Dependence on the target-nucleus atomic number of spectra of lepton pairs produced in hadron-nucleus interactions

The dependence of lepton pair spectra (especially μ+μ- produced in hadron-nuclear interactions) on the atomic number A of the target-nucleus is analyzed over their effective mass m, longitudinal momentum psub(z) and transverse momentum psub(t). The investigation is carried out with such m, psub(z) and psub(t) at which the multiple rescattering of a projectile hadron or of soft multiple quark collisions give the main contribution into these spectra. It is shown that, if the spectra of μ+μ- over m and psub(t) are expressed in the form of Asup(α), taking into account such processes, it permits to describe the behaviour of α(m) and α(psub(t)) rather well with spectrum index α increasing from its minimum value to α approximately 1, if m or psub(t) increases