Broadband X-ray Spectral Study of Ultra-luminous X-ray Source M81 X--6

Abstract

Ultra-luminous X-ray sources (ULXs) are a class of extra-galactic, point-like, off-nuclear X-ray sources with X-ray luminosity from $\sim 10^{39}$~erg s${}^{-1}$ to $10^{41}$~erg s${}^{-1}$. We investigated the temporal and broadband X-ray spectral properties of the ULX M81~X--6 using simultaneous \textit{Suzaku} and \textit{NuSTAR} observations. To understand the nature of the source, we searched for pulsating signals from the source using the \textit{NuSTAR} observation. However, we failed to identify any strong pulsating signals from the source. Alternatively, the broadband spectral modelling with accreting magnetic neutron star continuum model provides a statistically acceptable fit, and the inferred spectral parameters and X-ray colours are consistent with other pulsating ULXs. Thus, our analysis suggests that M81~X--6 is another candidate ULX pulsar.

Accepted for Publication in MNRAS, 6 Pages, 4 Figures, 1 Table

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Cited by in corpus (4)

• Ultraluminous X-Ray Sources
• X-Ray Spectroscopy of Newly Identified ULXs Associated With M87's Globular Cluster Population
• The ultraluminous X-ray source M81 X-6: a weakly magnetised neutron star with a precessing accretion disc?
• Spectral and Temporal Properties of Ultra-luminous X-ray Source NGC 55 ULX1