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High-Energy pulse profile of the Transient X-ray Pulsar SAX J2103.5+4545

M. Falanga·T. Di Salvo·L. Burderi·J. M. Bonnet-Bidaud·P. Goldoni·A. Goldwurm·G. Lavagetto·R. Iaria·N. R. Robba
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Abstract

In two recent INTEGRAL papers, Lutovinov et al. (2003) and Blay et al. (2004) report a timing and spectral analysis of the transient Be/X-ray pulsar SAX J2103.5+4545 at high energies (5--200 keV). In this work we present for the first time a study of the pulse profile at energies above 20 keV using INTEGRAL data. The spin-pulse profile shows a prominent (with a duty cycle of 14%) and broad (with a FWHM of ~ 51 s) peak and a secondary peak which becomes more evident above 20 keV. The pulsed fraction increases with energy from ~ 45% at 5--40 keV to ~ 80% at 40--80 keV. The morphology of the pulse profile also changes as a function of energy, consistent with variations in the spectral components that are visible in the pulse phase resolved spectra. A study of the double peaked profile shows that the difference in the two peaks can be modeled by a different scattering fraction between the radiation from the two magnetic poles.

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M. Falanga, T. Di Salvo, L. Burderi, J. M. Bonnet-Bidaud, P. Goldoni, A. Goldwurm, G. Lavagetto, R. Iaria, N. R. Robba. 2005-03-01. High-Energy pulse profile of the Transient X-ray Pulsar SAX J2103.5+4545. https://doi.org/10.1051/0004-6361%3A20042085

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