Continued decay in the cyclotron line energy in Hercules X-1

Journal article
(Original article)


Publication Details

Author(s): Staubert R, Klochkov D, Vybornov V, Wilms J, Harrison FA
Journal: Astronomy & Astrophysics
Publisher: EDP Sciences
Publication year: 2016
Volume: 590
ISSN: 1432-0746


Abstract


The centroid energy E of the cyclotron line in the spectrum of the binary X-ray pulsar Her X-1 has been found to decrease with time on a time scale of a few tens of years - surprisingly short in astrophysical terms. This was found for the pulse phase-averaged line centroid energy using observational data from various X-ray satellites over the time period 1996 to 2012, establishing a reduction of ∼4 keV. Here we report on the result of a new observation by NuSTAR performed in August 2015. The earlier results are confirmed and strengthened with respect to both the dependence of E on flux (it is still present after 2006) and the dependence on time: the long-term decay continued with the same rate, corresponding to a reduction of ∼5 keV in 20 yr.



FAU Authors / FAU Editors

Wilms, Jörn Prof. Dr.
Professur für Astronomie und Astrophysik


External institutions with authors

California Institute of Technology (Caltech)
Eberhard Karls Universität Tübingen


How to cite

APA:
Staubert, R., Klochkov, D., Vybornov, V., Wilms, J., & Harrison, F.A. (2016). Continued decay in the cyclotron line energy in Hercules X-1. Astronomy & Astrophysics, 590. https://dx.doi.org/10.1051/0004-6361/201527955

MLA:
Staubert, R., et al. "Continued decay in the cyclotron line energy in Hercules X-1." Astronomy & Astrophysics 590 (2016).

BibTeX: 

Last updated on 2018-12-11 at 20:50