A5070860031- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Solar and Space Plasma Dynamics
- Geophysics and Gravity Measurements
- Atmospheric Ozone and Climate
- Astrophysical Phenomena and Observations
- Spacecraft Design and Technology
- Space Exploration and Technology
- History and Developments in Astronomy
- Calibration and Measurement Techniques
- Spectroscopy and Laser Applications
- Adaptive optics and wavefront sensing
- Spacecraft and Cryogenic Technologies
- High-pressure geophysics and materials
- Astronomical and nuclear sciences
- Optical Polarization and Ellipsometry
- Planetary Science and Exploration
- Engineering and Test Systems
- Scientific Research and Discoveries
- Scientific Measurement and Uncertainty Evaluation
- Plasma Diagnostics and Applications
Centre National de la Recherche Scientifique
2013-2024
Aix-Marseille Université
2018-2024
Laboratoire d’Astrophysique de Marseille
2018-2024
Canadian Nautical Research Society
2024
Château Gombert
2023
Austrian Academy of Sciences
2023
University of Padua
2023
Space Research Institute
2023
University of Bern
2022
Institute of Astrophysics and Space Sciences
2022
We present photometric and spectroscopic observations of SN 2007if, an overluminous (MV = −20.4), red (B − V 0.16 at B-band maximum), slow-rising (trise 24 days) type Ia supernova (SN Ia) in a very faint (Mg −14.10) host galaxy. A spectrum 5 days past maximum light is direct match to the super-Chandrasekhar-mass candidate 2003fg, showing Si ii C ∼9000 km s−1. high signal-to-noise co-addition spectral time series reveals no Na i D absorption, suggesting negligible reddening galaxy, late-time...
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...
The CHaracterizing ExOPlanet Satellite (CHEOPS), to be launched in December 2019, will detect and characterize small size exoplanets via ultra high precision photometry during transits. CHEOPS is designed as a follow-up telescope therefore it monitor single target at time. scientific users retrieve science-ready light curves of the target, automatically generated by data reduction pipeline Science Operations Centre. This paper describes how processes series raw images and, particular,...
Aims. The catalog of Stars With ExoplanETs (SWEET-Cat) was originally introduced in 2013. Since then many more exoplanets have been confirmed, increasing significantly the number host stars listed there. A crucial step toward a comprehensive understanding these new worlds is precise and homogeneous characterization their stars. Better spectroscopic stellar parameters along with results from Gaia eDR3 provide updated for discovered planets. version catalog, whose homogeneity derivation key to...
CHEOPS(CHaracterising ExOPlanet Satellite) is an ESA S-class mission that observes bright stars at high cadence from low-Earth orbit. The main aim of the to characterize exoplanets transit nearby using ultrahigh precision photometry. Here we report analysis transits observed by CHEOPS during its Early Science observing programme for four well-known exoplanets: GJ436b, HD106315b, HD97658b and GJ1132b. done pycheops, open-source software package have developed easily efficiently analyse light...
Abstract We detect Ly α absorption from the escaping atmosphere of HD 63433c, a R = 2.67 ⊕ , P 20.5 day mini-Neptune orbiting young (440 Myr) solar analog in Ursa Major Moving Group. Using Hubble Space Telescope (HST)/Space Imaging Spectrograph, we measure transit depth 11.1 ± 1.5% blue wing and 8 3% red. This signal is unlikely to be due stellar variability, but should confirmed by an upcoming second observation with HST. do not inner planet, smaller 2.15 on 7.1 orbit. use Keck/NIRSPEC...
We report the discovery and characterisation of a pair sub-Neptunes transiting bright K-dwarf TOI-1064 (TIC 79748331), initially detected in TESS photometry. To characterise system, we performed retrieved CHEOPS, TESS, ground-based photometry, HARPS high-resolution spectroscopy, Gemini speckle imaging. host star determine $T_{\rm eff, \star}=4734\pm67$ K, $R_{\star}=0.726\pm0.007$ $R_{\odot}$, $M_{\star}=0.748\pm0.032$ $M_{\odot}$. present novel detrending method based on PSF shape-change...
Gas giants orbiting close to hot and massive early-type stars can reach dayside temperatures that are comparable those of the coldest stars. These "ultra-hot Jupiters" have atmospheres made ions atomic species from molecular dissociation feature strong day-to-night temperature gradients. Photometric observations at different orbital phases provide insights on planet atmospheric properties. We analyse photometric WASP-189 acquired with instrument CHEOPS derive constraints system architecture...
We present the discovery and characterisation of two transiting planets observed by \textit{TESS} in light curves young bright (V=9.67) star HD73583 (TOI-560). perform an intensive spectroscopic photometric space- ground-based follow-up order to confirm characterise system. found that is a ($\sim 500$~Myr) active with rotational period $12.08 \pm 0.11 $\,d, mass radius $ 0.73 0.02 M_\odot$ $0.65 R_\odot$, respectively. b ($P_b=6.3980420 _{ - 0.0000062 }^{+0.0000067}$ d) has $10.2...
We report nine new transit epochs of the extrasolar planet WASP-5b, observed in Bessell I band with Southern Astrophysical Research Telescope at Cerro Pachon Observatory and SMARTS 1 m Tololo Inter-American Observatory, between 2008 August 2009 October. The transits have been combined all previously published data for this to provide a Transit Timing Variation (TTV) analysis its orbit. find no evidence TTV rms variations larger than minute over 3 year time span. This result discards presence...
We present 15 new transit observations of the exoplanet WASP-43b in $i'$,$g'$, and $R$ filters with 1.0-m telescopes Las Cumbres Observatory Global Telescope (LCOGT) Network IAC80 telescope. combine our light curves 52 others from literature, to analyze homogeneously all available this exoplanet. By extending time span monitoring transits more than $5~yr$, by analyzing individual mid-times 72 transits, we study proposed shortening orbital period WASP-43b. estimate that times are well-matched...
The detection of a super-Earth and three mini-Neptunes transiting the bright ($V$ = 9.2 mag) star HD 108236 (also known as TOI-1233) was recently reported on basis TESS ground-based light curves. We perform first characterisation planetary system through high-precision CHEOPS photometry improve transit ephemerides parameters. characterise host spectroscopic analysis derive radius with infrared flux method. constrain stellar mass age by combining results obtained from two sets evolutionary...
AU Mic is a young planetary system with resolved debris disc showing signs of planet formation and two transiting warm Neptunes near mean-motion resonances. Here we analyse three transits b observed the CHaracterising ExOPlanet Satellite (CHEOPS), supplemented sector 1 27 Transiting Exoplanet Survey (TESS) photometry, All-Sky Automated (ASAS) from ground. The refined orbital period 8.462995 \pm 0.000003 d, whereas stellar rotational P_{rot}=4.8367 0.0006 d. periods indicate 7:4 spin--orbit...
55 Cnc e is a transiting super-Earth (radius $1.88\rm\,R_\oplus$ and mass $8\rm\, M_\oplus$) orbiting G8V host star on 17-hour orbit. Spitzer observations of the planet's phase curve at 4.5 $\mu$m revealed time-varying occultation depth, MOST optical are consistent with amplitude offset maximum light. Both broadband high-resolution spectroscopic analyses either high mean molecular weight atmosphere or no for planet e. A long term photometric monitoring campaign an independent telescope...
We report the detection of secondary eclipse hot Jupiter HD 209458 b in optical/visible light using CHEOPS space telescope. Our measurement 20.4 −3.3 +3.2 parts per million translates into a geometric albedo A g = 0.096 ± 0.016. The previously estimated dayside temperature about 1500 K implies that our consists predominantly reflected starlight and is largely uncontaminated by thermal emission. This makes present result one most robust measurements for any exoplanet. calculations...
Context: TOI-2076 is a transiting three-planet system of sub-Neptunes orbiting bright (G = 8.9 mag), young ($340\pm80$ Myr) K-type star. Although validated planetary system, the orbits two outer planets were unconstrained as only non-consecutive transits seen in TESS photometry. This left 11 and 7 possible period aliases for each. Aims: To reveal true these long-period planets, precise photometry targeted on highest-probability required. Long-term monitoring multi-planet systems can also...
We present a precise characterization of the TOI-561 planetary system obtained by combining previously published data with TESS and CHEOPS photometry, new set $62$ HARPS-N radial velocities (RVs). Our joint analysis confirms presence four transiting planets, namely b ($P = 0.45$ d, $R 1.42$ R$_\oplus$, $M 2.0$ M$_\oplus$), c 10.78$ 2.91$ 5.4$ d 25.7$ 2.82$ 13.2$ M$_\oplus$) e 77$ 2.55$ 12.6$ M$_\oplus$). Moreover, we identify an additional, long-period signal ($>450$ d) in RVs, which...
Context. Measurements of the occultation an exoplanet at visible wavelengths allow us to determine reflective properties a planetary atmosphere. The observed depth can be translated into geometric albedo. This in turn aids characterising structure and composition atmosphere by providing additional information on wavelength-dependent qualities aerosols Aims. Our aim is provide precise measurement albedo gas giant HD 189733b measuring broad optical bandpass CHEOPS (350–1100 nm). Methods. We...
ABSTRACT HIP 9618 (HD 12572, TOI-1471, TIC 306263608) is a bright (G = 9.0 mag) solar analogue. TESS photometry revealed the star to have two candidate planets with radii of 3.9 ± 0.044 R⊕ (HIP b) and 3.343 0.039 c). While 20.77291 d period b was measured unambiguously, c showed only transits separated by 680-d gap in time series, leaving many possibilities for period. To solve this issue, CHEOPS performed targeted aliases attempt recover true planet c, successfully determined be 52.56349 d....
Context. A large sample of long-period giant planets has been discovered thanks to long-term radial velocity surveys, but only a few dozen these have precise radius measurement. Transiting gas giants are crucial targets for the study atmospheric composition across wide range equilibrium temperatures and, more importantly, shedding light on formation and evolution planetary systems. Indeed, compared hot Jupiters, properties orbital parameters cooler unaltered by intense stellar irradiation...
Context . Since the discovery of first exoplanet almost three decades ago, number known exoplanets has increased dramatically. By beginning 2000s it was clear that dedicated facilities to advance our studies in this field were needed. The CHaracterising ExOPlanet Satellite (CHEOPS) is a space telescope specifically designed monitor transiting orbiting bright stars. In September 2023, CHEOPS completed its nominal mission duration 3.5 yr and remains excellent operational conditions. As...
We report the discovery of a brown dwarf on an eccentric orbit and with semimajor axis that places it in desert region around star HD191760. The has spectral type G3IV/V metallicity ([Fe/H]) 0.29 dex. HD191760 adds to small number metal-rich stars companions. (HD191760b) is found have orbital period 505.57+/-0.40 days 1.35+/-0.01 AU, placing firmly desert. eccentricity HD191760b be 0.63+/-0.01, meaning reaches as close 0.5 AU from host star. Dynamical simulations indicate no inner planets...