Magnetic field instabiities in neutron stars

• Published in: Astronomische Nachrichten Vol. 335; no. 3; pp. 285 - 290
• Main Author: Ciolfi, R.
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag 01.03.2014; WILEY‐VCH Verlag; Wiley Subscription Services, Inc
• Subjects: Astronomical instruments; gravitational waves; Magnetic fields; magnetohydrodynamics (MHD); Neutron stars; Neutrons; Nonlinearity; Perturbation theory; relativity; Simulation; Stability; Stars & galaxies; stars: magnetic fields; stars: neutron; State of the art
• ISSN: 0004-6337; 1521-3994
• DOI: 10.1002/asna.201312033

Magnetic fields represent a crucial aspect of the physics and astro‐physics of neutron stars. Despite its great relevance, the internal magnetic field configuration of neutron stars is very poorly constrained by the observations, and understanding its properties is a long‐standing theoretical challenge. The investigation on the subject is focused on the search for those magnetic field geometries which are stable on several Alfvèn timescales, thus constituting a viable description of neutron star interiors. Assessing the stability of a given magnetic field geometry is therefore an important part of this research. So far only simple configurations, such as the purely poloidal or purely toroidal ones, have been studied in detail in perturbation theory and, most recently, by means of nonlinear magnetohydrodynamic simulations. Here we review the basic results of the state‐of‐the‐art general relativistic nonlinear studies, discussing the present status of the field and its future directions. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)