High energy X-ray emission from recurrent novae in quiescence: T CrB

TL;DR

This study reports Suzaku X-ray observations of the recurrent nova T CrB in quiescence, highlighting its first detection in the hard-X-ray band and providing insights into the accretion processes around the white dwarf.

Contribution

It is the first to detect hard-X-ray emission from a recurrent nova during quiescence, revealing boundary layer characteristics through spectral and variability analysis.

Findings

Detection of hard X-ray emission at ~40 keV from T CrB in quiescence

X-ray spectrum consistent with cooling-flow emission from boundary layer

Presence of stochastic flux variations indicating boundary layer origin

Abstract

We present Suzaku X-ray observations of the recurrent nova T CrB in quiescence. T CrB is the first recurrent nova to be detected in the hard-X-ray band (E ~ 40.0 keV) during quiescence. The X-ray spectrum is consistent with cooling-flow emission emanating from an optically thin region in the boundary layer of an accretion disk around the white dwarf. The detection of strong stochastic flux variations in the light curve supports the interpretation of the hard X-ray emission as emanating from a boundary layer.