Letter to the Editor
XMMU J174716.1–281048: a “quasi-persistent” very faint X-ray transient?
Istituto di Astrofisica Spaziale e Fisica Cosmica di Roma – INAF, via del Fosso del Cavaliere 100, 40133 Roma, Italy e-mail: firstname.lastname@example.org
2 Istituto di Astrofisica Spaziale e Fisica Cosmica di Milano – INAF, via E. Bassini 15, 20133 Milano, Italy
3 Universitá di Tor Vergata, Roma, Italy
Accepted: 13 April 2007
The X-ray transient XMMU J174716.1–281048 was serendipitously discovered with XMM-Newton in 2003. It lies about 0.9 degrees off the Galactic Centre and its spectrum shows a high absorption (~ cm-2). Previous X-ray observations of the source field performed in 2000 and 2001 did not detect the source, indicative of a quiescent emission at least two orders of magnitude fainter. The low luminosity during the outburst (~34 erg s-1 at 8 kpc) indicates that the source is a member of the “very faint X-ray transients” class. On 2005 March 22nd the INTEGRAL satellite caught a possible type-I X-ray burst from the new INTEGRAL source IGR J17464–2811, classified as fast X-ray transient. This source was soon found to be positionally coincident, within the uncertainties, with XMMU J174716.1–281048. Here we report data analysis of the X-ray burst observed with the IBIS and JEM-X telescopes and confirm the type-I burst nature. We also re-analysed XMM-Newton and Chandra archival observations of the source field. We discuss the implications of these new findings, particularly related to the source distance as well as the source classification.
Key words: Galaxy: center / X-rays: binaries / stars: neutron / X-rays: bursts / X-ray: individuals: XMMU J174716.1–281048
© ESO, 2007