No X-Ray Excess from the HESS J1741-302 Region except a New Intermediate Polar Candidate

Abstract

With the Suzaku satellite, we observed an unidentified TeV gamma-ray source HESS J1741$-$302 and its surroundings. No diffuse or point-like X-ray sources are detected from the bright southern emission peak of HESS J1741$-$302. From its neighborhood, we found a new intermediate polar candidate at the position of $(α, δ)_{\rm J2000.0} = (\timeform{17h40m35.6s}, \timeform{-30D14m16s})$, which is designated as Suzaku J174035.6$-$301416. The spectrum of Suzaku J174035.6$-$301416 exhibits emission lines at the energy of 6.4, 6.7 and 7.0 keV, which can be assigned as the K$\alpha$ lines from neutral, He-like and H-like iron, respectively. A coherent pulsation is found at a period of 432.1 $\pm$ 0.1 s. The pulse profile is quasi-sinusoidal in the hard X-ray band (4$-$8 keV), but is more complicated in the soft X-ray band (1$-$3 keV). The moderate period of pulsation, the energy flux, and the presence of the iron K$\alpha$ lines indicate that Suzaku J174035.6$-$301416 is likely an intermediate polar, a subclass of magnetized white dwarf binaries (cataclysmic variables). Based on these discoveries, we give some implications on the origin of GCDX and brief comments on HESS J1741$-$302 and PSR B1737$-$30.

Accepted by PASJ

References in corpus (5)

• Discrete sources as the origin of the Galactic X-ray ridge emission
• A Catalog of X-ray Point Sources from Two Megaseconds of Chandra Observations of the Galactic Center
• A systematic analysis of the broad Fe Kalpha line in neutron star LMXBs with XMM-Newton
• Why do some intermediate polars show soft X-ray emission? A survey of XMM-Newton spectra
• X-Ray Spectrum of a Peculiar Supernova Remnant G359.1-0.5

Cited by in corpus (7)

• Broad-band spectral analysis of the Galactic Ridge X-ray Emission
• HESS J1741-302: a hidden accelerator in the Galactic plane
• Multi-wavelength study of HESS J1741-302
• An intermediate polar candidate toward the Galactic plane
• Periodicity from X-ray sources within the inner Galactic disk
• Suzaku Discovery of Twin Thermal Plasma from the Tornado Nebula
• A high-magnetic-field radio pulsar survey with Swift/XRT