Free Access
Volume 495, Number 3, March I 2009
Page(s) 733 - 741
Section Extragalactic astronomy
Published online 30 January 2009

Online Material

Appendix A

In this section we give positional and spectral information on all 335 point source detections in five archival XMM-Newton observations of the disc of M 31. Table A.1 gives the source numbers in order of RA and the positions as returned by the source detection routines (i.e. no astrometric corrections were applied). We also provide details of which camera the source spectra or counts are taken from and details of the best fit spectral model for each source, including the absorption ($n_{\rm H}$), best fit photon index ($\Gamma $) or temperature (kT) depending on which model, and the luminosity derived from that fit. The symbol f signifies that the absorption was fixed to $0.1 \times 10^{22}$ H atom cm-2 for that source. Note that several of the faint sources display a very large formal uncertainty in $n_{\rm H}$. The actualy best fit values were accepted only if they exceeded the Galactic foreground value ( $n_{\rm H} = 0.1 \times 10^{22}$ H atom cm-2). Errors on the absorption and $\Gamma $/kT are the two sided, non-symmetric errors derived by xspec. The luminosity given is the mean value of the 90% confidence interval and hence has symetric errors quoted in brackets. Best fit values are given for all sources with more than 50 source counts; even for cases where the fit implies significant or very large error bars. Sources with less than 50 source counts are denoted with ``faint'' as their best fit model, these sources are then summed by field and the parameters of the best fit power law to the summed spectrum applied to each source. Hence for the faint sources no absorption or $\Gamma $/kT are given. Finally we give a classification for each source. These are the classifications and source number from Pietsch et al. (2005) where the sources appear in that work. For the 34 sources not in Pietsch et al. (2005) as well as source 238 we give our own classifications and each of these have a 1 next to it.

Table A.1:   Position and spectral properties of each source detected in five archival XMM-Newton observations of the disc of M 31. We give the detected source position and detection camera(s) for each source. The best fit model to a source can be faint (less than 50 source counts), pl (power law), bb (blackbody), br (bremsstrahlung), nsa (neutron star atmosphere) or diskbb (disk blackbody). Unless a source is faint we then give the absorption ($n_{\rm H}$) and appropriate parameter (photon index, $\Gamma $, or temperature, kT) of the best fit model. The symbol f signifies that the absorption was fixed to $0.1 \times 10^{22}$ H atom cm-2 for that source. For all sources we then quote the luminosity for that source derived from the model parameters with 90% confidence errors in brackets, and finally a classification, either from Pietsch et al. (2005) with the source number, or this work (denoted with a1).

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