Angle Dependence of Polarization Observables by Fragmentation of Deuterons to Pions

Abstract

The fragmentation of deuterons into pions with nonzero angle emitted in the kinematical region forbidden for free nucleon-nucleon collisions is analyzed. The inclusive relativistic invariant spectrum of pions and the tensor analyzing power ${\rm A}_{YY}$ are investigated within the framework of an impulse approximation using different kinds of the deuteron wave function. The influence of ${\rm P}$-wave contribution to the deuteron wave function is studied, too. Our results are compared with the experimental data and other calculations performed within both the non-relativistic and relativistic approaches. It was found that theoretical calculations based on IA do not provide a consistent understanding of the new data in a whole cumulative region that can be caused by a influence of non-nucleon degrees of freedom.