Formation of phase lags at the cyclotron energies in the pulse profiles of magnetized, accreting neutron stars
| dc.contributor.author | Schönherr, G. | |
| dc.contributor.author | Schwarm, F.-W. | |
| dc.contributor.author | Falkner, S. | |
| dc.contributor.author | Dauser, T. | |
| dc.contributor.author | Ferrigno, C. | |
| dc.contributor.author | Kühnel, M. | |
| dc.contributor.author | Klochkov, D. | |
| dc.contributor.author | Kretschmar, P. | |
| dc.contributor.author | Becker, P. A. | |
| dc.contributor.author | Wolff, M. T. | |
| dc.contributor.author | Pottschmidt, Katja | |
| dc.contributor.author | Falanga, M. | |
| dc.contributor.author | Kreykenbohm, I. | |
| dc.contributor.author | Fürst, F. | |
| dc.contributor.author | Staubert, R. | |
| dc.contributor.author | Wilms, J. | |
| dc.date.accessioned | 2023-09-06T14:42:14Z | |
| dc.date.available | 2023-09-06T14:42:14Z | |
| dc.date.issued | 2014-04-04 | |
| dc.description.abstract | Context. Accretion-powered X-ray pulsars show highly energy-dependent and complex pulse-profile morphologies. Significant deviations from the average pulse profile can appear, in particular close to the cyclotron line energies. These deviations can be described as energy-dependent phase lags, that is, as energy-dependent shifts of main features in the pulse profile. Aims. Using a numerical study we explore the effect of cyclotron resonant scattering on observable, energy-resolved pulse profiles. Methods. We generated the observable emission as a function of spin phase, using Monte Carlo simulations for cyclotron resonant scattering and a numerical ray-tracing routine accounting for general relativistic light-bending effects on the intrinsic emission from the accretion columns. Results. We find strong changes in the pulse profile coincident with the cyclotron line energies. Features in the pulse profile vary strongly with respect to the average pulse profile with the observing geometry and shift and smear out in energy additionally when assuming a non-static plasma. Conclusions. We demonstrate how phase lags at the cyclotron energies arise as a consequence of the effects of angular redistribution of X-rays by cyclotron resonance scattering in a strong magnetic field combined with relativistic effects. We also show that phase lags are strongly dependent on the accretion geometry. These intrinsic effects will in principle allow us to constrain a system’s accretion geometry. | en_US |
| dc.description.sponsorship | We thank the International Space Science Institute ISSI in Bern (CH) for granting two International Team meetings on “The physics of the accretion column of X-ray pulsars”, which have much inspired this collaborative work. We also thank the Bundesministerium für Wirtschaft und Technologie for funding through Deutsches Zentrum für Luft- und Raumfahrt grant 50 OR 1113. M.T.W. is supported by the US Office of Naval Research and the NASA ADAP Program under grant NNH13AV18I. We thank the anonymous referee for very useful comments. | en_US |
| dc.description.uri | https://www.aanda.org/articles/aa/full_html/2014/04/aa22448-13/aa22448-13.html | en_US |
| dc.format.extent | 4 pages | en_US |
| dc.genre | journal articles | en_US |
| dc.identifier | doi:10.13016/m2ctiz-5ku7 | |
| dc.identifier.citation | Schönherr, G., F.-W. Schwarm, S. Falkner, T. Dauser, C. Ferrigno, M. Kühnel, D. Klochkov, et al. “Formation of Phase Lags at the Cyclotron Energies in the Pulse Profiles of Magnetized, Accreting Neutron Stars.” Astronomy & Astrophysics 564 (April 1, 2014): L8. https://doi.org/10.1051/0004-6361/201322448. | en_US |
| dc.identifier.uri | https://doi.org/10.1051/0004-6361/201322448 | |
| dc.identifier.uri | http://hdl.handle.net/11603/29590 | |
| dc.language.iso | en_US | en_US |
| dc.publisher | EDP Sciences | en_US |
| dc.relation.isAvailableAt | The University of Maryland, Baltimore County (UMBC) | |
| dc.relation.ispartof | UMBC Center for Space Sciences and Technology | |
| dc.relation.ispartof | UMBC Faculty Collection | |
| dc.relation.ispartof | UMBC Physics Department | |
| dc.rights | This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law. | en_US |
| dc.rights | Public Domain Mark 1.0 | * |
| dc.rights.uri | http://creativecommons.org/publicdomain/mark/1.0/ | * |
| dc.title | Formation of phase lags at the cyclotron energies in the pulse profiles of magnetized, accreting neutron stars | en_US |
| dc.type | Text | en_US |
| dcterms.creator | https://orcid.org/0000-0002-4656-6881 | en_US |