Centrality dependence of charged particle multiplicity at midrapidity in Au+Au collisions atsNN=130 GeV

We present a measurement of the pseudorapidity density of primary charged particles near midrapidity in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}=130\mathrm{}\hspace{0.5em}\mathrm{GeV}$ as a function of the number of participating nucleons. The pseudorapidity density, ${\mathrm{dN}}_{\mathrm{ch}}/d\eta {|}_{|\eta |<1\mathrm{}}/\left(\frac{1}{2}〈N_{\mathrm{part}}〉\right),$ rises from $2.87\pm 0.21$ in peripheral events $\left(〈N_{\mathrm{part}}〉\sim 83\right)$ to $3.45\pm 0.18$ in central events $\left(〈N_{\mathrm{part}}〉\sim 353\right),$ which is $53\pm 8\%$ higher than $p\overline{p}$ collisions at a similar center-of-mass energy. This is consistent with an additional contribution to charged particle production that scales with the number of binary nucleon-nucleon collisions ${(N}_{\mathrm{coll}}).\mathrm{}$