Cyclotron resonant scattering feature simulations II. Description of the CRSF simulation process

Journal article


Publication Details

Author(s): Schwarm FW, Ballhausen R, Falkner S, Schoenherr G, Pottschmidt K, Wolff MT, Becker PA, Furst F, Marcu-Cheatham DM, Hemphill PB, Sokolova-Lapa E, Dauser T, Klochkov D, Ferrigno C, Wilms J
Journal: Astronomy & Astrophysics
Publisher: EDP SCIENCES S A
Publication year: 2017
Volume: 601
ISSN: 1432-0746


Abstract

Context. Cyclotron resonant scattering features (CRSFs) are formed by scattering of X-ray photons off quantized plasma electrons in the strong magnetic field (of the order 10(12) G) close to the surface of an accreting X-ray pulsar. Due to the complex scattering cross-sections, the line profiles of CRSFs cannot be described by an analytic expression. Numerical methods, such as Monte Carlo (MC) simulations of the scattering processes, are required in order to predict precise line shapes for a given physical setup, which can be compared to observations to gain information about the underlying physics in these systems.Aims. A versatile simulation code is needed for the generation of synthetic cyclotron lines. Sophisticated geometries should be investigatable by making their simulation possible for the first time.Methods. The simulation utilizes the mean free path tables described in the first paper of this series for the fast interpolation of propagation lengths. The code is parallelized to make the very time-consuming simulations possible on convenient time scales. Furthermore, it can generate responses to monoenergetic photon injections, producing Green's functions, which can be used later to generate spectra for arbitrary continua.Results. We develop a new simulation code to generate synthetic cyclotron lines for complex scenarios, allowing for unprecedented physical interpretation of the observed data. An associated XSPEC model implementation is used to fit synthetic line profiles to NuSTAR data of Cep X-4. The code has been developed with the main goal of overcoming previous geometrical constraints in MC simulations of CRSFs. By applying this code also to more simple, classic geometries used in previous works, we furthermore address issues of code verification and cross-comparison of various models. The XSPEC model and the Green's function tables are available online (see link in footnote, page 1).


FAU Authors / FAU Editors

Ballhausen, Ralf
Dr.Karl-Remeis-Sternwarte Bamberg, Astronomisches Institut
Dauser, Thomas Dr.
Dr.Karl-Remeis-Sternwarte Bamberg, Astronomisches Institut
Falkner, Sebastian Dr.
Dr.Karl-Remeis-Sternwarte Bamberg, Astronomisches Institut
Schwarm, Fritz-Walter
Dr.Karl-Remeis-Sternwarte Bamberg, Astronomisches Institut
Wilms, Jörn Prof. Dr.
Professur für Astronomie und Astrophysik


External institutions with authors

Eberhard Karls Universität Tübingen
European Space Astronomy Centre (ESAC)
George Mason University
Leibniz Institute for Astrophysics Potsdam / Leibniz-Institut für Astrophysik Potsdam
Lomonosov Moscow State University / Московский государственный университет имени М.В.Ломоносова
Massachusetts Institute of Technology (MIT)
University of Geneva / Université de Genève (UNIGE)
University of Maryland, Baltimore County
U.S. Naval Research Laboratory


How to cite

APA:
Schwarm, F.-W., Ballhausen, R., Falkner, S., Schoenherr, G., Pottschmidt, K., Wolff, M.T.,... Wilms, J. (2017). Cyclotron resonant scattering feature simulations II. Description of the CRSF simulation process. Astronomy & Astrophysics, 601. https://dx.doi.org/10.1051/0004-6361/201630250

MLA:
Schwarm, Fritz-Walter, et al. "Cyclotron resonant scattering feature simulations II. Description of the CRSF simulation process." Astronomy & Astrophysics 601 (2017).

BibTeX: 

Last updated on 2019-07-06 at 09:08