New approaches to the crystal collimation

Possibilities of application of the effects of multiple volume reflection in one crystal and of the channeling efficiency increase by the crystal cut or buried oxide layer are applied for the first time to the problem of crystal collimation. It is demonstrated that both these effects decrease the nuclear reaction rate in the crystal scraper and increase the average impact parameter of collisions of deflected protons with an absorber. However the crystal cut is efficient at precise crystal orientation corresponding to the channeling conditions while the MVROC effect can be applied at relatively rough crystal alignment.