Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-19T12:31:12.858Z Has data issue: false hasContentIssue false
  • English
  • Français

The Zone of Avoidance as an X-ray absorber - the role of the galactic foreground modelling Swift XRT spectra

Published online by Cambridge University Press:  08 May 2018

I. I. Racz ,
Z. Bagoly ,
L. V. Tóth ,
L. G. Balázs ,
I. Horvath  and
S. Zahorecz
I. I. Racz
Affiliation:
Eötvös University, Budapest email: [email protected] MTA CSFK Konkoly Observatory, Budapest
Z. Bagoly
Affiliation:
Eötvös University, Budapest email: [email protected]
L. V. Tóth
Affiliation:
Eötvös University, Budapest email: [email protected] MTA CSFK Konkoly Observatory, Budapest
L. G. Balázs
Affiliation:
Eötvös University, Budapest email: [email protected] MTA CSFK Konkoly Observatory, Budapest
I. Horvath
Affiliation:
National University of Public Service, Budapest
S. Zahorecz
Affiliation:
Osaka Prefecture University, Sakai National Astronomical Observatory of Japan, Mitaka-shi
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Gamma-ray bursts (GRBs) are the most powerful explosive events in the Universe. The prompt gamma emission is followed by an X-ray afterglow that is also detected for over nine hundred GRBs by the Swift BAT and XRT detectors. The X-ray afterglow spectrum bears essential information about the burst, and the surrounding interstellar medium (ISM). Since the radiation travels through the line of sight intergalactic medium and the ISM in the Milky Way, the observed emission is influenced by extragalactic and galactic components. The column density of the Galactic foreground ranges several orders of magnitudes, due to both the large scale distribution of ISM and its small scale structures. We examined the effect of local HI column density on the penetrating X-ray emission, as the first step towards a precise modeling of the measured X-ray spectra. We fitted the X-ray spectra using the Xspec software, and checked how the shape of the initially power low spectrum changes with varying input Galactic HI column density. The total absorbing HI column is a sum of the intrinsic and Galactic component. We also investigated the model results for the intrinsic component varying the Galactic foreground. We found that such variations may alter the intrinsic hydrogen column density up to twenty-five percent. We will briefly discuss its consequences.

Keywords

gamma rays: burstsgamma rays: observationsX-rays: generalX-rays: ISM
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 12 , Symposium S333: Peering towards Cosmic Dawn , October 2017 , pp. 170 - 171
Copyright
Copyright © International Astronomical Union 2018 

References

Evans, P. A., Beardmore, A. P., Page, K. L., et al. 2007, A&A, 469, 379Google Scholar
Evans, P. A., Beardmore, A. P., Page, K. L., et al. 2009, MNRAS, 397, 1177CrossRefGoogle Scholar
Kumar, P. & Zhang, B., 2015, Phys. Rep., 561, 1CrossRefGoogle Scholar
Rácz, I. I., Bagoly, Z., Tóth, L. V., et al. 2017, Contributions of the Astronomical Observatory Skalnate Pleso, 47, 100Google Scholar