XMM-Newton observed the X-ray binary pulsar XTE J0103-728 in outburst
ATel #1095; F. Haberl (MPE), W. Pietsch (MPE), P. Kahabka (MPE)
on 1 Jun 2007; 15:46 UT
Credential Certification: Frank Haberl (fwh@mpe.mpg.de)
Subjects: X-ray, Binary, Neutron Star, Transient, Pulsar
During an XMM-Newton observation on 2006, Oct. 2 of a field in the Small Magellanic Cloud a bright X-ray transient was observed. Timing analysis revealed X-ray pulsations with a period of 6.85 s which identifies the source, designated XMMU J010253.1-724433 with XTE J0103-728 = SXP6.85. The X-ray spectrum is well represented by a powerlaw with photon index 0.45 +/- 0.03 and an additional soft component. The derived X-ray luminosity (0.2-10.0 keV) was 1.7x10^37 erg/s. The improved X-ray position of R.A.(J2000) = 01:02:53.1 Dec.(J2000) = -72:44:33 (2 arcsec systematic error) is consistent with the position of object 54787 in the UBVR CCD Survey of the Magellanic Clouds by Massey (2002, ApJS, 141, 81). Optical brightness (V = 14.59 mag) and colors are consistent with a Be star, confirming the Be/X-ray binary pulsar nature of XTE J0103-728.