Search Publications
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…
The VANDELS survey: The relation between the UV continuum slope and stellar metallicity in star-forming galaxies at z ∼ 3
Cimatti, A.; Schaerer, D.; Franco, M. +23 more
The estimate of stellar metallicities (Z*) of high-z galaxies are of paramount importance in order to understand the complexity of dust effects and the reciprocal interrelations among stellar mass, dust attenuation, stellar age, and metallicity. Benefiting from uniquely deep far-UV spectra of > 500 star-forming galaxies at redshifts …
The ALPINE-ALMA [CII] survey. The contribution of major mergers to the galaxy mass assembly at z ∼ 5
Cimatti, A.; Rodighiero, G.; Schaerer, D. +25 more
Context. Galaxy mergers are thought to be one of the main mechanisms of the mass assembly of galaxies in the Universe, but there is still little direct observational evidence of how frequent they are at z ≳ 4. Recently, many works have suggested a possible increase in the fraction of major mergers in the early Universe, reviving the debate on whic…
Gaia Early Data Release 3. Modelling and calibration of Gaia's point and line spread functions
Mora, A.; Evans, D. W.; Brown, A. G. A. +18 more
Context. The unprecedented astrometric precision of the Gaia mission relies on accurate estimates of the locations of sources in the Gaia data stream. This is ultimately performed by point spread function (PSF) fitting, which in turn requires an accurate reconstruction of the PSF, including calibrations of all the major dependences. These include …
Bright galaxy sample in the Kilo-Degree Survey Data Release 4. Selection, photometric redshifts, and physical properties
Heymans, C.; Hoekstra, H.; Hildebrandt, H. +16 more
We present a bright galaxy sample with accurate and precise photometric redshifts (photo-zs), selected using ugriZYJHKs photometry from the Kilo-Degree Survey (KiDS) Data Release 4. The highly pure and complete dataset is flux-limited at r < 20 mag, covers ∼1000 deg2, and contains about 1 million galaxies after artifact ma…
The Galaxy Activity, Torus, and Outflow Survey (GATOS). II. Torus and polar dust emission in nearby Seyfert galaxies
Rouan, D.; Rigopoulou, D.; Hunt, L. K. +30 more
We compare high angular resolution mid-infrared (mid-IR) and Atacama Large Millimeter/submillimeter Array (ALMA) far-infrared (far-IR) images of twelve nearby (median 21 Mpc) Seyfert galaxies selected from the Galaxy Activity, Torus, and Outflow Survey (GATOS). The mid-IR unresolved emission contributes more than 60% of the nuclear (diameters of 1…