Magnetic-Dipole Alignment in Pulsars

If the explanation of pulsars involves classical magnetic-dipole radiation of a rotating dipole that makes the angle `kwith the rotation axis, the radiation reaction causes `k to decrease with time and the frequency to approach cos times the current frequency, n = ,ttv/( ,t)2 = 3 + 2 cot2 `p. The values of p and p, for the Crab pulsar imply 48?4 < `p < 131?6 and n < 4.66.