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Variable stars towards the bulge of M31: the AGAPE catalogue

R. Ansari·M. Auriere·P. Baillon·A. Bouquet·G. Coupinot·Ch. Coutures·C. Ghesquiere·Y. Giraud-Heraud·D. Gillieron·P. Gondolo·J. Hecquet·J. Kaplan·A. Kim·Y. Le Du·A. L. Melchior·M. Moniez·J. P. Picat·G. Soucail
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Abstract

We present the AGAPE astrometric and photometric catalogue of 1579 variable stars in a 14'x10' field centred on M31. This work is the first survey devoted to variable stars in the bulge of M31. The R magnitudes of the objects and the B-R colours suggest that our sample is dominated by red long-period variable stars (LPV), with a possible overlap with Cepheid-like type II stars. Twelve nova candidates are identified. Correlations with other catalogues suggest that 2 novae could be recurrent novae and provide possible optical counterparts for 2 supersoft X-ray sources candidates observed with Chandra.

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R. Ansari, M. Auriere, P. Baillon, A. Bouquet, G. Coupinot, Ch. Coutures, C. Ghesquiere, Y. Giraud-Heraud, D. Gillieron, P. Gondolo, J. Hecquet, J. Kaplan, A. Kim, Y. Le Du, A. L. Melchior, M. Moniez, J. P. Picat, G. Soucail. 2004-05-20. Variable stars towards the bulge of M31: the AGAPE catalogue. https://doi.org/10.1051/0004-6361%3A20035659

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