Twisted magnetar magnetospheres

Ntotsikas, D., Gourgouliatos, K. N., Contopoulos, I. and Lander, S. K. (2024) Twisted magnetar magnetospheres. Monthly Notices of the Royal Astronomical Society, 527 (3). pp. 6691-6701. ISSN 0035-8711

Preview

PDF (stad3511) - Published Version Available under License Creative Commons Attribution. Download (1MB) | Preview

Abstract

Magnetar magnetospheres are strongly twisted, and are able to power sudden energetic events through the rapid release of stored electromagnetic energy. In this paper, we investigate twisted relativistic force-free axisymmetric magnetospheres of rotating neutron stars. We obtain numerical solutions of such configurations using the method of simultaneous relaxation for the magnetic field inside and outside the light-cylinder. We introduce a toroidal magnetic field in the region of closed field-lines that is associated with a poloidal electric current distribution in that region, and explore various mathematical expressions for that distribution. We find that, by increasing the twist, a larger fraction of magnetic field-lines crosses the light-cylinder and opens up to infinity, thus increasing the size of the polar caps and enhancing the spin-down rate. We also find that, for moderately to strongly twisted magnetospheres, the region of closed field-lines ends at some distance inside the light-cylinder. We discuss the implications of these solutions on the variation of magnetar spin-down rates, moding and nulling of pulsars, the relation between the angular shear and the twist, and the overall shape of the magnetosphere.

Item Type:	Article
Additional Information:	Funding Information: KNG acknowledges funding from grant FK 81641 ‘Theoretical and Computational Astrophysics’, ELKE, Special Account for Research Funds of the University of Patras.
Uncontrolled Keywords:	methods: numerical,mhd,astronomy and astrophysics,space and planetary science ,/dk/atira/pure/subjectarea/asjc/3100/3103
Faculty \ School:	Faculty of Science > School of Physics (former - to 2024)
Related URLs:	http://www.scopus.com/inward/record.url?...
Depositing User:	LivePure Connector
Date Deposited:	02 Jul 2024 12:32
Last Modified:	03 Aug 2024 01:09
URI:	https://ueaeprints.uea.ac.uk/id/eprint/95761
DOI:	10.1093/mnras/stad3511

Downloads

Actions (login required)

View Item