Search Publications
J-PLUS: Identification of low-metallicity stars with artificial neural networks using SPHINX
Caballero, J. A.; Mendes de Oliveira, C.; Beers, T. C. +24 more
Context. We present a new methodology for the estimation of stellar atmospheric parameters from narrow- and intermediate-band photometry of the Javalambre Photometric Local Universe Survey (J-PLUS), and propose a method for target pre-selection of low-metallicity stars for follow-up spectroscopic studies. Photometric metallicity estimates for star…
The VANDELS survey: the role of ISM and galaxy physical properties in the escape of Lyα emission in z ∼ 3.5 star-forming galaxies
Maccagni, D.; Schaerer, D.; Finkelstein, S. L. +21 more
Aims: We wish to investigate the physical properties of a sample of Lyα emitting galaxies in the VANDELS survey, with particular focus on the role of kinematics and neutral hydrogen column density in the escape and spatial distribution of Lyα photons.
Methods: From all the Lyα emitting galaxies in the VANDELS Data Release 2 at 3.5 ≲ z ≲ …
The Hubble PanCET program: an extensive search for metallic ions in the exosphere of GJ 436 b
Sanz-Forcada, J.; Ehrenreich, D.; Lecavelier des Etangs, A. +15 more
Context. The quiet M2.5 star GJ 436 hosts a warm Neptune that displays an extended atmosphere that dwarfs its own host star. Predictions of atmospheric escape in such planets state that H atoms escape from the upper atmosphere in a collisional regime and that the flow can drag heavier atoms to the upper atmosphere. It is unclear, however, what ast…
Plasmoid-mediated reconnection in solar UV bursts
Peter, H.; Chitta, L. P.; Young, P. R. +1 more
Context. Ultraviolet bursts are transients in the solar atmosphere with an increased impulsive emission in the extreme UV lasting for one to several tens of minutes. They often show spectral profiles indicative of a bi-directional outflow in response to magnetic reconnection.
Aims: To understand UV bursts, we study how motions of magnetic ele…
X-shooter spectroscopy of young stars with disks. The TW Hydrae association as a probe of the final stages of disk accretion
Alcalá, J. M.; Randich, S.; Scholz, A. +9 more
Context. Measurements of the fraction of disk-bearing stars in clusters as a function of age indicate protoplanetary disk lifetimes ≲10 Myr. However, our knowledge of the time evolution of mass accretion in young stars over the disk lifespans is subject to many uncertainties, especially at the lowest stellar masses (M⋆).
Aims: We i…
J-PLUS: photometric calibration of large-area multi-filter surveys with stellar and white dwarf loci
Hernández-Monteagudo, C.; Carrasco, J. M.; Tremblay, P. -E. +24 more
Aims: We present the photometric calibration of the 12 optical passbands observed by the Javalambre Photometric Local Universe Survey (J-PLUS).
Methods: The proposed calibration method has four steps: (i) definition of a high-quality set of calibration stars using Gaia information and available 3D dust maps; (ii) anchoring of the J-PLUS …
Census of ρ Ophiuchi candidate members from Gaia Data Release 2
Mora, A.; Cánovas, H.; Bombrun, A. +6 more
Context. The Ophiuchus cloud complex is one of the best laboratories to study the earlier stages of the stellar and protoplanetary disc evolution. The wealth of accurate astrometric measurements contained in the Gaia Data Release 2 can be used to update the census of Ophiuchus member candidates.
Aims: We seek to find potential new members of …
Evolved massive stars at low-metallicity. I. A source catalog for the Small Magellanic Cloud
Yang, Ming; Bonanos, Alceste Z.; Jiang, Bi-Wei +9 more
We present a clean, magnitude-limited (IRAC1 or WISE1 ≤ 15.0 mag) multiwavelength source catalog for the Small Magellanic Cloud (SMC) with 45 466 targets in total, with the purpose of building an anchor for future studies, especially for the massive star populations at low-metallicity. The catalog contains data in 50 different bands including 21 o…
Distances to molecular clouds at high galactic latitudes based on Gaia DR2
Macquart, Jean-Pierre; Xu, Ye; Yan, Qing-Zeng +4 more
We report the distances of molecular clouds at high Galactic latitudes (|b| > 10°) derived from parallax and G-band extinction (AG) measurements in the second Gaia data release, Gaia DR2. Aided by Bayesian analyses, we determined distances by identifying the breakpoint in the extinction AG toward molecular clouds and using…
Probing fragmentation and velocity sub-structure in the massive NGC 6334 filament with ALMA
André, Ph.; Arzoumanian, D.; Shimajiri, Y. +3 more
Context. Herschel imaging surveys of galactic interstellar clouds support a paradigm for low-mass star formation in which dense molecular filaments play a crucial role. The detailed fragmentation properties of star-forming filaments remain poorly understood, however, and the validity of the filament paradigm in the intermediate- to high-mass regim…