Study of the many fluorescent lines and the absorption variability in GX 301-2 with XMM-Newton
Fürst F, Suchy S, Kreykenbohm I, Barragan L, Wilms J, Pottschmidt K, Caballero I, Kretschmar P, Ferrigno C, Rothschild RE (2011)
Publication Status: Published
Publication Type: Journal article
Publication year: 2011
Journal
Publisher: EDP SCIENCES S A
Book Volume: 535
Article Number: ARTN A9
DOI: 10.1051/0004-6361/201117665
Abstract
We present an in-depth study of the high mass X-ray binary (HMXB) GX 301-2 during its pre-periastron flare using data from the XMM-Newton satellite. The energy spectrum shows a power law continuum absorbed by a large equivalent hydrogen column on the order of 10(24) cm(-2) and a prominent Fe K alpha fluorescent emission line. Besides the Fe K alpha line, evidence for Fe K beta, Ni K alpha, Ni K beta, S K alpha, Ar K alpha, Ca K alpha, and Cr K alpha fluorescent lines is found. The observed line strengths are consistent with fluorescence in a cold absorber. This is the first time that Cr K alpha is seen in emission in the X-ray spectrum of a HMXB. In addition to the modulation by the strong pulse period of similar to 685 s the source is highly variable and shows different states of activity. We perform time-resolved as well as pulse-to-pulse resolved spectroscopy to investigate differences between these states of activity. We find that fluorescent line fluxes are strongly variable and generally follow the overall flux. The N-H value is variable by a factor of 2, but not correlated to continuum normalization. We find an interval of low flux in the light curve in which the pulsations cease almost completely, without any indication of an increasing absorption column. We investigate this dip in detail and argue that it is most likely that during the dip the accretion ceased and the afterglow of the fluorescent iron accounted for the main portion of the X-ray flux. A similar dip was found earlier in RXTE data, and we compare our findings to these results.
Authors with CRIS profile
Felix Fürst
Dr.Karl-Remeis-Sternwarte Bamberg, Astronomisches Institut
Ingo Kreykenbohm
Dr.Karl-Remeis-Sternwarte Bamberg, Astronomisches Institut
Jörn Wilms
Professur für Astronomie und Astrophysik
Involved external institutions
University of California, San Diego
United States (USA) (US)
University of Paris 7 - Denis Diderot / Université Paris VII Denis Diderot
France (FR)
University of Geneva / Université de Genève (UNIGE)
Switzerland (CH)
European Space Astronomy Centre (ESAC)
Spain (ES)
University of Maryland
United States (USA) (US)
United States (USA) (US)
University of Paris 7 - Denis Diderot / Université Paris VII Denis Diderot
France (FR)
University of Geneva / Université de Genève (UNIGE)
Switzerland (CH)
European Space Astronomy Centre (ESAC)
Spain (ES)
University of Maryland
United States (USA) (US)
How to cite
APA:
Fürst, F., Suchy, S., Kreykenbohm, I., Barragan, L., Wilms, J., Pottschmidt, K.,... Rothschild, R.E. (2011). Study of the many fluorescent lines and the absorption variability in GX 301-2 with XMM-Newton. Astronomy & Astrophysics, 535. https://doi.org/10.1051/0004-6361/201117665
MLA:
Fürst, Felix, et al. "Study of the many fluorescent lines and the absorption variability in GX 301-2 with XMM-Newton." Astronomy & Astrophysics 535 (2011).
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