As. Arrott et al., ANGULAR-DEPENDENCE OF MAGNETIZATION IN RECORDING MEDIA .2. DECAY EFFECTS DUE TO MANY ROTATIONS, IEEE transactions on magnetics, 31(6), 1995, pp. 3790-3792
Rotational hysteresis measurements of commercial magnetic tapes are us
ed to extract the portion of the angular dependence of the magnetizati
on that remains after an Infinite number of cycles of rotation and to
identify the magnetic moment that disappears as n(-gamma) where n is t
he cycle number and gamma varies from 0.1 for fields below but compara
ble to the tape coercivity to 0.3 for higher and lower fields.