Color transparency in $\pi^-$-induced dilepton production on nuclei

TL;DR

This paper discusses how observing color transparency in pion-induced dilepton production on nuclei can help extract nucleon structure and provides predictions for large transparency effects, with implications for understanding interaction dynamics and cross sections.

Contribution

It introduces the potential of using color transparency effects in pion-induced reactions to study nucleon structure and interaction dynamics at high energies.

Findings

Predicted large color transparency effects in specified kinematic range.

Suggested semiexclusive $ ho^0$ production reveals interaction dynamics.

Proposed $J/ar{J}$ production to measure interaction cross sections.

Abstract

We argue that the observation of the color transparency effect in the semiexclusive $A(\pi^-,l^+ l^-)$ process is important for determining whether it is possible to extract the generalized parton distributions of the nucleon from the elementary reaction $\pi^- p \to l^+ l^- n$ at $p_{\rm lab}=15-20$ GeV/c at small $|t|$ and large invariant mass of the dilepton pair $l^+ l^-$. Assuming that the transverse size of the pionic $q \bar q$ pair in the hard interaction point is similar to the one in the reaction $\gamma^* p\to \pi^+ n$ studied at JLab we predict large color transparency effects in the discussed kinematic range. We also suggest that the semiexclusive $\rho^0$ production in $\pi^-$-induced reactions in the same beam momentum region may provide new information on the dynamics of the interaction in the non-vacuum channel, while the $J/\psi$ production can be used to get information on $J/\psi N$ total interaction cross section.,