Understanding the spectral and timing behavior of a newly discovered transient X-ray pulsar Swift J0243.6+6124

Gaurava K. Jaisawal; Sachindra Naik; J. Chenevez

doi:10.1093/mnras/stx3082

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arXiv · 1711.09813

Understanding the spectral and timing behavior of a newly discovered transient X-ray pulsar Swift J0243.6+6124

Gaurava K. Jaisawal·Sachindra Naik·J. Chenevez

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Abstract

We present the results obtained from timing and spectral studies of the newly discovered accreting X-ray binary pulsar Swift J0243.6+6124 using a NuSTAR observation in 2017 October at a flux level of ~280 mCrab. Pulsations at 9.85423(5) s were detected in the X-ray light curves of the pulsar. Pulse profiles of the pulsar were found to be strongly energy dependent. A broad profile at lower energies was found to evolve into a double peaked profile in $\ge$30keV. The 3-79 keV continuum spectrum of the pulsar was well described with a negative and positive exponential cutoff or high energy cutoff power law models modified with a hot blackbody at $\sim$3 keV. An iron emission line was also detected at 6.4 keV in the source spectrum. We did not find any signature of cyclotron absorption line in our study. Results obtained from phase-resolved and time-resolved spectroscopy are discussed in the paper.

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Gaurava K. Jaisawal, Sachindra Naik, J. Chenevez. 2017-11-27. Understanding the spectral and timing behavior of a newly discovered transient X-ray pulsar Swift J0243.6+6124. https://doi.org/10.1093/mnras%2Fstx3082

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