Lifetime-effect relations in the blocking technique for a thick crystal

Abstract
The change in blocking dip profiles due to compound nuclei recoil displacement during the lifetime (lifetime-effect relations) has been studied experimentally using the 27Al(p, α) 24Mg resonance reaction at an energy Er=633 keV and treated theoretically using the multistring model and the Fokker-Planck equation. The influence of the crystal thickness traversed by outgoing α-particles and the radiation defects present in the crystal on the lifetime-effect relations has been investigated. The importance of the inclusion of defects in calculations is demonstrated.