Mid-rapidity anti-proton to proton ratio from Au+Au collisions at $\sqrt{s_{NN}}=130$ GeV

We report results on the ratio of mid-rapidity anti-proton to proton yields in Au+Au collisions at $\text{rts}=130$ GeV per nucleon pair as measured by the STAR experiment at RHIC. Within the rapidity and transverse momentum range of $\mathrm{\mid }y\mathrm{\mid }<0.5$ and 0.4 $<p_t<$ 1.0 GeV/$c$, the ratio is essentially independent of either transverse momentum or rapidity, with an average of $0.65\pm 0.01_{\rm (stat.)} \pm 0.07_{\rm (syst.)}$ for minimum bias collisions. Within errors, no strong centrality dependence is observed. The results indicate that at this RHIC energy, although the $p$-$\text{pb}$ pair production becomes important at mid-rapidity, a significant excess of baryons over anti-baryons is still present.