An X-ray counterpart of HESS J1427-608 discovered with Suzaku

TL;DR

This paper reports the discovery of an X-ray counterpart to the gamma-ray source HESS J1427-608, identifying a diffuse X-ray source Suzaku J1427-6051 with specific spectral and spatial properties, supporting its association with the gamma-ray source.

Contribution

The study presents the first identification of an X-ray counterpart to HESS J1427-608, providing detailed spectral and morphological analysis that supports its classification as a diffuse source.

Findings

Suzaku J1427-6051 is a truly diffuse X-ray source.

The X-ray spectrum is well fitted by an absorbed power-law.

The source is likely associated with HESS J1427-608.

Abstract

We report the discovery of an X-ray counterpart of the unidentified very high energy gamma-ray source HESS J1427-608. In the sky field coincident with HESS J1427-608, an extended source was found in the 2-8 keV band, and was designated as Suzaku J1427-6051. Its X-ray radial profile has an extension of sigma=0.9' +/- 0.1' if approximated by a Gaussian. The spectrum was well fitted by an absorbed power-law with N_H=(1.1 +/- 0.3) times 10^23 cm^-2, Gamma=3.1 +0.6/-0.5, and the unabsorbed flux F_X=(9 +4/-2) times 10^-13 erg s^-1 cm^-2 in the 2-10 keV band. Using XMM-Newton archive data, we found seven point sources in the Suzaku source region. However, because their total flux and absorbing column densities are more than an order of magnitude lower than those of Suzaku J1427-6051, we consider that they are unrelated to the Suzaku source. Thus, Suzaku J1427-6051 is considered to be a truly diffuse source and an X-ray counterpart of HESS J1427-608. The possible nature of HESS J1427-608 is discussed based on the observational properties.