Search Publications
Ages of the Bulge Globular Clusters NGC 6522 and NGC 6626 (M28) from HST Proper-motion-cleaned Color-Magnitude Diagrams
Vieira, R. G.; Bica, E.; Nardiello, D. +5 more
Bulge globular clusters (GCs) with metallicities [Fe/H] ≲ -1.0 and blue horizontal branches are candidates to harbor the oldest populations in the Galaxy. Based on the analysis of HST proper-motion-cleaned color-magnitude diagrams in filters F435W and F625W, we determine physical parameters for the old bulge GCs NGC 6522 and NGC 6626 (M28), both w…
The Anatomy of the Column Density Probability Distribution Function (N-PDF)
Goodman, Alyssa; Burkhart, Blakesley; Chen, Hope How-Huan +1 more
The column density probability distribution function (N-PDF) of Giant Molecular Clouds (GMCs) has been used as a diagnostic of star formation. Simulations and analytic predictions have suggested that the N-PDF is composed of a low-density lognormal component and a high-density power-law component tracing turbulence and gravitational collapse, resp…
The Gaia-ESO Survey: evidence of atomic diffusion in M67?
Gilmore, G.; Bayo, A.; Salaris, M. +37 more
Investigating the chemical homogeneity of stars born from the same molecular cloud at virtually the same time is very important for our understanding of the chemical enrichment of the interstellar medium and with it the chemical evolution of the Galaxy. One major cause of inhomogeneities in the abundances of open clusters is stellar evolution of t…
MarsSI: Martian surface data processing information system
Poulet, F.; Quantin-Nataf, C.; Leyrat, C. +10 more
MarsSI (Acronym for Mars System of Information, https://emars.univ-lyon1.fr/MarsSI/, is a web Geographic Information System application which helps managing and processing martian orbital data. The MarsSI facility is part of the web portal called PSUP (Planetary SUrface Portal) developed by the Observatories of Paris Sud (OSUPS) and Lyon (OSUL) to…
The chemistry of disks around T Tauri and Herbig Ae/Be stars
Agúndez, Marcelino; Le Petit, Franck; Roueff, Evelyne +1 more
Context. Infrared and (sub-)millimeter observations of disks around T Tauri and Herbig Ae/Be stars point to a chemical differentiation, with a lower detection rate of molecules in disks around hotter stars.
Aims: We aim to investigate the underlying causes of the chemical differentiation indicated by observations and perform a comparative stu…
A Large Moving Group within the Lower Centaurus Crux Association
Henning, Thomas; Goldman, Bertrand; Röser, Siegfried +2 more
Scorpius-Centaurus is the nearest OB association, and its hundreds of members are divided into subgroups, including the Lower Centaurus Crux (LCC). Here we study the dynamics of the LCC area. We report the revelation of a large moving group containing more than 1800 intermediate- and low-mass young stellar objects and brown dwarfs that escaped ide…
First detection of H2S in a protoplanetary disk. The dense GG Tauri A ring
Beck, T.; Chapillon, E.; Wakelam, V. +8 more
Context. Studying molecular species in protoplanetary disks is very useful to characterize the properties of these objects, which are the site of planet formation.
Aims: We attempt to constrain the chemistry of S-bearing molecules in the cold parts of circumstellar disk of GG Tau A.
Methods: We searched for H2S, CS, SO, and SO…
Magnetic Flux Cancelation as the Buildup and Trigger Mechanism for CME-producing Eruptions in Two Small Active Regions
Panesar, Navdeep K.; Moore, Ronald L.; Sterling, Alphonse C.
We follow two small, magnetically isolated coronal mass ejection (CME)-producing solar active regions (ARs) from the time of their emergence until several days later, when their core regions erupt to produce the CMEs. In both cases, magnetograms show: (a) following an initial period where the poles of the emerging regions separate from each other,…
Improved distances and ages for stars common to TGAS and RAVE
Grebel, Eva K.; Steinmetz, Matthias; Bland-Hawthorn, Joss +15 more
We combine parallaxes from the first Gaia data release with the spectrophotometric distance estimation framework for stars in the fifth RAVE survey data release. The combined distance estimates are more accurate than either determination in isolation - uncertainties are on average two times smaller than for RAVE-only distances (three times smaller…
Combining low- to high-resolution transit spectroscopy of HD 189733b. Linking the troposphere and the thermosphere of a hot gas giant
Piotto, Giampaolo; Pepe, Francesco; Heng, Kevin +8 more
Space-borne low- to medium-resolution (ℛ 102-103) and ground-based high-resolution spectrographs (ℛ 105) are commonly used to obtain optical and near infrared transmission spectra of exoplanetary atmospheres. In this wavelength range, space-borne observations detect the broadest spectral features (alkali doublets, …