6 papers
On the nature of X-ray Flashes
Robert Mochkovitch, Frederic Daigne, Celine Barraud +1
We have developed a toy model for internal shocks which has been used to generate a large number of synthetic GRBs in order to find in the parameter space the conditions which can…
Are X-ray flashes a peculiar class of (soft) gamma-ray bursts ?
Frederic Daigne, Celine Barraud, Robert Mochkovitch
Heise et al. (2001) have reported the identification of a new class of sources by Beppo-SAX, the so-called X-ray flashes (XRFs), which have many common properties with gamma-ray bu…
The youngest massive star clusters in the Magellanic Clouds
M. Heydari-Malayeri, V. Charmandaris, L. Deharveng +3
High resolution observations with HST have recently allowed us to resolve and study several very tight clusters of newly born massive stars in the Magellanic Clouds. Situated in an…
Euler, Hipparcos and the five dwarfs : Reconstructing star formation histories in the Local Group
David Valls-Gabaud, Xavier Hernandez, Gerry Gilmore
The unprecedented quality of recent colour-magnitude diagrams of resolved stellar populations in nearby galaxies requires state-of-the-art techniques to infer the star formation hi…
ROSAC: Studying the clustering properties of X-ray selected AGNs
F. Tesch, F. J. Carrera, D. Engels +6
We present the first ROSAC results of an AGN clustering analysis. This study comprises a sample of 200 AGNs, 75% of which being at low redshifts z<0.5, in the Ursa Major constellat…
The giant luminous arc Statistics. II. spherical lens models based on ROSAT HRI data
Kohji Molikawa, Makoto Hattori, Jean-Paul Kneib +1
We present ROSAT HRI X-ray observations of all the galaxy clusters in the Le Fèvre et al. arc survey sample in order to study the spatial distribution of the intra-cluster medium,…