Search Publications

Direct characterization of young giant exoplanets at high spectral resolution by coupling SPHERE and CRIRES+
DOI: 10.1051/0004-6361/202038517 Bibcode: 2021A&A...646A.150O

Reiners, A.; Lopez, M.; Costille, A. +19 more

Studies of atmospheres of directly imaged extrasolar planets with high-resolution spectrographs have shown that their characterization is predominantly limited by noise on the stellar halo at the location of the studied exoplanet. An instrumental combination of high-contrast imaging and high spectral resolution that suppresses this noise and resol…

2021 Astronomy and Astrophysics
Hipparcos 31
Taking snapshots of the jet-ISM interplay: The case of PKS 0023-26
DOI: 10.1051/0004-6361/202141766 Bibcode: 2021A&A...656A..55M

Morganti, Raffaella; Oosterloo, Tom; Tadhunter, Clive +2 more

We present high angular resolution (0.13-0.4 arcsec) ALMA CO(2-1) and 1.7 mm continuum observations of the far-infrared-bright galaxy PKS 0023−26 (z = 0.32), which hosts a young radio source as well as a luminous optical active galactic nucleus (AGN). Although young, the powerful radio source has already grown to a size of a few kiloparsec, making…

2021 Astronomy and Astrophysics
eHST 31
Jellyfish galaxy candidates in MACS J0717.5+3745 and 39 other clusters of the DAFT/FADA and CLASH surveys
DOI: 10.1051/0004-6361/202039770 Bibcode: 2021A&A...648A..63D

Durret, F.; Jauzac, M.; Lobo, C. +1 more

Context. Galaxies in clusters undergo several phenomena, such as RPS and tidal interactions, that can trigger or quench their star formation and, in some cases, lead to galaxies acquiring unusual shapes and long tails - some become jellyfish.
Aims: We searched for jellyfish galaxy candidates in a sample of 40 clusters from the DAFT/FADA and C…

2021 Astronomy and Astrophysics
eHST 31
The GRAVITY young stellar object survey. VII. The inner dusty disks of T Tauri stars
DOI: 10.1051/0004-6361/202141624 Bibcode: 2021A&A...655A..73G

Lutz, D.; Genzel, R.; Sturm, E. +55 more

Context. T Tauri stars are surrounded by dust and gas disks. As material reservoirs from which matter is accreted onto the central star and planets are built, these protoplanetary disks play a central role in star and planet formation.
Aims: We aim at spatially resolving at sub-astronomical unit (sub-au) scales the innermost regions of the pr…

2021 Astronomy and Astrophysics
Gaia 31
Determining the true mass of radial-velocity exoplanets with Gaia. Nine planet candidates in the brown dwarf or stellar regime and 27 confirmed planets
DOI: 10.1051/0004-6361/202039168 Bibcode: 2021A&A...645A...7K

Lecavelier des Etangs, A.; Vidal-Madjar, A.; Kiefer, F. +3 more

Mass is one of the most important parameters for determining the true nature of an astronomical object. Yet, many published exoplanets lack a measurement of their true mass, in particular those detected as a result of radial-velocity (RV) variations of their host star. For those examples, only the minimum mass, or m sin i, is known, owing to the i…

2021 Astronomy and Astrophysics
Gaia eHST 31
A highly non-Keplerian protoplanetary disc. Spiral structure in the gas disc of CQ Tau
DOI: 10.1051/0004-6361/202039469 Bibcode: 2021A&A...648A..19W

Lodato, G.; Testi, L.; Facchini, S. +9 more

Context. In recent years high-angular-resolution observations have revealed that circumstellar discs appear in a variety of shapes with diverse substructures being ubiquitous. This has given rise to the question of whether these substructures are triggered by planet-disc interactions. Besides direct imaging, one of the most promising methods to di…

2021 Astronomy and Astrophysics
Gaia 31
Determination of the escape velocity of the Milky Way using a halo sample selected based on proper motion
DOI: 10.1051/0004-6361/202038777 Bibcode: 2021A&A...649A.136K

Helmi, Amina; Koppelman, Helmer H.

Context. The Gaia mission has provided the largest catalogue ever of sources with tangential velocity information. However, it is difficult to use this catalogue for dynamical studies because most of the stars lack line-of-sight velocity measurements. Recently, we presented a selection of ∼107 halo stars with accurate distances that wer…

2021 Astronomy and Astrophysics
Gaia 31
Extreme ultra-soft X-ray variability in an eROSITA observation of the narrow-line Seyfert 1 galaxy 1H 0707-495
DOI: 10.1051/0004-6361/202039316 Bibcode: 2021A&A...647A...6B

Buchner, J.; Nandra, K.; Merloni, A. +9 more

The ultra-soft narrow-line Seyfert 1 galaxy 1H 0707-495 is a well-known and highly variable active galactic nucleus (AGN), with a complex, steep X-ray spectrum, and has been studied extensively with XMM-Newton. 1H 0707-495 was observed with the extended ROentgen Survey with an Imaging Telescope Array (eROSITA) aboard the Spectrum-Roentgen-Gamma (S…

2021 Astronomy and Astrophysics
XMM-Newton 30
BEAST begins: sample characteristics and survey performance of the B-star Exoplanet Abundance Study
DOI: 10.1051/0004-6361/202039683 Bibcode: 2021A&A...646A.164J

Henning, Thomas; Reffert, Sabine; Langlois, Maud +20 more

While the occurrence rate of wide giant planets appears to increase with stellar mass at least up through the A-type regime, B-type stars have not been systematically studied in large-scale surveys so far. It therefore remains unclear up to what stellar mass this occurrence trend continues. The B-star Exoplanet Abundance Study (BEAST) is a direct …

2021 Astronomy and Astrophysics
Gaia 30
Modelling a multi-spacecraft coronal mass ejection encounter with EUHFORIA
DOI: 10.1051/0004-6361/202140315 Bibcode: 2021A&A...652A..27A

Palmerio, E.; Temmer, M.; Poedts, S. +6 more

Context. Coronal mass ejections (CMEs) are a manifestation of the Sun's eruptive nature. They can have a great impact on Earth, but also on human activity in space and on the ground. Therefore, modelling their evolution as they propagate through interplanetary space is essential.
Aims: EUropean Heliospheric FORecasting Information Asset (EUHF…

2021 Astronomy and Astrophysics
SOHO VenusExpress 30