What Magnetar Seismology can Teach us about the Magnetic Fields

Abstract

The effect of magnetic fields on the frequencies of toroidal oscillations of neutron stars is derived to lowest order. Interpreting the fine structure in the QPO power spectrum of magnetars following giant flares reported by Strohmayer and Watts (2006) to be "Zeeman splitting" of degenerate toroidal modes, we estimate a crustal magnetic field of order 10^{15} Gauss or more. We suggest that residual m, -m symmetry following such splitting might allow beating of individual frequency components that is slow enough to be observed.

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Cited by in corpus (5)

• Magneto-elastic oscillations of neutron stars with dipolar magnetic fields
• Discovery of Quasi-Periodic Oscillations in the Recurrent Burst Emission from SGR 1806-20
• Powerful flares and magneto-elastic oscillations of magnetars
• Zeeman splitting of torsional oscillation frequencies of magnetars
• Zeeman effect in oscillations of magnetars with toroidal magnetic fields