Search Publications

Introducing the LBT Imaging of Galactic Halos and Tidal Structures (LIGHTS) survey. A preview of the low surface brightness Universe to be unveiled by LSST
DOI: 10.1051/0004-6361/202141603 Bibcode: 2021A&A...654A..40T

Trujillo, Ignacio; Sand, David J.; Zaritsky, Dennis +10 more

We present the first results of the LBT Imaging of Galaxy Haloes and Tidal Structures (LIGHTS) survey. LIGHTS is an ongoing observational campaign with the 2 × 8.4 m Large Binocular Telescope (LBT) aiming to explore the stellar haloes and the low surface brightness population of satellites down to a depth of µV ∼ 31 mag arcsec

2021 Astronomy and Astrophysics
Gaia 46
A Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE). IX. The effects of ram pressure stripping down to the scale of individual HII regions in the dwarf galaxy IC 3476
DOI: 10.1051/0004-6361/202039046 Bibcode: 2021A&A...646A.139B

Ferrarese, L.; Boquien, M.; Galbany, L. +25 more

We study the IB(s)m galaxy IC 3476 observed in the context of the Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE), a blind narrow-band Hα+[NII] imaging survey of the Virgo cluster carried out with MegaCam at the CFHT. The deep narrow-band image reveals a very pertubed ionised gas distribution that is characterised by a prominent …

2021 Astronomy and Astrophysics
Herschel 46
A planetary system with two transiting mini-Neptunes near the radius valley transition around the bright M dwarf TOI-776
DOI: 10.1051/0004-6361/202039455 Bibcode: 2021A&A...645A..41L

Fridlund, M.; Pallé, E.; Guenther, E. W. +63 more

We report the discovery and characterization of two transiting planets around the bright M1 V star LP 961-53 (TOI-776, J = 8.5 mag, M = 0.54 ± 0.03 M ) detected during Sector 10 observations of the Transiting Exoplanet Survey Satellite (TESS). Combining the TESS photometry with HARPS radial velocities, as well as ground-based follow-up…

2021 Astronomy and Astrophysics
Gaia 45
The Gaia-ESO survey: Mixing processes in low-mass stars traced by lithium abundance in cluster and field stars
DOI: 10.1051/0004-6361/202140935 Bibcode: 2021A&A...651A..84M

Baratella, M.; Gilmore, G.; Bayo, A. +42 more


Aims: We aim to constrain the mixing processes in low-mass stars by investigating the behaviour of the Li surface abundance after the main sequence. We take advantage of the data from the sixth internal data release of Gaia-ESO, IDR6, and from the Gaia Early Data Release 3, EDR3s.
Methods: We selected a sample of main-sequence, sub-giant…

2021 Astronomy and Astrophysics
Gaia 45
Long-term X-ray spectral evolution of ultraluminous X-ray sources: implications on the accretion flow geometry and the nature of the accretor
DOI: 10.1051/0004-6361/202039572 Bibcode: 2021A&A...649A.104G

Godet, O.; Webb, N.; Olive, J. -F. +2 more

Context. The discovery of pulsations in several ultraluminous X-ray sources (ULXs) has demonstrated that a fraction of them are powered by super-Eddington accretion onto neutron stars (NSs). This has raised questions regarding the NS to black hole (BH) ratio within the ULX population and the physical mechanism that allows ULXs to reach luminositie…

2021 Astronomy and Astrophysics
XMM-Newton 45
Effect of binary evolution on the inferred initial and final core masses of hydrogen-rich, Type II supernova progenitors
DOI: 10.1051/0004-6361/202037744 Bibcode: 2021A&A...645A...6Z

Smith, N.; Renzo, M.; Zapartas, E. +3 more

The majority of massive stars, which are the progenitors of core-collapse supernovae (SNe), are found in close binary systems. In a previous work, we modeled the fraction of hydrogen-rich, Type II SN progenitors whose evolution is affected by mass exchange with their companion, finding this to be between ≈1/3 and 1/2 for most assumptions. Here we …

2021 Astronomy and Astrophysics
eHST 45
CARMENES detection of the Ca II infrared triplet and possible evidence of He I in the atmosphere of WASP-76b
DOI: 10.1051/0004-6361/202141669 Bibcode: 2021A&A...654A.163C

Sánchez-López, A.; Snellen, I. A. G.; López-Puertas, M. +25 more

Ultra-hot Jupiters are highly irradiated gas giants with equilibrium temperatures typically higher than 2000 K. Atmospheric studies of these planets have shown that their transmission spectra are rich in metal lines, with some of these metals being ionised due to the extreme temperatures. Here, we use two transit observations of WASP-76b obtained …

2021 Astronomy and Astrophysics
XMM-Newton 45
Forever young white dwarfs: When stellar ageing stops
DOI: 10.1051/0004-6361/202140720 Bibcode: 2021A&A...649L...7C

Córsico, Alejandro H.; Rebassa-Mansergas, Alberto; Althaus, Leandro G. +5 more

White dwarf stars are the most common end point of stellar evolution. The ultramassive white dwarfs are of special interest as they are related to type Ia supernovae explosions, merger events, and fast radio bursts. Ultramassive white dwarfs are expected to harbour oxygen-neon (ONe) cores as a result of single standard stellar evolution. However, …

2021 Astronomy and Astrophysics
Gaia 44
The multiwavelength properties of red QSOs: Evidence for dusty winds as the origin of QSO reddening
DOI: 10.1051/0004-6361/202040214 Bibcode: 2021A&A...649A.102C

Alexander, D. M.; Bowler, R. A. A.; Stalevski, M. +11 more

Fundamental differences in the radio properties of red quasars (QSOs), as compared to blue QSOs, have been recently discovered, positioning them as a potential key population in the evolution of galaxies and black holes across cosmic time. To elucidate the nature of these objects, we exploited a rich compilation of broad-band photometry and spectr…

2021 Astronomy and Astrophysics
Herschel 44
Low-mass low-metallicity AGB stars as an efficient i-process site explaining CEMP-rs stars
DOI: 10.1051/0004-6361/202038891 Bibcode: 2021A&A...645A..61K

Jorissen, A.; Escorza, A.; Masseron, T. +5 more

Context. Among carbon-enhanced metal-poor (CEMP) stars, some are found to be enriched in slow-neutron capture (s-process) elements (and are then tagged CEMP-s), some have overabundances in rapid-neutron capture (r-process) elements (tagged CEMP-r), and some are characterized by both s- and r-process enrichments (tagged CEMP-rs). The current distin…

2021 Astronomy and Astrophysics
Gaia 44