Nuclear rotation for low and high spin values

It is shown that a rigorous application of the Peierls-Yoccoz angular momentum projection method leads, in the case ofK=0 rotational bands, to a simple exact expression for the projected energyE _I , which may be especially suitable for numerical calculations. On the basis of this energy law and without making any assumption for the overlapsn(Β) andh(Β), a finite expansion ofE _I in powers ofI( _I +1) is obtained and discussed. Using this finite series a microscopical variable moment of inertia model is presented.