IGR J17451-3022: a dipping and eclipsing low mass X-ray binary

TL;DR

This study analyzes X-ray data from multiple observatories to characterize the outburst, spectral features, and orbital period of the dipping and eclipsing low mass X-ray binary IGR J17451-3022, revealing a thermal accretion disk and ionized absorber.

Contribution

First detailed multi-instrument analysis of IGR J17451-3022's outburst, identifying eclipses, dips, and estimating its orbital period.

Findings

Source remained soft during the outburst.

Detected partial and rectangular X-ray eclipses.

Estimated orbital period at approximately 6.3 hours.

Abstract

In this paper, we report on the available X-ray data collected by INTEGRAL, Swift, and XMM-Newton during the first outburst of the INTEGRAL transient IGR J17451-3022, discovered in 2014 August. The monitoring observations provided by the JEM-X instruments on-board INTEGRAL and the Swift/XRT showed that the event lasted for about 9 months and that the emission of the source remained soft for the entire period. The source emission is dominated by a thermal component (kT~1.2 keV), most likely produced by an accretion disk. The XMM-Newton observation carried out during the outburst revealed the presence of multiple absorption features in the soft X-ray emission that could be associated to the presence of an ionized absorber lying above the accretion disk, as observed in many high-inclination low mass X-ray binaries. The XMM-Newton data also revealed the presence of partial and rectangular X-ray eclipses (lasting about 820 s), together with dips. The latter can be associated with increases in the overall absorption column density in the direction of the source. The detection of two consecutive X-ray eclipses in the XMM-Newton data allowed us to estimate the source orbital period at 22620.5(-1.8,+2.0) s (1{\sigma} c.l.).