Publications (10)
Young stars discovered in dwarf spheroidal galaxies confirm their recent infall into the Milky way
Francois Hammer, Piercarlo Bonifacio, Elisabetta Caffau +10
Recent observations from the ESA Gaia satellite and with the ESO VLT, have identified the presence of a population of young, 0.5 to 2 Gyr old, stars in the halo and in dwarf sphero…
Revisiting Hipparcos data for pre-main sequence stars
Claude Bertout, Noel Robichon, Frederic Arenou
We cross-correlate the Herbig & Bell and Hipparcos Catalogues in order to extract the results for young stellar objects (YSOs). We compare the distances of individual young stars a…
SPADES: Stellar Parameters Determination Software
Helene Posbic, David Katz, Elisabetta Caffau +4
Context. As increasingly more spectroscopic data are being delivered by medium- and high-resolving power multi-object spectrographs, more automatic stellar parameter determination…
Most dwarf spheroidal galaxies surrounding the Milky Way cannot be dark-matter dominated satellites
Francois Hammer, Yanbin Yang, Frederic Arenou +5
Milky Way dwarf spheroidal galaxies are the tiniest observed galaxies and are currently associated with the largest fractions of dark matter, which is revealed by their too large v…
Astrometric and Light-travel Time Orbits to Detect Low-mass Companions: A Case Study of the Eclipsing System R Canis Majoris
Ignasi Ribas, Frederic Arenou, Edward F. Guinan
We discuss a method to determine orbital properties and masses of low-mass bodies orbiting eclipsing binaries. The analysis combines long-term eclipse timing modulations (light-tra…
Orbital evidences for dark-matter-free Milky Way dwarf spheroidal galaxies
Francois Hammer, Yanbin Yang, Frederic Arenou +4
The nature of Milky Way dwarf spheroidals (MW dSphs) has been questioned, in particular whether they are dominated by dark matter (DM). Here we investigate an alternative scenario,…