A $\sim$100 mHz QPO in the X-ray emission from IGR J17361-4441

TL;DR

This paper reports the detection of a 100 mHz quasi-periodic oscillation and a soft thermal component in the X-ray emission of IGR J17361-4441, providing insights into its nature and possible origin.

Contribution

The study presents the first detection of a QPO in IGR J17361-4441 and confirms a soft thermal spectral component, advancing understanding of its accretion processes or tidal disruption event.

Findings

Detection of a ~100 mHz QPO in X-ray emission

Confirmation of a soft thermal component (kT~0.08 keV)

Discussion of the source's nature based on these features

Abstract

IGR J17361-4441 was discovered by INTEGRAL undergoing its first detectable X-ray outburst in 2011 and initially classified as an accreting X-ray binary in the globular cluster NGC 6388. A reanalysis of the outburst data collected with INTEGRAL and Swift suggested that the enhanced X-ray emission from IGR J17361-4441 could have been due to a rare tidal disruption event of a terrestrial- icy planet by a white dwarf. In this letter we report on the analysis of XMM-Newton data collected in 2011 during the outburst from IGR J17361-4441. Our analysis revealed the presence of a $\sim$100 mHz quasi-periodic oscillation in the X-ray emission from the source and confirmed the presence of a soft thermal component (kT$\sim$0.08 keV) in its spectrum. We discuss these findings in the context of the different possibilities proposed to explain the nature of IGR J17361-4441.