Detection of an orbital period in the supergiant high mass X-ray binary IGR J16465$-$4507 with Swift-BAT

TL;DR

This study detects an orbital period of approximately 30.24 days in the supergiant high mass X-ray binary IGR J16465-4507 using Swift-BAT data, revealing insights into its accretion behavior and orbital characteristics.

Contribution

First detection of the orbital period in IGR J16465-4507 through long-term Swift-BAT survey data analysis.

Findings

Orbital period of 30.243 days identified.

The system is likely wind-fed with a homogeneous wind.

The source is not a Supergiant Fast X-ray Transient.

Abstract

We analysed the IGR J16465-4507 Burst Alert Teelescope survey data collected during the first 54 months of the Swift mission. The source is in a crowded field and it is revealed through an ad hoc imaging analysis at a significance level of ~14 standard deviations. The 15-50 keV average flux is ~3E-11 erg/cm^2/s. The timing analysis reveals an orbital period of 30.243 +/- 0.035 days. The folded light curve shows the presence of a wide phase interval of minimum intensity, lasting ~20% of the orbital period. This could be explained with a full eclipse of the compact object in an extremely eccentric orbit or with the passage of the compact source through a lower density wind at the orbit apastron. The modest dynamical range observed during the BAT monitoring suggests that IGR J16465-4507 is a wind-fed system, continuously accreting from a rather homogeneous wind, and not a member of the Supergiant Fast X-ray Transient class.