Search Publications

Characterization of the K2-38 planetary system. Unraveling one of the densest planets known to date
DOI: 10.1051/0004-6361/202038187 Bibcode: 2020A&A...641A..92T

Bouchy, F.; Rebolo, R.; Pallé, E. +90 more

Context. An accurate characterization of the known exoplanet population is key to understanding the origin and evolution of planetary systems. Determining true planetary masses through the radial velocity (RV) method is expected to experience a great improvement thanks to the availability of ultra-stable echelle spectrographs.
Aims: We took a…

2020 Astronomy and Astrophysics
Gaia 27
GOODS-ALMA: Using IRAC and VLA to probe fainter millimeter galaxies
DOI: 10.1051/0004-6361/202038310 Bibcode: 2020A&A...643A..53F

Magnelli, B.; Daddi, E.; Elbaz, D. +33 more

In this paper, we extend the source detection in the GOODS-ALMA field (69 arcmin2, 1σ ≃ 0.18 mJy beam-1) to deeper levels than presented in our previous work. Using positional information at 3.6 and 4.5 µm (from Spitzer-IRAC) as well as the Very Large Array (VLA) at 3 GHz, we explore the presence of galaxies detected at…

2020 Astronomy and Astrophysics
eHST 26
Impulsive coronal heating during the interaction of surface magnetic fields in the lower solar atmosphere
DOI: 10.1051/0004-6361/202039099 Bibcode: 2020A&A...644A.130C

Peter, H.; Chitta, L. P.; Solanki, S. K. +1 more

Coronal plasma in the cores of solar active regions is impulsively heated to more than 5 MK. The nature and location of the magnetic energy source responsible for such impulsive heating is poorly understood. Using observations of seven active regions from the Solar Dynamics Observatory, we found that a majority of coronal loops hosting hot plasma …

2020 Astronomy and Astrophysics
IRIS 26
The RAdial Velocity Experiment (RAVE): Parameterisation of RAVE spectra based on convolutional neural networks
DOI: 10.1051/0004-6361/202038271 Bibcode: 2020A&A...644A.168G

Guiglion, G.; Valentini, M.; Anders, F. +22 more

Context. Data-driven methods play an increasingly important role in the field of astrophysics. In the context of large spectroscopic surveys of stars, data-driven methods are key in deducing physical parameters for millions of spectra in a short time. Convolutional neural networks (CNNs) enable us to connect observables (e.g. spectra, stellar magn…

2020 Astronomy and Astrophysics
Gaia 26
The VMC survey. XXXVIII. Proper motion of the Magellanic Bridge
DOI: 10.1051/0004-6361/202037478 Bibcode: 2020A&A...641A.134S

de Grijs, Richard; Ripepi, Vincenzo; Petr-Gotzens, Monika G. +14 more

Context. The Magellanic Clouds are a nearby pair of interacting dwarf galaxies and satellites of the Milky Way. Studying their kinematic properties is essential to understanding their origin and dynamical evolution. They have prominent tidal features and the kinematics of these features can give hints about the formation of tidal dwarfs, galaxy me…

2020 Astronomy and Astrophysics
eHST 26
Effect of metallicity on the detectability of rotational periods in solar-like stars
DOI: 10.1051/0004-6361/201936608 Bibcode: 2020A&A...634L...9W

Solanki, S. K.; Shapiro, A. I.; Krivova, N. A. +2 more

The accurate determination of stellar rotation periods is important for estimating stellar ages and for understanding stellar activity and evolution. While rotation periods can be determined for about thirty thousand stars in the Kepler field, there are over one hundred thousand stars, especially with low photometric variability and irregular patt…

2020 Astronomy and Astrophysics
Gaia 26
Compressed magnetized shells of atomic gas and the formation of the Corona Australis molecular cloud
DOI: 10.1051/0004-6361/202039282 Bibcode: 2020A&A...644A...5B

André, Ph.; Arzoumanian, D.; Palmeirim, P. +4 more

We present the identification of the previously unnoticed physical association between the Corona Australis molecular cloud (CrA), traced by interstellar dust emission, and two shell-like structures observed with line emission of atomic hydrogen (HI) at 21 cm. Although the existence of the two shells had already been reported in the literature, th…

2020 Astronomy and Astrophysics
Gaia Herschel 26
Spectral and atmospheric characterisation of a new benchmark brown dwarf HD 13724 B
DOI: 10.1051/0004-6361/202037524 Bibcode: 2020A&A...635A.203R

Ségransan, D.; Delisle, J. -B.; Udry, S. +5 more

Context. HD 13724 is a nearby solar-type star at 43.48 ± 0.06 pc hosting a long-period low-mass brown dwarf detected with the CORALIE echelle spectrograph as part of the historical CORALIE radial-velocity search for extra-solar planets. The companion has a minimum mass of 26.77-2.2+4.4 MJup and an expected semi-maj…

2020 Astronomy and Astrophysics
Gaia 26
The GTC exoplanet transit spectroscopy survey. XI. Possible detection of Rayleigh scattering in the atmosphere of the Saturn-mass planet WASP-69b
DOI: 10.1051/0004-6361/202038161 Bibcode: 2020A&A...641A.158M

Nortmann, L.; Palle, E.; Nowak, G. +2 more

Context. One of the main atmospheric features in exoplanet atmospheres, detectable both from ground- and space-based facilities, is Rayleigh scattering. In hydrogen-dominated planetary atmospheres, Rayleigh scattering causes the measured planetary radius to increase toward blue wavelengths in the optical range.
Aims: We aim to detect and impr…

2020 Astronomy and Astrophysics
eHST 26
Orbital and spectral characterization of the benchmark T-type brown dwarf HD 19467B
DOI: 10.1051/0004-6361/202037984 Bibcode: 2020A&A...639A..47M

Henning, T.; Brandner, W.; Ségransan, D. +42 more

Context. Detecting and characterizing substellar companions for which the luminosity, mass, and age can be determined independently is of utter importance to test and calibrate the evolutionary models due to uncertainties in their formation mechanisms. HD 19467 is a bright and nearby star hosting a cool brown dwarf companion detected with radial v…

2020 Astronomy and Astrophysics
Gaia Hipparcos 26