Astrophysics (Index)About

magnetic dipole braking

(magnetic dipole spin-down, magnetic breaking)
(the effect of a reduction in the spinning of a magnetic field)

Magnetic dipole breaking (or magnetic dipole spin-down or just magnetic breaking) is the tendency for a rotating magnetic field embedded in a non-rotating magnetic field to reduce its rotation. This generates magnetic dipole radiation which carries away the angular momentum and kinetic energy (KE). The slow reduction of the rotation of pulsars is presumed to result from this, but reduction is likely to be more pronounced at the time of the neutron star's birth.

The energy released by a pulsar's reduction in rotation is termed the spin-down luminosity, and the time it takes to spin down is the spin-down time (or spin-down timescale) calculated as the rotation's KE divided by the spin-down luminosity.

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