SCALING BEHAVIOUR OF TENSOR ANALYSING POWER (Ayy) IN THE INELASTIC SCATTERING OF RELATIVISTIC

We suggest a new dimensionless relativistic invariant variable R = ∆mX/ν which may be interpreted as the ratio of the excitation energy to the full transferred energy; therefore this variable measures a ”degree of inelasticity” of the scattering. Existing data on the tensor analysing power of the p(~ d, d ′)X and 12C(~ d, d ′)X inelastic scattering at momenta from 4.2 to 9 GeV/c are analysed in terms of this variable. We observe that Ayy taken as a function of R does not depend upon the incident energy, the scattering angle (up to the angles of θcm ∼ 30◦); there is no noticeable difference between the proton and nuclear targets as well. It is remarkable that Ayy is maximal (of ∼ 0.5) when R ∼ 0.5−0.6 and is small in absolute value when R is close to its limiting values of 0 and 1. Key-words: inelastic scattering, tensor analysing power, scaling, proton, deuteron, carbon.