Evidence forρ0Production at Large Transverse Momentum

Abstract

We have extracted the ${\rho }^0$ inclusive cross section from ${\pi }^{+}p$ interactions at 6 and 22 GeV/c as a function of the longitudinal variables $y^{*}$ and $x$, and the transverse momentum $P_T$. The ratio of ${\rho }^0$ to $\pi$ inclusive cross sections is found to be rising linearly with ${P_T}^2$, and at $P_T\simeq 1$ GeV/c the ${\rho }^0$ and ${\pi }^{-}$ inclusive cross sections are equal. The implications of this observation for direct lepton production are discussed.