Discovery of X-ray Pulsations from the HMXB Source AXJ1749.1-2733

TL;DR

This paper reports the discovery of X-ray pulsations from the high mass X-ray binary AX J1749.1-2733, identifying it as a new transient X-ray pulsar with a ~132 s period and heavily absorbed spectrum.

Contribution

The paper presents the first detection of X-ray pulsations from AX J1749.1-2733, establishing it as a new transient high mass X-ray binary pulsar.

Findings

Detected X-ray pulsations at ~132 s period.

Observed double-peaked pulse profile with 25-30% pulse fraction.

Identified heavy intrinsic absorption in the source spectrum.

Abstract

We are reporting a discovery of X-ray pulsations from the source AX J1749.1-2733 with the period of ~132 s based on the XMM-Newton data obtained in March 2007. The observed pulse profile has a double-peaked structure with the pulse fraction of about 25-30 % 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 Sept. 9, 2003 in the 20-50 keV energy band. Due to the double-peaked pulse profile, there is an additional peak on both periodograms of nearly ~66 s, 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 ($N_H\simeq2\times10^{23}$ cm$^{-2}$) due to a strong intrinsic absorption in the binary system that leads to the conclusion that AX J1749.1-2733 is a new transient X-ray pulsar in the high mass X-ray binary system.