Search Publications

The Chandra view of the relation between X-ray and UV emission in quasars
DOI: 10.1051/0004-6361/202140852 Bibcode: 2021A&A...655A.109B

Civano, F.; Elvis, M.; Fabbiano, G. +4 more

We present a study of the relation between X-rays and ultraviolet emission in quasars for a sample of broad-line, radio-quiet objects obtained from the cross-match of the Sloan Digital Sky Survey DR14 with the latest Chandra Source Catalog 2.0 (2332 quasars) and the Chandra COSMOS Legacy survey (273 quasars). The non-linear relation between the ul…

2021 Astronomy and Astrophysics
XMM-Newton 32
C18O, 13CO, and 12CO abundances and excitation temperatures in the Orion B molecular cloud. Analysis of the achievable precision in modeling spectral lines within the approximation of the local thermodynamic equilibrium
DOI: 10.1051/0004-6361/202037776 Bibcode: 2021A&A...645A..26R

Peretto, Nicolas; Hughes, Annie; Kainulainen, Jouni +23 more

Context. CO isotopologue transitions are routinely observed in molecular clouds for the purpose of probing the column density of the gas and the elemental ratios of carbon and oxygen, in addition to tracing the kinematics of the environment.
Aims: Our study is aimed at estimating the abundances, excitation temperatures, velocity field, and ve…

2021 Astronomy and Astrophysics
Herschel 32
Multi-point analysis of coronal mass ejection flux ropes using combined data from Solar Orbiter, BepiColombo, and Wind
DOI: 10.1051/0004-6361/202140919 Bibcode: 2021A&A...656A..13W

Möstl, C.; Horbury, T. S.; Baumjohann, W. +15 more

Context. The recent launch of Solar Orbiter and the flyby of BepiColombo opened a brief window during which these two spacecraft, along with the existing spacecraft at L1, were positioned in a constellation that allowed for the detailed sampling of any Earth-directed coronal mass ejection (CME). Fortunately, two such events occurred during this ti…

2021 Astronomy and Astrophysics
BepiColombo SolarOrbiter 32
KiDS-1000: Constraints on the intrinsic alignment of luminous red galaxies
DOI: 10.1051/0004-6361/202140706 Bibcode: 2021A&A...654A..76F

Hoekstra, Henk; Heymans, Catherine; Kuijken, Konrad +11 more

We constrain the luminosity and redshift dependence of the intrinsic alignment (IA) of a nearly volume-limited sample of luminous red galaxies selected from the fourth public data release of the Kilo-Degree Survey (KiDS-1000). To measure the shapes of the galaxies, we used two complementary algorithms, finding consistent IA measurements for the ov…

2021 Astronomy and Astrophysics
eHST 32
TOI-674b: An oasis in the desert of exo-Neptunes transiting a nearby M dwarf
DOI: 10.1051/0004-6361/202140718 Bibcode: 2021A&A...653A..60M

Bouchy, F.; Korth, J.; Doyon, R. +59 more

Context. The NASA mission TESS is currently doing an all-sky survey from space to detect transiting planets around bright stars. As part of the validation process, the most promising planet candidates need to be confirmed and characterized using follow-up observations.
Aims: In this article, our aim is to confirm the planetary nature of the t…

2021 Astronomy and Astrophysics
Gaia 32
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