Abstract
Abstract We use a simple toy-model to discuss global magnetohydrodynamic modes of a neutron star, taking into account the magnetic coupling between the elastic crust and the fluid core. Our results suggest that the notion of pure torsional crust modes is not useful for the coupled system. All modes excite Alfvén waves in the core. However, we also show that the modes that are most likely to be excited by a fractured crust, e.g. during a magnetar flare, are such that the crust and the core oscillate in concert. For our simple model, the frequencies of these modes are similar to the ‘pure crustal’ frequencies. In addition, our model provides a natural explanation for the presence of lower frequency (<30 Hz) quasi-periodic oscillations seen in the 2004 December giant flare of SGR 1806–20.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Monthly Notices of the Royal Astronomical Society: Letters
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
