Search Publications
Neutral gas properties of Lyman continuum emitting galaxies: Column densities and covering fractions from UV absorption lines
Rigby, J. R.; Chisholm, J.; Schaerer, D. +3 more
Context. The processes allowing the escape of ionizing photons from galaxies into the intergalactic medium are poorly known.
Aims: To understand how Lyman continuum (LyC) photons escape galaxies, we constrain the H I covering fractions and column densities using ultraviolet (UV) H I and metal absorption lines of 18 star-forming galaxies that …
TOPoS. IV. Chemical abundances from high-resolution observations of seven extremely metal-poor stars
Steffen, M.; Ludwig, H. -G.; Bonifacio, P. +15 more
Context. Extremely metal-poor (EMP) stars provide us with indirect information on the first generations of massive stars. The TOPoS survey has been designed to increase the census of these stars and to provide a chemical inventory that is as detailed as possible.
Aims: Seven of the most iron-poor stars have been observed with the UVES spectro…
A Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE). II. Constraining the quenching time in the stripped galaxy NGC 4330
Ferrarese, L.; Buat, V.; Boquien, M. +24 more
The Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE) is a blind narrow-band Hα + [NII] imaging survey carried out with MegaCam at the Canada-France-Hawaii Telescope. During pilot observations taken in the spring of 2016 we observed NGC 4330, an intermediate mass (M* ≃ 109.8 M⊙) edge-on star forming…
Solar total and spectral irradiance reconstruction over the last 9000 years
Solanki, S. K.; Wu, C. -J.; Krivova, N. A. +1 more
Context. Changes in solar irradiance and in its spectral distribution are among the main natural drivers of the climate on Earth. However, irradiance measurements are only available for less than four decades, while assessment of solar influence on Earth requires much longer records.
Aims: The aim of this work is to provide the most up-to-dat…
Dissecting stellar chemical abundance space with t-SNE
Guiglion, G.; Anders, F.; Chiappini, C. +4 more
In the era of large-scale Galactic astronomy and multi-object spectroscopic stellar surveys, the sample sizes and the number of available stellar chemical abundances have reached dimensions in which it has become difficult to process all the available information in an effective manner. In this paper we demonstrate the use of a dimensionality-redu…
The XMM Cluster Outskirts Project (X-COP): Thermodynamic properties of the intracluster medium out to R200 in Abell 2319
Hurier, G.; Pointecouteau, E.; Molendi, S. +5 more
Aims: We present the joint analysis of the X-ray and Sunyaev-Zel'dovich (SZ) signals in Abell 2319, the galaxy cluster with the highest signal-to-noise ratio in SZ Planck maps and that has been surveyed within our XMM-Newton Cluster Outskirts Project (X-COP), a very large program which aims to grasp the physical condition in 12 local (z < …
Empirical photometric calibration of the Gaia red clump: Colours, effective temperature, and absolute magnitude
Arenou, F.; Babusiaux, C.; Turon, C. +2 more
Context. Gaia Data Release 1 allows the recalibration of standard candles such as the red clump stars. To use those stars, they first need to be accurately characterised. In particular, colours are needed to derive interstellar extinction. As no filter is available for the first Gaia data release and to avoid the atmosphere model mismatch, an empi…
GALACTICNUCLEUS: A high angular resolution JHKs imaging survey of the Galactic centre. I. Methodology, performance, and near-infrared extinction towards the Galactic centre
Nishiyama, S.; Hilker, M.; de Zeeuw, P. T. +9 more
Context. The Galactic centre (GC) is of fundamental astrophysical interest, but existing near-infrared surveys fall short covering it adequately, either in terms of angular resolution, multi-wavelength coverage, or both. Here we introduce the GALACTICNUCLEUS survey, a JHKs imaging survey of the centre of the Milky Way with a 0.2″
A comparison of the local spiral structure from Gaia DR2 and VLBI maser parallaxes
Menten, K. M.; Xu, Y.; Zhang, B. +8 more
Context. The Gaia mission has released the second data set (Gaia DR2), which contains parallaxes and proper motions for a large number of massive, young stars.
Aims: We investigate the spiral structure in the solar neighborhood revealed by Gaia DR2 and compare it with that depicted by VLBI maser parallaxes.
Methods: We examined three sam…
Puzzling Lyman-alpha line profiles in green pea galaxies
Schaerer, D.; Scarlata, C.; Oey, M. S. +4 more
Context. The Lyman-alpha (Lyα) line of hydrogen is of prime importance for detecting galaxies at high redshift. For a correct data interpretation, numerical radiative transfer models are necessary due to Lyα resonant scattering off neutral hydrogen atoms.
Aims: Recent observations have discovered an escape of ionizing Lyman-continuum radiatio…