X-ray monitoring of classical novae in the central region of M 31 III. Autumn and winter 2009/10, 2010/11, and 2011/12

摘要: Context. Classical novae (CNe) represent the major class of supersoft X-ray sources (SSSs) in central region our neighbouring galaxy M 31. Aims. We performed a dedicated monitoring 31 region, which aimed to detect SSS counterparts CNe, with XMM-Newton and Chandra between Nov. Mar. years 2009/10, 2010/11, 2011/12. Methods. systematically searched data for CNe determined their light curves also spectral properties case data. Additionally, we luminosity upper limits all previously known emitting novae, are not detected anymore, field view recent optical outbursts. Results. In total, 24 X-rays. Seven these were from previous observations, including nova longest phase, M31N 1996-08b, was found fade below detection limit 13.8 yr after outburst. Of new discoveries, several exhibit significant variability short-term one object showing suspected period about 1.3 h. studied state most outburst recurrent nova, had shown shortest time ever observed two outbursts (∼5 yr). The total number counterpart increased 79, subjected this extended catalogue detailed statistical studies. Four indicated correlations parameters could be confirmed improved. Furthermore, indications that multi-dimensional parameter space might dominated by single physical parameter, provide interpretations suggest implications. various outliers established discuss evidence different behaviour bulge disk. Conclusions. Exploration multi-wavelength measurements is powerful tool examining extragalactic populations. While there hints stellar populations (bulge vs. disk) produce dissimilar outbursts, growing overall an average understood surprisingly simple terms.