuss identified trends. Methods....
Aims. Comparing theoretical models with observations allows one to make key step forward towards an understanding of planetary systems. It however requires a model able (i) predict all the necessary observable quantities (not only masses and orbits, but also radii, luminosities, magnitudes, or evaporation rates) (ii) address large range in relevant (from Mars mass super-Jupiters) distances stellar-grazing wide orbits). Methods. We have developed combined global end-to-end formation evolution...
Proxima Centauri is the closest star to Sun. This small, low-mass, mid M dwarf known host an Earth-mass exoplanet with orbital period of 11.2 days within habitable zone, as well a long-period planet candidate close 5 years. We report on analysis large set observations taken ESPRESSO spectrograph at VLT aimed thorough evaluation presence third low-mass planetary companion, which started emerging during previous campaign. Radial velocities (RVs) were calculated using both cross-correlation...
We extend the core-accretion model of giant gaseous planets by Pollack et al. (\cite{P96}) to include migration, disc evolution and gap formation. Starting with a core fraction an Earth's mass located at 8 AU, we end our simulation onset runaway gas accretion when planet is 5.5 AU 1 Myr later. This timescale about factor ten shorter than one found even though was less massive initially viscously evolving. Other initial conditions can lead timescales. The reason for this speed-up result from...