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

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.

7 pages, 6 figures, Accepted for publication in Monthly Notices of the Royal Astronomical Society Journal

References in corpus (6)

• Thermal and Bulk Comptonization in Accretion-Powered X-Ray Pulsars
• Discovery and Modeling of a Flattening of the Positive Cyclotron Line/Luminosity Relation in GX 304-1 with RXTE
• Decade long RXTE monitoring observations of Be/X-ray binary pulsar EXO 2030+375
• Suzaku observation of the transient X-ray pulsar GRO J1008-57
• Broad band X-ray spectroscopy of A0535+262 with SUZAKU
• A Suzaku View of Accretion Powered X-ray Pulsar GX 1+4

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• Insight-HXMT observations of Swift J0243.6+6124: the evolution of RMS pulse fractions at super-Eddington luminosity
• ULX pulsar Swift J0243.6+6124 observations with NuSTAR -- dominance of reflected emission in the super-Eddington state
• The Transient Ultra-luminous X-ray Source, ULX-4, in M51
• AstroSat detection of a mHz QPO and cyclotron line in IGR J19294+1816 during the 2019 outburst
• X-ray emission evolution of the Galactic ultra-luminous X-ray pulsar Swift J0243.6+6124 during the 2017-2018 outburst observed by the MAXI GSC
• Timing analysis of Swift J0243.6+6124 with NICER and Fermi/GBM during the decay phase of the 2017-2018 outburst
• An X-ray view of the 2021 outburst of SXP 15.6: constraints on the binary orbit and magnetic field of the Neutron Star