Measurement of the differential cross section $d\sigma/dt$ in elastic $p\bar p$ scattering at $\sqrt s=1.96\ \text{TeV}$

Abstract

We present a measurement of the elastic differential cross section $d\sigma(p\bar p \rightarrow p\bar p)/dt$ as a function of the four-momentum-transfer squared t. The data sample corresponds to an integrated luminosity of $\approx 31 \text{nb}^{−1}$ collected with the D0 detector using dedicated Tevatron $p\bar p$ Collider operating conditions at $\sqrt s=1.96 \text{TeV}$ and covers the range $0.26<|t|<1.2 \text{GeV}^2$. For $|t|<0.6 \text{GeV}^2, d\sigma/dt $ is described by an exponential function of the form $Ae^{−b|t|}$ with a slope parameter $b=16.86±0.10(\text{stat})±0.20(\text{syst}) \text{GeV}^{−2}$. A change in slope is observed at $|t|≈0.6 \text{GeV}^2$, followed by a more gradual $|t|$ dependence with increasing values of $|t|$.