Search Publications

Revisiting the 16 Cygni planet host at unprecedented precision and exploring automated tools for precise abundances
DOI: 10.1051/0004-6361/201935952 Bibcode: 2019A&A...628A.126M

Spina, L.; Jofré, P.; Meléndez, J. +2 more

The binary system 16 Cygni is key in studies of the planet-star chemical composition connection, as only one of the stars is known to host a planet. This allows us to better assess the possible influence of planet interactions on the chemical composition of stars that are born from the same cloud and thus should have a similar abundance pattern. I…

2019 Astronomy and Astrophysics
Gaia 43
Detecting shocked intergalactic gas with X-ray and radio observations
DOI: 10.1051/0004-6361/201935439 Bibcode: 2019A&A...627A...5V

Ettori, S.; Roncarelli, M.; Vazza, F. +3 more

Detecting the thermal and non-thermal emission from the shocked cosmic gas surrounding large-scale structures represents a challenge for observations, as well as a unique window into the physics of the warm-hot intergalactic medium. In this work, we present synthetic radio and X-ray surveys of large cosmological simulations in order to assess the …

2019 Astronomy and Astrophysics
XMM-Newton 42
KiDS-SQuaD. II. Machine learning selection of bright extragalactic objects to search for new gravitationally lensed quasars
DOI: 10.1051/0004-6361/201936006 Bibcode: 2019A&A...632A..56K

Agnello, Adriano; Kuijken, Konrad; Spiniello, Chiara +9 more

Context. The KiDS Strongly lensed QUAsar Detection project (KiDS-SQuaD) is aimed at finding as many previously undiscovered gravitational lensed quasars as possible in the Kilo Degree Survey. This is the second paper of this series where we present a new, automatic object-classification method based on the machine learning technique.
Aims: Th…

2019 Astronomy and Astrophysics
Gaia 42
The survey of planetary nebulae in Andromeda (M 31). I. Imaging the disc and halo with MegaCam at the CFHT
DOI: 10.1051/0004-6361/201834579 Bibcode: 2019A&A...624A.132B

Caldwell, Nelson; Gerhard, Ortwin; Arnaboldi, Magda +4 more

Context. The Andromeda (M 31) galaxy subtends nearly 100 square degrees on the sky. Any study of its halo must therefore account for the severe contamination from the Milky Way halo stars whose surface density displays a steep gradient across the entire M 31 field of view.
Aims: Our goal is to identify a population of stars firmly associated …

2019 Astronomy and Astrophysics
eHST 42
When the tale comes true: multiple populations and wide binaries in the Orion Nebula Cluster
DOI: 10.1051/0004-6361/201935016 Bibcode: 2019A&A...627A..57J

Manara, Carlo F.; Petr-Gotzens, Monika G.; Boffin, Henri M. J. +5 more

Context. Recently published high-quality OmegaCAM photometry of the 3 × 3 deg around the Orion Nebula Cluster (ONC) in r, and i filters revealed three well-separated pre-main sequences in the color-magnitude diagram (CMD). The objects belonging to the individual sequences are concentrated toward the center of the ONC. The authors concluded that th…

2019 Astronomy and Astrophysics
Gaia 42
Distributed glycine in comet 67P/Churyumov-Gerasimenko
DOI: 10.1051/0004-6361/201935018 Bibcode: 2019A&A...630A..32H

Lasue, J.; Altwegg, K.; Biver, N. +10 more

Most of the gaseous molecules that are detected in cometary atmospheres are produced through sublimation of nucleus ices. Distributed sources may also occur, that is, production within the coma, from the solid component of dust particles that are ejected from the nucleus. Glycine, the simplest amino acid, was observed episodically in the atmospher…

2019 Astronomy and Astrophysics
Rosetta 42
Substructure and halo population of Double Cluster h and χ Persei
DOI: 10.1051/0004-6361/201834334 Bibcode: 2019A&A...624A..34Z

Chen, Li; Zhong, Jing; Li, Lu +3 more

Context. Gaia DR2 provides an ideal dataset to study the stellar populations of open clusters at larger spatial scales because the cluster member stars can be well identified by their location in the multidimensional observational parameter space with high precision parameter measurements.
Aims: In order to study the stellar population and po…

2019 Astronomy and Astrophysics
Gaia 41
The ALMA Lupus protoplanetary disk survey: evidence for compact gas disks and molecular rings from CN
DOI: 10.1051/0004-6361/201834257 Bibcode: 2019A&A...623A.150V

Testi, L.; Tazzari, M.; Williams, J. P. +10 more

Context. The cyanide radical CN is abundant in protoplanetary disks, with line fluxes often comparable to those of 13CO. It is known to be sensitive to UV irradiation of the upper disk atmosphere, with models predicting ring-shaped emission.
Aims: We seek to characterize the CN emission from 94 Class-II disks in the Lupus star-form…

2019 Astronomy and Astrophysics
Gaia 41
H-band discovery of additional second-generation stars in the Galactic bulge globular cluster NGC 6522 as observed by APOGEE and Gaia
DOI: 10.1051/0004-6361/201834391 Bibcode: 2019A&A...627A.178F

Schultheis, M.; Minniti, D.; Souto, Diogo +34 more

We present an elemental abundance analysis of high-resolution spectra for five giant stars spatially located within the innermost regions of the bulge globular cluster NGC 6522 and derive Fe, Mg, Al, C, N, O, Si, and Ce abundances based on H-band spectra taken with the multi-object APOGEE-north spectrograph from the SDSS-IV Apache Point Observator…

2019 Astronomy and Astrophysics
Gaia 41
Characterization and formation of on-disk spicules in the Ca II K and Mg II k spectral lines
DOI: 10.1051/0004-6361/201936617 Bibcode: 2019A&A...631L...5B

Joshi, Jayant; Rouppe van der Voort, Luc; Henriques, Vasco M. J. +1 more

We characterize, for the first time, type-II spicules in Ca II K 3934 Å using the CHROMIS instrument at the Swedish 1 m Solar Telescope. We find that their line formation is dominated by opacity shifts with the K3 minimum best representing the velocity of the spicules. The K2 features are either suppressed by the Doppler-shif…

2019 Astronomy and Astrophysics
IRIS 41