Observation of color-transparency in diffractive dissociation of pions

TL;DR

This study observes color-transparency effects in high-energy pion diffractive dissociation into di-jets, showing cross-section scaling consistent with theoretical predictions at asymptotic energies.

Contribution

It provides experimental evidence of color-transparency in pion dissociation, with cross-section scaling behavior matching theoretical models at high energies.

Findings

Cross-section scales as A^{1.6} for different nuclei.

Results agree with color-transparency theoretical predictions.

Supports the existence of color transparency in high-energy diffractive processes.

Abstract

We have studied the diffractive dissociation into di-jets of 500 GeV/c pions scattering coherently from carbon and platinum targets. Extrapolating to asymptotically high energies (where t_{min} approaches 0) we find that when the per-nucleus cross-section for this process is parameterized as $\sigma = \sigma_0 A^{\alpha}, \alpha$ has values near 1.6, the exact result depending on jet transverse momentum. These values are in agreement with those predicted by theoretical calculations of color-transparency.