According to the classical understanding of newly-born neutron stars they should rotate more than 1000 times per second. Observations tell, however, that they rotate "only" 10 to 100 times per second and that their specific angular momentum is with 1014 cm2/s only 1% of the predicted values for angular momentum conservation. Neutron stars share this strong discrepancy with white dwarfs for which new spectroscopic observations give a maximum surface rotation rate of 10 km/s. This also leads to low values of the specific angular momentum, much less than expected. How is it possible?
