  With the experimental data from STAR, PHENIX and BRAHMS on the centrality and
rapidity dependence of the $p_T$ spectrum in Au+Au and d+Au collisions, we show
that there exists a scaling distribution which is independent of the colliding
system, centrality and rapidity. The parameter for the average transverse
momentum $<p_T>$ increases from peripheral to central d+Au collisions. This
increase accounts for the enhancement of particle production in those
collisions. A non-extensive entropy is used to derive the scaling function.
