A5083971994- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Scientific Research and Discoveries
- Galaxies: Formation, Evolution, Phenomena
- Geomagnetism and Paleomagnetism Studies
- Geophysics and Gravity Measurements
- Inertial Sensor and Navigation
- Advanced Statistical Methods and Models
- High-pressure geophysics and materials
- Complex Systems and Time Series Analysis
- Remote Sensing in Agriculture
- Distributed and Parallel Computing Systems
- Earth Systems and Cosmic Evolution
- Cosmology and Gravitation Theories
- Spectroscopy and Chemometric Analyses
- Planetary Science and Exploration
- Target Tracking and Data Fusion in Sensor Networks
- Molecular spectroscopy and chirality
- Astrophysical Phenomena and Observations
- Diverse Scientific and Engineering Research
- Relativity and Gravitational Theory
University of Geneva
2020-2023
Fundación Ciencias Exactas y Naturales
2019-2021
University of Buenos Aires
2019-2021
Global Social Observatory
2021
Institute of Astronomy and Space Physics
2019
Astronomical Institute of the Slovak Academy of Sciences
1994
University of Vienna
1994
Astrometric discovery of sub-stellar mass companions orbiting stars is exceedingly hard due to the required sub-milliarcsecond precision, limiting application this technique only a few instruments on target-per-target basis as well global astrometry space missions Hipparcos and Gaia. The third Gaia data release includes first astrometric orbital solutions, whose sensitivity in terms estimated companion extends down into planetary-mass regime. We present contribution `exoplanet pipeline' DR3...
Abstract We present the confirmation of eccentric warm giant planet TOI-201 b, first identified as a candidate in Transiting Exoplanet Survey Satellite photometry (Sectors 1–8, 10–13, and 27–28) confirmed using ground-based from Next Generation Transit radial velocities FEROS, HARPS, CORALIE, Minerva -Australis. b orbits young ( <?CDATA ${0.87}_{-0.49}^{+0.46}\,\mathrm{Gyr}$?> ) bright V = 9.07 mag) F-type star with 52.9781 day period. The has mass ${0.42}_{-0.03}^{+0.05}\,{M}_{{\rm{J}}}$?>...
Eccentricity is a parameter of particular interest as it an informative indicator the past planetary systems. It however not always clear whether eccentricity fitted on radial velocity data real or if artefact inappropriate modelling. In this work, we address question in two steps: first assume that model used for inference correct and present interesting features classical estimators. Secondly, study estimates are to be trusted when contain incorrectly modelled signals, such missed...
The radial velocity method is a very productive technique used to detect and confirm extrasolar planets. most recent spectrographs, such as ESPRESSO or EXPRES, have the potential Earth-like planets around Sun-like stars. However, stellar activity can induce variations that dilute even mimic signature of planet. A widely recognized for disentangling these signals model time series, jointly with indicators, using Gaussian processes their derivatives. modeling prohibitive in terms computational...
Hot Jupiters generally do not have nearby planet companions, as they may cleared out other planets during their inward migration from more distant orbits. This gives evidence that hot often migrate via high-eccentricity due to dynamical interactions between rather than dynamically cool mechanisms through the protoplanetary disk. Here we further refine unique system of WASP-132 by characterizing mass recently validated 1.0-day period super-Earth WASP-132c (TOI-822.02), interior 7.1-day...
The old G3V star Kepler-10 is known to host two transiting planets, the ultra-short-period super-Earth Kepler-10,b (P=0.837 d; rp=1.47 and long-period sub-Neptune Kepler-10,c (P=45.294 rp=2.35 a non-transiting planet that causes variations in transit times. Measurements of mass literature have shown disagreement, depending on radial-velocity dataset and/or modeling technique used. Here we report analysis almost 300 high-precision radial velocities gathered with HARPS-N spectrograph at...
Context. It is common practice to claim the detection of a signal if, for certain statistical significance metric, exceeds threshold fixed in advance. In context exoplanet searches radial velocity data, most metrics are Bayes factor and false alarm probability (FAP). Both criteria have proved useful, but do not directly address whether an should be claimed. Furthermore, it unclear which taken how robust detections model misspecification. Aims. The aim present work define criterion that...
ABSTRACT We present a comprehensive analysis of 10 yr HARPS radial velocities (RVs) the K2V dwarf star HD 13808, which has previously been reported to host two unconfirmed planet candidates. use state-of-the-art nested sampling algorithm PolyChord compare wide variety stellar activity models, including simple models exploiting linear correlations between RVs and indicators, harmonic for signals, more sophisticated Gaussian process regression model. show that overly simplistic are not...
Periodic radial velocity variations in the nearby M-dwarf star Gl411 are reported, based on measurements with SOPHIE spectrograph. Current data do not allow us to distinguish between a 12.95-day period and its one-day alias at 1.08 days, but favour former slightly. The variation has an amplitude of 1.6 m/s, making this lowest-amplitude signal detected up now. We have performed detailed analysis significance origin, including extensive simulations both uncorrelated correlated noise,...
Searches for periodicity in time series are often done with models of periodic signals, whose statistical significance is assessed via false alarm probabilities or Bayes factors. However, a statistically significant model might not originate from strictly source. In astronomy particular, one expects transient signals that show certain amount before vanishing. This situation encountered instance the search planets radial velocity data. While planetary expected to have stable phase, amplitude...
Context. We present precise radial-velocity measurements of five solar-type stars observed with the HARPS Echelle spectrograph mounted on 3.6-m telescope in La Silla (ESO, Chile). With a time span more than 10 yr and fairly dense sampling, survey is sensitive to low mass planets down super-Earths orbital periods up 100 days. Aims. Our goal was search for planetary companions around HD 39194, 93385, 96700, 154088, 189567 use Bayesian model comparison make an informed choice number systems...
Context. The observed scarcity of brown dwarfs in close orbits (within 10 au) around solar-type stars has posed significant questions about the origins these substellar companions. These not only pertain to but also impact our broader understanding planetary formation processes. However, resolve mechanisms, accurate observational constraints are essential. Notably, most have been discovered by radial velocity surveys, this method introduces uncertainties due its inability determine orbital...
We report the discovery of a 1.32$^{+0.10}_{-0.10}$ $\mathrm{M_{\rm Jup}}$ planet orbiting on 75.12 day period around G3V $10.8^{+2.1}_{-3.6}$ Gyr old star TOI-5542 (TIC 466206508; TYC 9086-1210-1). The was first detected by Transiting Exoplanet Survey Satellite (TESS) as single transit event in TESS Sector 13. A second observed 376 days later 27. planetary nature object has been confirmed ground-based spectroscopic and radial velocity observations from CORALIE HARPS spectrographs. third...
Our aim is to detect and characterise long-period companions around main sequence stars (spectral types late F early M). We use the RV method search for exoplanets stars. The variations are measured with HARPS at ESO 3.6 metre telescope. true mass inclination of our heavier provided by astrometry, which we proper motions from Hipparcos Gaia. Five Jupiter-mass reported orbit HIP54597, BD-210397 (x2), HD74698, HD94771 8.9 yr, 5.2 17.4 9.4 5.9 yr orbits, have minimum masses $2.01 \pm 0.03$,...
Context. The census of planets around M dwarfs in the solar neighbourhood meets two challenges: detecting best targets for future characterisation with ELTs, and studying statistics planet occurrence that are crucial to formation scenarios. radial velocity (RV) method remains most appropriate such a as it is sensitive widest ranges masses periods. HARPS, mounted on 3.6 m telescope at La Silla Observatory (ESO, Chile), has been obtaining measurements since 2003, can therefore be used analyse...
Hot Jupiters generally do not have nearby planet companions, as they may cleared out other planets during their inward migration from more distant orbits. This gives evidence that hot often migrate via high-eccentricity due to dynamical interactions between rather than dynamically cool mechanisms through the protoplanetary disk. Here we further refine unique system of WASP-132 by characterizing mass recently validated 1.0-day period super-Earth WASP-132c (TOI-822.02) interior 7.1-day Jupiter...
Context. The observed scarcity of brown dwarfs in close orbits (within 10 au) around solar-type stars poses significant questions about the origins these substellar companions. These impact our broader understanding planetary formation processes. However, to resolve mechanisms, accurate observational constraints are essential. Most have been discovered by radial velocity surveys, but this method introduces uncertainties due its inability determine orbital inclination, leaving true mass-and...
We report the discovery of a 1.32$^{+0.10}_{-0.10}$ $\mathrm{M_{\rm Jup}}$ planet orbiting on 75.12 day period around G3V $10.8^{+2.1}_{-3.6}$ Gyr old star TOI-5542 (TIC 466206508; TYC 9086-1210-1). The was first detected by Transiting Exoplanet Survey Satellite (TESS) as single transit event in TESS Sector 13. A second observed 376 days later 27. planetary nature object has been confirmed ground-based spectroscopic and radial velocity observations from CORALIE HARPS spectrographs. third...