Results on Total and Elastic Cross Sections in Proton-Proton Collisions at $\sqrt{s}=200$ GeV

Abstract

We report results on the total and elastic cross sections in proton-proton collisions at $\sqrt{s}=200$ GeV obtained with the Roman Pot setup of the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The elastic differential cross section was measured in the squared four-momentum transfer range $0.045\le -t\le 0.135$ GeV${}^2$. The value of the exponential slope parameter $B$ of the elastic differential cross section $d\sigma /dt\sim e^{-Bt}$ in the measured $-t$ range was found to be $B=14.32\pm 0.09(stat.{)}_{-0.28}^{+0.13}(syst.)$ GeV${}^{-2}$. The total cross section ${\sigma }_{tot}$, obtained from extrapolation of the $d\sigma /dt$ to the optical point at $-t=0$, is ${\sigma }_{tot}=54.67\pm 0.21(stat.{)}_{-1.38}^{+1.28}(syst.)$ mb. We also present the values of the elastic cross section ${\sigma }_{el}=10.85\pm 0.03(stat.{)}_{-0.41}^{+0.49}(syst.)$ mb, the elastic cross section integrated within the STAR $t$-range ${\sigma }_{el}^{det}=4.05\pm 0.01(stat.{)}_{-0.17}^{+0.18}(syst.)$ mb, and the inelastic cross section ${\sigma }_{inel}=43.82\pm 0.21(stat.{)}_{-1.44}^{+1.37}(syst.)$ mb. The results are compared with the world data.

Updated version. New figure 4 and updated text. Accepted for publication in Phys. Lett. B