High P ²_⊥ Spin Theories

Abstract

Before discussing the “theories” it is necessary to define the subject more precisely. The best way to do so is to specify those high P ²_⊥ spin effects which must be described by the relevant theories. These effects provide “test facility” for “High P ²_⊥ Spin Theories”. They are listed below ^/1/:

• rapid increase and large value of analyzing power A observed in large angle pp-scattering at p _L = 28GeV/c (BNL);

• rapid increase of spin-spin correlation parameter A _nn(up to 60%) when energy grows from 6 to 12 GeV; there is an indication for oscillations with energy (ANL);

• single spin asymmetry increase with p _⊥ up to (20–40)% in inclusive π˚ — production processes in the central region (IHEP, CERN, FNAL).