Search Publications

3D chemical structure of diffuse turbulent ISM. I. Statistics of the HI-to-H2 transition
DOI: 10.1051/0004-6361/202038593 Bibcode: 2020A&A...643A..36B

Godard, B.; Pérault, M.; Hennebelle, P. +4 more

Context. The amount of data collected by spectrometers from radio to ultraviolet (UV) wavelengths opens a new era where the statistical and chemical information contained in the observations can be used concomitantly to investigate the thermodynamical state and the evolution of the interstellar medium (ISM).
Aims: In this paper, we study the …

2020 Astronomy and Astrophysics
Gaia 31
Trimodal structure of Hercules stream explained by originating from bar resonances
DOI: 10.1093/mnras/staa2849 Bibcode: 2020MNRAS.499.2416A

Portegies Zwart, S.; Asano, Tetsuro; Fujii, M. S. +3 more

Gaia Data Release 2 revealed detailed structures of nearby stars in phase space. These include the Hercules stream, whose origin is still debated. Most of the previous numerical studies conjectured that the observed structures originate from orbits in resonance with the bar, based on static potential models for the Milky Way. We, in contrast, appr…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 31
A Suzaku sample of unabsorbed narrow-line and broad-line Seyfert 1 galaxies - I. X-ray spectral properties
DOI: 10.1093/mnras/staa2783 Bibcode: 2020MNRAS.498.5207W

Gallo, L. C.; Waddell, S. G. H.

A sample of narrow-line Seyfert 1 (NLS1) and broad-line Seyfert 1 (BLS1) galaxies observed with Suzaku is presented. The final sample consists of 22 NLS1s and 47 BLS1s, for a total of 69 active galactic nuclei (AGNs) that are all at low redshift (z < 0.5) and exhibit low host-galaxy column densities (<1022 ${\rm cm}^{-2}\,$ ). The…

2020 Monthly Notices of the Royal Astronomical Society
Suzaku 31
HST/STIS transmission spectrum of the ultra-hot Jupiter WASP-76 b confirms the presence of sodium in its atmosphere
DOI: 10.1051/0004-6361/201937169 Bibcode: 2020A&A...637A..76V

Mallonn, M.; Kjeldsen, H.; von Essen, C. +4 more

We present an atmospheric transmission spectrum of the ultra-hot Jupiter WASP-76 b by analyzing archival data obtained with the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope (HST). The dataset spans three transits, two with a wavelength coverage between 2900 and 5700 Å, and the third one between 5250 and 10 300 Å.…

2020 Astronomy and Astrophysics
eHST 31
The Gaia-ESO Survey: membership probabilities for stars in 32 open clusters from 3D kinematics
DOI: 10.1093/mnras/staa1749 Bibcode: 2020MNRAS.496.4701J

Gilmore, G.; Bayo, A.; Cantat-Gaudin, T. +16 more

The Gaia-ESO Survey (GES) observed many open clusters as part of its programme to spectroscopically characterize the various Milky Way populations. GES spectroscopy and Gaia astrometry from its second data release are used here to assign membership probabilities to targets towards 32 open clusters with ages from 1 to 3800 Myr, based on maximum lik…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 31
Probing the extragalactic fast transient sky at minute time-scales with DECam
DOI: 10.1093/mnras/stz3381 Bibcode: 2020MNRAS.491.5852A

Lien, A.; Cucchiara, A.; Wolf, C. +22 more

Searches for optical transients are usually performed with a cadence of days to weeks, optimized for supernova discovery. The optical fast transient sky is still largely unexplored, with only a few surveys to date having placed meaningful constraints on the detection of extragalactic transients evolving at sub-hour time-scales. Here, we present th…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 31
Peculiar Solar Sources and Geospace Disturbances on 20-26 August 2018
DOI: 10.1007/s11207-019-1574-8 Bibcode: 2020SoPh..295....7A

Chertok, I. M.; Belov, A. V.; Abunina, M. A. +1 more

On the approach to minimum of Solar Cycle 24, on 26 August 2018, an unexpectedly strong geomagnetic storm (GMS) suddenly occurred. Its Dst index reached −174 nT, that is, the third most intense storm of the cycle. The analysis showed that it was initiated by a two-step long filament eruption, which occurred on 20 August in the central s…

2020 Solar Physics
SOHO 31
Formation channels of slowly rotating early-type galaxies
DOI: 10.1051/0004-6361/201937040 Bibcode: 2020A&A...635A.129K

Krajnović, Davor; Emsellem, Eric; Cappellari, Michele +11 more

We study the evidence for a diversity of formation processes in early-type galaxies by presenting the first complete volume-limited sample of slow rotators with both integral-field kinematics from the ATLAS3D Project and high spatial resolution photometry from the Hubble Space Telescope. Analysing the nuclear surface brightness profiles…

2020 Astronomy and Astrophysics
eHST 31
Probing the magnetospheric accretion region of the young pre-transitional disk system DoAr 44 using VLTI/GRAVITY
DOI: 10.1051/0004-6361/202037611 Bibcode: 2020A&A...636A.108B

Dougados, C.; Bouvier, J.; Brandner, W. +6 more

Context. Young stellar objects are thought to accrete material from their circumstellar disks through their strong stellar magnetospheres.
Aims: We aim to directly probe the magnetospheric accretion region on a scale of a few 0.01 au in a young stellar system using long-baseline optical interferometry.
Methods: We observed the pre-transi…

2020 Astronomy and Astrophysics
Gaia 31
Temperature profiles of young disk-like structures. The case of IRAS 16293A
DOI: 10.1051/0004-6361/201936839 Bibcode: 2020A&A...633A...7V

van Dishoeck, Ewine F.; Jørgensen, Jes K.; van 't Hoff, Merel L. R. +1 more

Context. Temperature is a crucial parameter in circumstellar disk evolution and planet formation because it governs the resistance of the gas to gravitational instability and sets the chemical composition of the planet-forming material.
Aims: We set out to determine the gas temperature of the young disk-like structure around the Class 0 proto…

2020 Astronomy and Astrophysics
ISO 31