Search Publications

Decoding the morphological evolution of open clusters
DOI: 10.1051/0004-6361/202141460 Bibcode: 2021A&A...656A..49H

Hu, Qingshun; Zhang, Yu; Esamdin, Ali

Context. The properties of open clusters such as metallicity, age, and morphology are useful tools in studies of the dynamic evolution of open clusters. The morphology of open clusters can help us better understand the evolution of such structures.
Aims: We aim to analyze the morphological evolution of 1256 open clusters by combining the shap…

2021 Astronomy and Astrophysics
Gaia 14
χ1 Fornacis cluster DANCe. Census of stars, structure, and kinematics of the cluster with Gaia-EDR3
DOI: 10.1051/0004-6361/202141366 Bibcode: 2021A&A...654A.122G

Miret-Roig, N.; Bouy, H.; Sarro, L. M. +4 more

Context. The χ1 Fornacis cluster (Alessi 13) is one of a few open clusters of its age and distance in the Solar neighbourhood that ought to benefit from more attention as it can serve as a cornerstone for numerous future studies related to star and planet formation.
Aims: We take advantage of the early installment of the third data…

2021 Astronomy and Astrophysics
Gaia 14
Molecular cloud catalogue from 13CO (1-0) data of the Forgotten Quadrant Survey
DOI: 10.1051/0004-6361/202141433 Bibcode: 2021A&A...654A.144B

Rygl, K. L. J.; Testi, L.; Benedettini, M. +13 more

Context. New-generation spectroscopic surveys of the Milky Way plane have been revealing the structure of the interstellar medium, allowing the simultaneous study of dense structures from single star-forming objects or systems to entire spiral arms.
Aims: The good sensitivity of the new surveys and the development of dedicated algorithms now …

2021 Astronomy and Astrophysics
Herschel 14
The kinematics of Small Magellanic Cloud star clusters
DOI: 10.1051/0004-6361/202140643 Bibcode: 2021A&A...650A..52P

Piatti, Andrés E.

We report results of the proper motions of 25 known Small Magellanic Cloud (SMC) clusters (ages ∼ 1-10 Gyr old) derived from Gaia EDR3 data sets. When these mean proper motions were gathered with existent radial velocity measurements to compose the clusters' velocity vectors, we found the parameter values of a rotation disk that best resemble thei…

2021 Astronomy and Astrophysics
Gaia 14
The SOPHIE search for northern extrasolar planets. XVII. A wealth of new objects: Six cool Jupiters, three brown dwarfs, and 16 low-mass binary stars
DOI: 10.1051/0004-6361/202140712 Bibcode: 2021A&A...651A..11D

Bouchy, F.; Deleuil, M.; Moutou, C. +30 more

Distinguishing classes within substellar objects and understanding their formation and evolution need larger samples of substellar companions such as exoplanets, brown dwarfs, and low-mass stars. In this paper, we look for substellar companions using radial velocity surveys of FGK stars with the SOPHIE spectrograph at the Observatoire de Haute-Pro…

2021 Astronomy and Astrophysics
Gaia Hipparcos 14
Time-dependent properties of sunspot groups. I. Lifetime and asymmetric evolution
DOI: 10.1051/0004-6361/202140731 Bibcode: 2021A&A...653A..50F

Forgács-Dajka, Emese; Dobos, László; Ballai, István


Aims: In this paper, we aim to study the time dependence of sunspot group areas in a large sample composed of various databases spanning over 130 years, used state-of-the-art statistical methods.
Methods: For a carefully selected but unbiased sample, we use Bayesian modelling to fit the temporal evolution of the combined umbral and penum…

2021 Astronomy and Astrophysics
SOHO 13
The metal-poor end of the Spite plateau. II. Chemical and dynamical investigation
DOI: 10.1051/0004-6361/202141288 Bibcode: 2021A&A...654A.170M

Steffen, M.; Bonifacio, P.; Caffau, E. +7 more

Context. The study of old, metal-poor stars deepens our knowledge on the early stages of the universe. In particular, the study of these stars gives us a valuable insight into the masses of the first massive stars and their emission of ionising photons.
Aims: We present a detailed chemical analysis and determination of the kinematic and orbit…

2021 Astronomy and Astrophysics
Gaia 13
Young giants of intermediate mass. Evidence of rotation and mixing
DOI: 10.1051/0004-6361/202141408 Bibcode: 2021A&A...656A.155L

Mucciarelli, Alessio; Meynet, Georges; Bonifacio, Piercarlo +7 more

Context. In the search of a sample of metal-poor bright giants using Strömgren photometry, we serendipitously found a sample of 26 young (ages younger than 1 Gyr) metal-rich giants, some of which have high rotational velocities.
Aims: We determined the chemical composition and rotational velocities of these stars in order to compare them with…

2021 Astronomy and Astrophysics
Gaia 13
ALMA resolves giant molecular clouds in a tidal dwarf galaxy
DOI: 10.1051/0004-6361/202038955 Bibcode: 2021A&A...645A..97Q

Moore, T. J. T.; Meidt, S. E.; Schinnerer, E. +12 more

Tidal dwarf galaxies (TDGs) are gravitationally bound condensations of gas and stars that formed during galaxy interactions. Here we present multi-configuration ALMA observations of J1023+1952, a TDG in the interacting system Arp 94, where we resolved CO(2-1) emission down to giant molecular clouds (GMCs) at 0.64″∼45 pc resolution. We find a remar…

2021 Astronomy and Astrophysics
Gaia eHST 13
Astrometric radial velocities for nearby stars
DOI: 10.1051/0004-6361/202141344 Bibcode: 2021A&A...652A..45L

Lindegren, Lennart; Dravins, Dainis

Context. Under certain conditions, stellar radial velocities can be determined from astrometry, without any use of spectroscopy. This enables us to identify phenomena, other than the Doppler effect, that are displacing spectral lines.
Aims: The change of stellar proper motions over time (perspective acceleration) is used to determine radial v…

2021 Astronomy and Astrophysics
Gaia Hipparcos 13