Discovery of X-ray pulsations from the HMXB source AXJ1749.1-2733

Abstract

We are reporting the discovery of X-ray pulsations from the source AXJ1749.1-2733 with the period of ~132 s based on the XMM-Newton data obtained in 2007 March. The observed pulse profile has a double-peaked structure with the pulse fraction of about 25-30 per cent in the 3-10 keV energy band. We have also found that a periodicity with practically the same period has been detected from the source by the IBIS telescope onboard the INTEGRAL observatory during an outburst on 2003 September 9 in the 20-50 keV energy band. Due to the double-peaked pulse profile, there is an additional peak on both periodograms of ~66s therefore we have also investigated the possibility that the last value is the true pulse period. The source spectrum obtained by the XMM-Newton observatory in the soft energy band is being heavily absorbed (N_H ~= 2 × 10²³cm^-2) due to a strong intrinsic absorption in the binary system that leads to the conclusion that AXJ1749.1-2733 is a new transient X-ray pulsar in the high-mass X-ray binary system.