@article {23880, title = {The XMM-Newton survey of the Small Magellanic Cloud: discovery of the 11.866 s Be/X-ray binary pulsar XMMU J004814.0-732204(SXP11.87)}, volume = {527}, year = {2011}, month = {2011/03/1}, pages = {A131}, abstract = {
Aims: One of the goals of the XMM-Newton survey of the Small Magellanic Cloud is to study the Be/X-ray binary population. During one of our first survey observations, a bright new transient - XMMU J004814.0-732204 - was discovered.
Methods: We present the analysis of the EPIC X-ray data, together with optical observations, to investigate the spectral and temporal characteristics of XMMU J004814.0-732204.
Results: We found coherent X-ray pulsations in the EPIC data with a period of (11.86642 {\textpm} 0.00017) s. The X-ray spectrum can be modelled by an absorbed power law with an indication for a soft excess. Depending on the modelling of the soft X-ray spectrum, the photon index ranges between 0.53 and 0.66. We identify the optical counterpart as a B = 14.9 mag star that was monitored during the MACHO and OGLE-III projects. The optical light curves show regular outbursts by ~0.5 mag in B and R and up to 0.9 mag in I, which repeat on a time scale of about 1000 days. The OGLE-III optical colours of the star are consistent with an early B spectral type. An optical spectrum obtained at the 1.9 m telescope of the South African Astronomical Observatory in December 2009 shows Hα emission with an equivalent width of 3.5 {\textpm} 0.6 {\r A}.
Conclusions: The X-ray spectrum and the detection of pulsations suggest that XMMU J004814.0-732204is a new high-mass X-ray binary pulsar in the SMC. The long term variability and the Hα emission line in the spectrum of the optical counterpart identify it as a Be/X-ray binary system.}, keywords = {Astrophysics - High Energy Astrophysical Phenomena, Be, galaxies: individual: Small Magellanic Cloud, galaxies: stellar content, stars: emission-line, stars: neutron, X-rays: binaries}, isbn = {0004-6361}, url = {https://ui.adsabs.harvard.edu/abs/2011A\&A...527A.131S}, author = {Sturm, R. and Haberl, F. and Coe, M. J. and Bartlett, E. S. and Buckley, D. A. H. and Corbet, R. H. D. and Ehle, M. and Filipovi{\'c}, M. D. and Hatzidimitriou, D. and Mereghetti, S. and La Palombara, N. and Pietsch, W. and Tiengo, A. and Townsend, L. J. and Udalski, A.} }