Search Publications
Evolution of the local spiral structure of the Milky Way revealed by open clusters
Hao, C. J.; Xu, Y.; Hou, L. G. +6 more
The structure and evolution of the spiral arms of our Milky Way are basic but long-standing questions in astronomy. In particular, the lifetime of spiral arms is still a puzzle and has not been well constrained from observations. In this work, we aim to inspect these issues using a large catalogue of open clusters. We compiled a catalogue of 3794 …
The luminous red nova AT 2018bwo in NGC 45 and its binary yellow supergiant progenitor
Gehrz, Robert D.; Bond, Howard E.; Burdge, Kevin B. +12 more
Luminous red novae (LRNe) are astrophysical transients associated with the partial ejection of a binary system's common envelope shortly before its merger. Here we present the results of our photometric and spectroscopic follow-up campaign of AT 2018bwo (DLT 18x), a LRN discovered in NGC 45, and investigate its progenitor system using binary stell…
3D dynamics of the Orion cloud complex. Discovery of coherent radial gas motions at the 100-pc scale
Meingast, Stefan; Alves, João; Großschedl, Josefa E. +1 more
We present the first study of the three-dimensional (3D) dynamics of the gas in the entire southern Orion cloud complex. We used the parallaxes and proper motions of young stellar objects (YSOs) from Gaia DR2 as a proxy for gas distance and proper motion, and the gas radial velocities from archival CO data, to compute the space motions of the diff…
Size and structures of disks around very low mass stars in the Taurus star-forming region
Pascucci, I.; Testi, L.; Scholz, A. +7 more
Context. The discovery of giant planets orbiting very low mass stars (VLMS) and the recent observed substructures in disks around VLMS is challenging planet formation models. Specifically, radial drift of dust particles is a catastrophic barrier in these disks, which prevents the formation of planetesimals and therefore planets.
Aims: We aim …
Low-redshift compact star-forming galaxies as analogues of high-redshift star-forming galaxies
Schaerer, D.; Thuan, T. X.; Izotov, Y. I. +3 more
We compare the relations among various integrated characteristics of ∼25 000 low-redshift (z ≲ 1.0) compact star-forming galaxies (CSFGs) from Data Release 16 (DR16) of the Sloan Digital Sky Survey and of high-redshift (z ≳ 1.5) star-forming galaxies (SFGs) with respect to oxygen abundances, stellar masses M⋆, far-UV absolute magnitudes…
The parallax zero-point offset from Gaia EDR3 data
Groenewegen, M. A. T.
The second data release of Gaia revealed a parallax zero-point offset of −0.029 mas based on quasars. The value depended on the position on the sky, and also likely on magnitude and colour. The offset and its dependence on other parameters inhibited improvement in the local distance scale using for example the Cepheid and RR Lyrae period-luminosit…
Medium-resolution spectrum of the exoplanet HIP 65426 b
D'Orazi, V.; Boccaletti, A.; Lagrange, A. -M. +18 more
Medium-resolution integral-field spectrographs (IFS) coupled with adaptive-optics such as Keck/OSIRIS, VLT/MUSE, or SINFONI are appearing as a new avenue for enhancing the detection and characterization capabilities of young, gas giant exoplanets at large heliocentric distances (>5 au). We analyzed K-band VLT/SINFONI medium-resolution (Rλ<…
Ultra diffuse galaxies in the MATLAS low-to-moderate density fields
Müller, Oliver; Duc, Pierre-Alain; Lim, Sungsoon +10 more
Recent advances in deep dedicated imaging surveys over the past decade have uncovered a surprisingly large number of extremely faint low surface brightness galaxies with large physical sizes called ultra diffuse galaxies (UDGs) in clusters and, more recently, in lower density environments. As part of the Mass Assembly of early-Type GaLAxies with t…
Abundance-age relations with red clump stars in open clusters
Jordi, C.; Casamiquela, L.; Balaguer-Núñez, L. +8 more
Context. Precise chemical abundances coupled with reliable ages are key ingredients to understanding the chemical history of our Galaxy. Open clusters (OCs) are useful for this purpose because they provide ages with good precision.
Aims: The aim of this work is to investigate the relation between different chemical abundance ratios and age tr…
The Gaia-ESO Survey: Galactic evolution of lithium from iDR6
Montes, D.; de Laverny, P.; Guiglion, G. +31 more
Context. After more than 50 years, astronomical research still struggles to reconstruct the history of lithium enrichment in the Galaxy and to establish the relative importance of the various 7Li sources in enriching the interstellar medium (ISM) with this fragile element.
Aims: To better trace the evolution of lithium in the Milky…