135 citations · 984 across the 46 of their papers we have counts for
5 papers · 1 filter
Evolution of the Phase-Space Density of Dark Matter Halos and Mixing Effects in Merger Events
Sébastien Peirani, Fabrice Durier, José Antonio De Freitas Pacheco
Cosmological N-body simulations were performed to study the evolution of the phase-space density Q = rho/sigma^3 of dark matter halos. No significant differences in the scale relat…
Mass Determination of Groups of Galaxies: Effects of the Cosmological Constant
Sébastien Peirani, José Antonio De Freitas Pacheco
The spherical infall model first developed by Lemaître and Tolman was modified in order to include the effects of a dark energy term. The resulting velocity-distance relation was e…
New insights on the complex planetary nebula Hen 2-113
Eric Lagadec, Olivier Chesneau, Mikako Matsuura +5
We report infrared observations of the planetary nebula Hen 2-113 obtained with VLT/NACO, VLTI/MIDI, VLT/ISAAC and TIMMI at the ESO 3.6m. Hen 2-113 exhibits a clear ring-like struc…
Indirect Search for Dark Matter
José Antonio De Freitas Pacheco, Sébastien Peirani
Possible dark matter candidates are reviewed as well as indirect search methods based on annihilation or decay channels of these particles. Neutralino is presently the best particl…
A Search for Very Active Stars in the Galaxy
G. Tsarevsky, J. A. De Freitas Pacheco, N. Kardashev +7
We report the first results of a systematic search near the plane of the Galaxy for the so called very active stars (VAS), which are characterized by a hard X-ray spectrum and acti…