Search Publications
High-resolution confirmation of an extended helium atmosphere around WASP-107b
Aceituno, J.; Ehrenreich, D.; Lovis, C. +7 more
Context. Probing the evaporation of exoplanet atmospheres is key to understanding the formation and evolution of exoplanetary systems. The main tracer of evaporation in the UV is the Lyman-α transition, which can reveal extended exospheres of neutral hydrogen. Recently, the near-infrared (NIR) metastable helium triplet (10 833 Å) revealed extended…
Testing massive star evolution, star formation history, and feedback at low metallicity. Spectroscopic analysis of OB stars in the SMC Wing
Hamann, W. -R.; Gallagher, J. S.; Oskinova, L. M. +6 more
Stars that start their lives with spectral types O and early B are the progenitors of core-collapse supernovae, long gamma-ray bursts, neutron stars, and black holes. These massive stars are the primary sources of stellar feedback in star-forming galaxies. At low metallicities, the properties of massive stars and their evolution are not yet fully …
Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS). II. A broadened sodium feature on the ultra-hot giant WASP-76b
Heng, K.; Ségransan, D.; Deline, A. +18 more
High-resolution optical spectroscopy is a powerful tool to characterise exoplanetary atmospheres from the ground. The sodium D lines, with their large cross sections, are especially suited to studying the upper layers of atmospheres in this context. We report on the results from Hot Exoplanet Atmosphere Resolved with Transit Spectroscopy survey (H…
Gaia Data Release 2. Cross-match with external catalogues: algorithms and results
Marinoni, S.; Marrese, P. M.; Altavilla, G. +1 more
Context. Although the Gaia catalogue on its own is a very powerful tool, it is the combination of this high-accuracy archive with other archives that will truly open up amazing possibilities for astronomical research. The advanced interoperation of archives is based on cross-matching, leaving the user with the feeling of working with one single da…
Hunting for open clusters in Gaia DR2: the Galactic anticentre
Castro-Ginard, A.; Jordi, C.; Luri, X. +2 more
Context. The Gaia Data Release 2 (DR2) provided an unprecedented volume of precise astrometric and excellent photometric data. In terms of data mining the Gaia catalogue, machine learning methods have shown to be a powerful tool, for instance in the search for unknown stellar structures. Particularly, supervised and unsupervised learning methods c…
He I λ 10 830 Å in the transmission spectrum of HD209458 b
Schmitt, J. H. M. M.; Alonso-Floriano, F. J.; Sánchez-López, A. +27 more
Context. Recently, the He I triplet at 10 830 Å was rediscovered as an excellent probe of the extended and possibly evaporating atmospheres of close-in transiting planets. This has already resulted in detections of this triplet in the atmospheres of a handful of planets, both from space and from the ground. However, while a strong signal is expect…
Old and young stellar populations in DustPedia galaxies and their role in dust heating
Bianchi, S.; Fritz, J.; Madden, S. C. +19 more
Aims: Within the framework of the DustPedia project we investigate the properties of cosmic dust and its interaction with stellar radiation (originating from different stellar populations) for 814 galaxies in the nearby Universe, all observed by the Herschel Space Observatory.
Methods: We take advantage of the widely used fitting code CI…
Reclassification of Cepheids in the Gaia Data Release 2. Period-luminosity and period-Wesenheit relations in the Gaia passbands
Ripepi, V.; Molinaro, R.; Eyer, L. +3 more
Context. Classical Cepheids are the most important primary indicators for the extragalactic distance scale. Establishing the precise zero points of their period-luminosity and period-Wesenheit (PL/PW) relations has profound consequences on the estimate of H0. Type II Cepheids are also important distance indicators and tracers of old ste…
The Galactic WC and WO stars. The impact of revised distances from Gaia DR2 and their role as massive black hole progenitors
Hamann, W. -R.; Oskinova, L. M.; Sander, A. A. C. +4 more
Wolf-Rayet stars of the carbon sequence (WC stars) are an important cornerstone in the late evolution of massive stars before their core collapse. As core-helium burning, hydrogen-free objects with huge mass-loss, they are likely the last observable stage before collapse and thus promising progenitor candidates for type Ib/c supernovae. Their stro…
PHIBSS2: survey design and z = 0.5 - 0.8 results. Molecular gas reservoirs during the winding-down of star formation
Lutz, D.; Wuyts, S.; Förster Schreiber, N. M. +29 more
Following the success of the Plateau de Bure high-z Blue Sequence Survey (PHIBSS), we present the PHIBSS2 legacy program, a survey of the molecular gas properties of star-forming galaxies on and around the star-formation main sequence (MS) at different redshifts using IRAM's NOrthern Extended Millimeter Array (NOEMA). This survey significantly ext…