Search Publications

Inspecting the Cepheid parallax of pulsation using Gaia EDR3 parallaxes. Projection factor and period-luminosity and period-radius relations
DOI: 10.1051/0004-6361/202141680 Bibcode: 2021A&A...656A.102T

Kervella, P.; Trahin, B.; Mérand, A. +5 more

Context. As primary anchors of the distance scale, Cepheid stars play a crucial role in our understanding of the distance scale of the Universe because of their period-luminosity relation. Determining precise and consistent parameters (radius, temperature, color excess, and projection factor) of Cepheid pulsating stars is therefore very important.…

2021 Astronomy and Astrophysics
Gaia 22
The EXTraS project: Exploring the X-ray transient and variable sky
DOI: 10.1051/0004-6361/202039783 Bibcode: 2021A&A...650A.167D

Salvaterra, R.; Haberl, F.; Greiner, J. +29 more

Temporal variability in flux and spectral shape is ubiquitous in the X-ray sky and carries crucial information about the nature and emission physics of the sources. The EPIC instrument on board the XMM-Newton observatory is the most powerful tool for studying variability even in faint sources. Each day, it collects a large amount of information ab…

2021 Astronomy and Astrophysics
XMM-Newton 22
Discovery of a recurrent spectral evolutionary cycle in the ultra-luminous X-ray sources Holmberg II X-1 and NGC 5204 X-1
DOI: 10.1051/0004-6361/202140781 Bibcode: 2021A&A...654A..10G

Vasilopoulos, G.; Godet, O.; Webb, N. A. +2 more

Context. Most ultra-luminous X-ray sources (ULXs) are now thought to be powered by stellar-mass compact objects accreting at super-Eddington rates. While the discovery of evolutionary cycles have marked a breakthrough in our understanding of the accretion flow changes in the sub-Eddington regime in Galactic black hole binaries, their evidence in t…

2021 Astronomy and Astrophysics
XMM-Newton eHST 22
Oort cloud Ecology. I. Extra-solar Oort clouds and the origin of asteroidal interlopers
DOI: 10.1051/0004-6361/202038888 Bibcode: 2021A&A...647A.136P

Portegies Zwart, S.

We simulate the formation and evolution of Oort clouds around the 200 nearest stars (within ∼16 pc according to the Gaia DR2) database. This study is performed by numerically integrating the planets and minor bodies in orbit around the parent star and in the Galactic potential. The calculations start 1 Gyr ago and continue for 100 Myr into the fut…

2021 Astronomy and Astrophysics
Gaia 22
The MURALES survey. IV. Searching for nuclear outflows in 3C radio galaxies at z < 0.3 with MUSE observations
DOI: 10.1051/0004-6361/202140686 Bibcode: 2021A&A...653A.150S

Marconi, A.; Capetti, A.; Grandi, P. +13 more

We analyze VLT/MUSE observations of 37 radio galaxies from the Third Cambridge catalogue (3C) with redshift < 0.3 searching for nuclear outflows of ionized gas. These observations are part of the MURALES project (a MUse RAdio Loud Emission line Snapshot survey), whose main goal is to explore the feedback process in the most powerful radio-loud …

2021 Astronomy and Astrophysics
eHST 22
Hoinga: a supernova remnant discovered in the SRG/eROSITA All-Sky Survey eRASS1
DOI: 10.1051/0004-6361/202040156 Bibcode: 2021A&A...648A..30B

Merloni, A.; Nicastro, L.; Becker, W. +4 more

Supernova remnants (SNRs) are observable for about (6−15) × 104 yr before they fade into the Galactic interstellar medium. With a Galactic supernova rate of approximately two per century, we can expect to have of the order of 1200 SNRs in our Galaxy. However, only about 300 of them are known to date, with the majority having been discov…

2021 Astronomy and Astrophysics
Gaia INTEGRAL 22
Distance and extinction to the Milky Way spiral arms along the Galactic centre line of sight
DOI: 10.1051/0004-6361/202040073 Bibcode: 2021A&A...653A..33N

Nogueras-Lara, F.; Neumayer, N.; Schödel, R.

Context. The position of the Sun inside the disc of the Milky Way significantly hampers the study of the spiral arm structure given the high amount of dust and gas along the line of sight, and the overall structure of this disc has therefore not yet been fully characterised.
Aims: We aim to analyse the spiral arms in the line of sight towards…

2021 Astronomy and Astrophysics
Gaia 22
The HD 98800 quadruple pre-main sequence system. Towards full orbital characterisation using long-baseline infrared interferometry
DOI: 10.1051/0004-6361/202141985 Bibcode: 2021A&A...655A..15Z

Bayo, A.; Olofsson, J.; Haubois, X. +8 more

Context. HD 98800 is a young (∼10 Myr old) and nearby (∼45 pc) quadruple system, composed of two spectroscopic binaries orbiting around each other (AaAb and BaBb), with a gas-rich disk in polar configuration around BaBb. While the orbital parameters of BaBb and AB are relatively well constrained, this is not the case for AaAb. A full characterisat…

2021 Astronomy and Astrophysics
Gaia 22
Multi-thermal atmosphere of a mini-solar flare during magnetic reconnection observed with IRIS
DOI: 10.1051/0004-6361/202039229 Bibcode: 2021A&A...645A..80J

Heinzel, Petr; Aulanier, Guillaume; Schmieder, Brigitte +4 more

Context. The Interface Region Imaging Spectrograph (IRIS) with its high spatial and temporal resolution facilitates exceptional plasma diagnostics of solar chromospheric and coronal activity during magnetic reconnection.
Aims: The aim of this work is to study the fine structure and dynamics of the plasma at a jet base forming a mini-flare bet…

2021 Astronomy and Astrophysics
IRIS 22
Confirmation and physical characterization of the new bulge globular cluster Patchick 99 from the VVV and Gaia surveys
DOI: 10.1051/0004-6361/202039255 Bibcode: 2021A&A...649A..86G

Minniti, D.; Ripepi, V.; Alonso-García, J. +4 more

Context. Globular clusters (GCs) are recognised as important tools for understanding the formation and evolution of the Milky Way (MW) because they are the oldest objects in our Galaxy. Unfortunately, the known sample in our MW is still incomplete, especially towards the innermost regions, because of the high differential reddening, extinction, an…

2021 Astronomy and Astrophysics
Gaia 22