Search Publications

Polarimetric imaging mode of VLT/SPHERE/IRDIS. II. Characterization and correction of instrumental polarization effects
DOI: 10.1051/0004-6361/201834996 Bibcode: 2020A&A...633A..64V

Ménard, F.; Henning, T.; Fantinel, D. +31 more

Context. Circumstellar disks and self-luminous giant exoplanets or companion brown dwarfs can be characterized through direct-imaging polarimetry at near-infrared wavelengths. SPHERE/IRDIS at the Very Large Telescope has the capabilities to perform such measurements, but uncalibrated instrumental polarization effects limit the attainable polarimet…

2020 Astronomy and Astrophysics
Gaia 113
The Solar Orbiter Radio and Plasma Waves (RPW) instrument
DOI: 10.1051/0004-6361/201936214 Bibcode: 2020A&A...642A..12M

Hellinger, P.; André, M.; Maksimovic, M. +103 more

The Radio and Plasma Waves (RPW) instrument on the ESA Solar Orbiter mission is described in this paper. This instrument is designed to measure in-situ magnetic and electric fields and waves from the continuous to a few hundreds of kHz. RPW will also observe solar radio emissions up to 16 MHz. The RPW instrument is of primary importance to the Sol…

2020 Astronomy and Astrophysics
SolarOrbiter 113
The Solar Orbiter SPICE instrument. An extreme UV imaging spectrometer
DOI: 10.1051/0004-6361/201935574 Bibcode: 2020A&A...642A..14S

Vial, J. -C.; Williams, D.; Peter, H. +87 more


Aims: The Spectral Imaging of the Coronal Environment (SPICE) instrument is a high-resolution imaging spectrometer operating at extreme ultraviolet wavelengths. In this paper, we present the concept, design, and pre-launch performance of this facility instrument on the ESA/NASA Solar Orbiter mission.
Methods: The goal of this paper is to…

2020 Astronomy and Astrophysics
SolarOrbiter 112
High-precision abundances of elements in solar-type stars. Evidence of two distinct sequences in abundance-age relations
DOI: 10.1051/0004-6361/202038300 Bibcode: 2020A&A...640A..81N

Christensen-Dalsgaard, J.; Spitoni, E.; Nissen, P. E. +3 more


Aims: Previous high-precision studies of abundances of elements in solar twin stars are extended to a wider metallicity range to see how the trends of element ratios with stellar age depend on [Fe/H].
Methods: HARPS spectra with signal-to-noise ratios S/N ≳ 600 at λ ∼ 6000 Å were analysed with MARCS model atmospheres to obtain 1D LTE abu…

2020 Astronomy and Astrophysics
Gaia 103
Photometric detection of internal gravity waves in upper main-sequence stars. II. Combined TESS photometry and high-resolution spectroscopy
DOI: 10.1051/0004-6361/202038224 Bibcode: 2020A&A...640A..36B

Simón-Díaz, S.; Aerts, C.; Bowman, D. M. +5 more

Context. Massive stars are predicted to excite internal gravity waves (IGWs) by turbulent core convection and from turbulent pressure fluctuations in their near-surface layers. These IGWs are extremely efficient at transporting angular momentum and chemical species within stellar interiors, but they remain largely unconstrained observationally.

2020 Astronomy and Astrophysics
Gaia 100
Galactic cirri in deep optical imaging
DOI: 10.1051/0004-6361/201936111 Bibcode: 2020A&A...644A..42R

Trujillo, Ignacio; Román, Javier; Montes, Mireia

The ubiquitous presence of Galactic cirri in deep optical images represents a major obstacle to study the low surface brightness features of extragalactic sources. To address this issue, we have explored the optical properties of cirri using g, r, i, and z bands in the Sloan Digital Sky Survey (SDSS) Stripe82 region. Using state-of-the-art, custom…

2020 Astronomy and Astrophysics
Herschel 99
Properties of the dense core population in Orion B as seen by the Herschel Gould Belt survey
DOI: 10.1051/0004-6361/201834753 Bibcode: 2020A&A...635A..34K

White, G. J.; André, Ph.; Arzoumanian, D. +15 more

We present a detailed study of the Orion B molecular cloud complex (d ~ 400 pc), which was imaged with the PACS and SPIRE photometric cameras at wavelengths from 70 to 500 µm as part of the Herschel Gould Belt survey (HGBS). We release new high-resolution maps of column density and dust temperature for the whole complex, derived in the same …

2020 Astronomy and Astrophysics
Herschel 99
Expected performances of the Characterising Exoplanet Satellite (CHEOPS). III. Data reduction pipeline: architecture and simulated performances
DOI: 10.1051/0004-6361/201936325 Bibcode: 2020A&A...635A..24H

Guterman, P.; Deleuil, M.; Benz, W. +4 more

The CHaracterizing ExOPlanet Satellite (CHEOPS) is set to be launched in December 2019 and will detect and characterize small size exoplanets via ultra high precision photometry during transits. CHEOPS is designed as a follow-up telescope and therefore it will monitor a single target at a time. The scientific users will retrieve science-ready ligh…

2020 Astronomy and Astrophysics
CHEOPS Gaia 99
A naked-eye triple system with a nonaccreting black hole in the inner binary
DOI: 10.1051/0004-6361/202038020 Bibcode: 2020A&A...637L...3R

Rivinius, Th.; Baade, D.; Klement, R. +2 more

Several dozen optical echelle spectra demonstrate that HR 6819 is a hierarchical triple. A classical Be star is in a wide orbit with an unconstrained period around an inner 40 d binary consisting of a B3 III star and an unseen companion in a circular orbit. The radial-velocity semi-amplitude of 61.3 km s-1 of the inne…

2020 Astronomy and Astrophysics
IUE 98
Observational constraints on the optical and near-infrared emission from the neutron star-black hole binary merger candidate S190814bv
DOI: 10.1051/0004-6361/202037669 Bibcode: 2020A&A...643A.113A

Covino, S.; D'Avanzo, P.; Campana, S. +151 more

Context. Gravitational wave (GW) astronomy has rapidly reached maturity, becoming a fundamental observing window for modern astrophysics. The coalescences of a few tens of black hole (BH) binaries have been detected, while the number of events possibly including a neutron star (NS) is still limited to a few. On 2019 August 14, the LIGO and Virgo i…

2020 Astronomy and Astrophysics
Gaia 97