Nuclear dependence coefficient $\alpha (A,q_T)$ for the Drell-Yan and J/$\psi$ production

Define the nuclear dependence coefficient $\alpha (A,q_T)$ in terms of ratio of transverse momentum spectrum in hadron-nucleus and in hadron-nucleon collisions: $\frac{d\sigma^{hA}}{dq_T^2}/ \frac{d\sigma^{hN}}{dq_T^2}\equiv A^{\alpha(A,q_T)}$\mathrm{.}Wearguethatinsmall$q_T$region,the$\alpha(A,q_T)$fortheDrell-YanandJ\mathrm{/}$\psiproduction is given by a universal function:\a+b q_T^2$, where parameters a and b are completely determined by either calculable quantities or independently measurable physical observables. We demonstrate that this universal function $\alpha (A,q_T)$ is insensitive to the A for normal nuclear targets. For a color deconfined nuclear medium, the $\alpha (A,q_T)$ becomes strongly dependent on the A. We also show that our $\alpha (A,q_T)$ for the Drell-Yan process is naturally linked to perturbatively calculated $\alpha (A,q_T)$ at large $q_T$ without any free parameters, and the $\alpha (A,q_T)$ is consistent with E772 data for all $q_T$.