Search Publications

Search for flares and associated CMEs on late-type main-sequence stars in optical SDSS spectra
DOI: 10.1051/0004-6361/202039003 Bibcode: 2021A&A...646A..34K

Temmer, Manuela; Veronig, Astrid; Beck, Paul G. +3 more


Aims: This work aims to detect and classify stellar flares and potential stellar coronal mass ejection (CME) signatures in optical spectra provided by the Sloan Digital Sky Survey (SDSS) data release 14. The sample is constrained to all F, G, K, and M main-sequence type stars, resulting in more than 630 000 stars. This work makes use of the i…

2021 Astronomy and Astrophysics
Gaia 35
The MUSE-Faint survey. II. The dark-matter density profile of the ultra-faint dwarf galaxy Eridanus 2
DOI: 10.1051/0004-6361/202040239 Bibcode: 2021A&A...651A..80Z

Brinchmann, Jarle; Maseda, Michael V.; Krajnović, Davor +5 more


Aims: We use stellar line-of-sight velocities to constrain the dark-matter density profile of Eridanus 2, an ultra-faint dwarf galaxy with an absolute V-band magnitude MV = −7.1 that corresponds to a stellar mass M* ≈ 9 × 104 M. We furthermore derive constraints on fundamental properties of self-in…

2021 Astronomy and Astrophysics
Gaia eHST 35
Planetary nebulae in Gaia EDR3: Central star identification, properties, and binarity
DOI: 10.1051/0004-6361/202141916 Bibcode: 2021A&A...656A..51G

Dafonte, C.; González-Santamaría, I.; Manteiga, M. +3 more

Context. The Gaia Early Data Release 3 (EDR3), published in December 2020, features improved photometry and astrometry compared to that published in the previous DR2 file and includes a substantially larger number of sources, of the order of 2000 million, making it a paradigm of big data astronomy. Many of the central stars of planetary nebulae (C…

2021 Astronomy and Astrophysics
Gaia 35
A giant X-ray dust scattering ring discovered with SRG/eROSITA around the black hole transient MAXI J1348-630
DOI: 10.1051/0004-6361/202039757 Bibcode: 2021A&A...647A...7L

Wilms, J.; Predehl, P.; Freyberg, M. +3 more

We report the discovery of a giant dust scattering ring around the Black Hole transient MAXI J1348-630 with SRG/eROSITA during its first X-ray all-sky survey. During the discovery observation in February 2020, the ring had an outer diameter of 1.3 deg, growing to 1.6 deg by the time of the second all-sky survey scan in August 2020. This makes the …

2021 Astronomy and Astrophysics
Gaia XMM-Newton 35
Search for associations containing young stars (SACY). VIII. An updated census of spectroscopic binary systems exhibiting hints of non-universal multiplicity among their associations
DOI: 10.1051/0004-6361/202037830 Bibcode: 2021A&A...645A..30Z

Bayo, A.; Huélamo, N.; Sterzik, M. F. +10 more

Context. Nearby young associations offer one of the best opportunities for a detailed study of the properties of young stellar and substellar objects thanks to their proximity (<200 pc) and age (∼5-150 Myr). Previous works have identified spectroscopic (<5 au) binaries, close (5-1000 au) visual binaries, and wide or extremely wide (1000-100 …

2021 Astronomy and Astrophysics
Gaia 34
The survey of planetary nebulae in Andromeda (M 31). III. Constraints from deep planetary nebula luminosity functions on the origin of the inner halo substructures in M 31
DOI: 10.1051/0004-6361/202038366 Bibcode: 2021A&A...647A.130B

Caldwell, Nelson; Freeman, Kenneth C.; Gerhard, Ortwin +4 more

Context. The Andromeda (M 31) galaxy displays several substructures in its inner halo. Different simulations associate their origin with either a single relatively massive merger, or with a larger number of distinct, less massive accretions.
Aims: The origin of these substructures as remnants of accreted satellites or perturbations of the pre…

2021 Astronomy and Astrophysics
eHST 34
Convective blueshift strengths of 810 F to M solar-type stars
DOI: 10.1051/0004-6361/202039607 Bibcode: 2021A&A...654A.168L

Reiners, A.; Zechmeister, M.; Jeffers, S. V. +1 more

Context. The detection of Earth-mass exoplanets in the habitable zone around solar-mass stars using the radial velocity technique requires extremely high precision, on the order of 10 cm s−1. This puts the required noise floor below the intrinsic variability of even relatively inactive stars, such as the Sun. One such variable is convec…

2021 Astronomy and Astrophysics
Gaia 34
Revisiting the archetypical wind accretor Vela X-1 in depth. Case study of a well-known X-ray binary and the limits of our knowledge
DOI: 10.1051/0004-6361/202040272 Bibcode: 2021A&A...652A..95K

Degenaar, N.; Utrilla, E.; Ramos-Lerate, M. +9 more

Context. The Vela X-1 system is one of the best-studied X-ray binaries because it was detected early, has persistent X-ray emission, and a rich phenomenology at many wavelengths. The system is frequently quoted as the archetype of wind-accreting high-mass X-ray binaries, and its parameters are referred to as typical examples. Specific values for t…

2021 Astronomy and Astrophysics
Exosat Gaia INTEGRAL 34
Multi-instrumental view of magnetic fields and activity of ɛ Eridani with SPIRou, NARVAL, and TESS
DOI: 10.1051/0004-6361/202040027 Bibcode: 2021A&A...648A..55P

Donati, J. -F.; Petit, P.; Vidotto, A. A. +6 more


Aims: We report on observations of the active K2 dwarf ɛ Eridani based on contemporaneous SPIRou, NARVAL and TESS data obtained over two months in late 2018, when the activity of the star was reported to be in a non-cyclic phase.
Methods: Near-infrared (NIR) spectropolarimetry was obtained using SPIRou over four nights in late September,…

2021 Astronomy and Astrophysics
Gaia 33
One star, two star, red star, blue star: an updated planetary nebula central star distance catalogue from Gaia EDR3
DOI: 10.1051/0004-6361/202142008 Bibcode: 2021A&A...656A.110C

Walton, N. A.; Chornay, N.

Context. Planetary nebulae (PNe) are a brief but important phase of stellar evolution. The study of Galactic PNe has historically been hampered by uncertain distances, but the parallaxes of PN central stars (CSPNe) measured by Gaia are improving the situation.
Aims: Gaia's Early Data Release 3 (EDR3) offers higher astrometric precision and gr…

2021 Astronomy and Astrophysics
Gaia eHST 33