Search Publications

Three planets transiting the evolved star EPIC 249893012: a hot 8.8-M super-Earth and two warm 14.7 and 10.2-M sub-Neptunes
DOI: 10.1051/0004-6361/201937080 Bibcode: 2020A&A...636A..89H

Kuzuhara, M.; Alonso, R.; Erikson, A. +57 more

We report the discovery of a new planetary system with three transiting planets, one super-Earth and two sub-Neptunes, that orbit EPIC 249893012, a G8 IV-V evolved star (M = 1.05 ± 0.05 M, R = 1.71 ± 0.04 R, Teff = 5430 ± 85 K). The star is just leaving the main sequence. We combined K2 ph…

2020 Astronomy and Astrophysics
Gaia 19
The VANDELS survey: Discovery of massive overdensities of galaxies at z > 2. Location of Lyα-emitting galaxies with respect to environment
DOI: 10.1051/0004-6361/201935855 Bibcode: 2020A&A...640A.107G

Bauer, F. E.; Thomas, R.; Bolzonella, M. +19 more

Context. The advent of deep, multi-wavelength surveys, together with the availability of extensive numerical simulations, now allow us for the systematic search and study of (proto)clusters and their surrounding environment as a function of redshift.
Aims: We aim to define the environment and to identify overdensities in the VANDELS Chandra D…

2020 Astronomy and Astrophysics
eHST 18
High-resolution, 3D radiative transfer modelling. V. A detailed model of the M 51 interacting pair
DOI: 10.1051/0004-6361/202038939 Bibcode: 2020A&A...643A..90N

Clark, Christopher J. R.; Mosenkov, Aleksandr V.; De Looze, Ilse +13 more

Context. Investigating the dust heating mechanisms in galaxies provides a deeper understanding of how the internal energy balance drives their evolution. Over the last decade radiative transfer simulations based on the Monte Carlo method have emphasised the role of the various stellar populations heating the diffuse dust. Beyond the expected heati…

2020 Astronomy and Astrophysics
Herschel 18
A new take on the low-mass brown dwarf companions on wide orbits in Upper-Scorpius
DOI: 10.1051/0004-6361/201935732 Bibcode: 2020A&A...633A.124P

Bayo, A.; Babusiaux, C.; Janson, M. +10 more

Context. The Upper-Scorpius association (5-11 Myr) contains a unique population of low-mass (M ≤ 30MJup) brown dwarfs either free-floating, forming wide pairs, or on wide orbits around solar-type and massive stars. The detailed relative characterization of their physical properties (mass, radius, temperature, composition, and ongoing ac…

2020 Astronomy and Astrophysics
Gaia 18
ALMA and VLA reveal the lukewarm chromospheres of the nearby red supergiants Antares and Betelgeuse
DOI: 10.1051/0004-6361/202037756 Bibcode: 2020A&A...638A..65O

Ryde, N.; Feeney-Johansson, A.; Lim, J. +8 more

We first present spatially resolved ALMA and VLA continuum observations of the early-M red supergiant Antares to search for the presence of a chromosphere at radio wavelengths. We resolve the free-free emission of the Antares atmosphere at 11 unique wavelengths between 0.7 mm (ALMA band 8) and 10 cm (VLA S band). The projected angular diameter is …

2020 Astronomy and Astrophysics
eHST 18
Disc-binary interactions in depleted post-AGB binaries
DOI: 10.1051/0004-6361/202038341 Bibcode: 2020A&A...642A.234O

Van Winckel, Hans; Nelemans, Gijs; Pols, Onno +1 more

Binary post-asymptotic giant branch (post-AGB) stars have orbital periods in the range of 100-2500 days in eccentric orbits. They are surrounded by circumbinary dusty discs. They are the immediate result of unconstrained binary interaction processes. Their observed orbital properties do not correspond to model predictions: Neither the periods nor …

2020 Astronomy and Astrophysics
Gaia 18
A new method for measuring the meteor mass index: application to the 2018 Draconid meteor shower outburst
DOI: 10.1051/0004-6361/201937296 Bibcode: 2020A&A...635A.153V

Vida, D.; Campbell-Brown, M.; Brown, P. G. +2 more

Context. Several authors predicted an outburst of the Draconid meteor shower in 2018, but with an uncertain level of activity.
Aims: Optical meteor observations were used to derive the population and mass indices, flux, and radiant positions of Draconid meteors.
Methods: We performed 90 min of multi-station observations after the predict…

2020 Astronomy and Astrophysics
Gaia 18
Unveiling pure-metal ejecta X-ray emission in supernova remnants through their radiative recombination continuum
DOI: 10.1051/0004-6361/202038092 Bibcode: 2020A&A...638A.101G

Greco, Emanuele; Vink, Jacco; Miceli, Marco +5 more

Context. Spectral analysis of X-ray emission from ejecta in supernova remnants (SNRs) is hampered by the low spectral resolution of CCD detectors, which typically creates a degeneracy between the best-fit values of chemical abundances and the plasma emission measure. The combined contribution of shocked ambient medium and ejecta to the emerging X-…

2020 Astronomy and Astrophysics
XMM-Newton 18
The abundance of S- and Si-bearing molecules in O-rich circumstellar envelopes of AGB stars
DOI: 10.1051/0004-6361/202037900 Bibcode: 2020A&A...641A..57M

Cernicharo, J.; Agúndez, M.; Velilla-Prieto, L. +1 more


Aims: We aim to determine the abundances of SiO, CS, SiS, SO, and SO2 in a large sample of oxygen-rich asymptotic giant branch (AGB) envelopes covering a wide range of mass loss rates to investigate the potential role that these molecules could play in the formation of dust in these environments.
Methods: We surveyed a sample …

2020 Astronomy and Astrophysics
Gaia 18
Characteristics of solar wind suprathermal halo electrons
DOI: 10.1051/0004-6361/202038830 Bibcode: 2020A&A...642A.130L

Fichtner, H.; Pierrard, V.; Lazar, M. +1 more

A suprathermal halo population of electrons is ubiquitous in space plasmas, as evidence of their departure from thermal equilibrium even in the absence of anisotropies. The origin, properties, and implications of this population, however, are poorly known. We provide a comprehensive description of solar wind halo electrons in the ecliptic, contras…

2020 Astronomy and Astrophysics
Cluster Ulysses 18