218 articles – 617 references  [version française]
HAL: in2p3-00013803, version 1

Detailed view  Export this paper
Astronomy and Astrophysics 405 (2003) 851-857
Microlensing towards M31 with MDM data
S. Calchi Novati, P. Jetzer, G. Scarpetta, Y. Giraud-Heraud1, J. Kaplan1, S. Paulin-Henriksson1, A. Gould

We report the final analysis of a search for microlensing events in the direction of the Andromeda galaxy, which aimed to probe the MACHO composition of the M31 halo using data collected during the 1998-99 observational campaign at the MDM observatory. In a previous paper, we discussed the results from a first set of observations. Here, we deal with the complete data set, and we take advantage of some INT observations in the 1999-2000 seasons. This merging of data sets taken by different instruments turns out to be very useful, the study of the longer baseline available allowing us to test the uniqueness characteristic of microlensing events. As a result, all the candidate microlensing events previously reported turn out to be variable stars. We further discuss a selection based on different criteria, aimed at the detection of short--duration events. We find three candidates whose positions are consistent with self--lensing events, although the available data do not allow us to conclude unambiguously that they are due to microlensing.
1:  PCC - Physique Corpusculaire et Cosmologie - Collège de France
Physics/Astrophysics/Cosmology and Extra-Galactic Astrophysics

Sciences of the Universe/Astrophysics
Fulltext link: