Color transparency in semi-inclusive electroproduction ofρmesons

Abstract

We study the electroproduction of $\ensuremath{\rho}$ mesons in nuclei at intermediate energies, deriving a treatment of the energy lost by the $\ensuremath{\rho}$ in each step of multiple scattering. This enables a close match between calculations and the experimental kinematic conditions. A standard Glauber calculation is presented, and then the effects of color-transparency are included. The influence of poor experimental resolution on the extracted transparency is assessed. The effects of $\ensuremath{\rho}$ meson decay inside the nucleus are examined, and are typically about 5% at most. This effect disappears rapidly as ${Q}^{2}$ increases from about 1 to 3 ${\mathrm{GeV}}^{2}$, causing a rise in the transparency that is not attributable to color transparency. The size of color transparency effects for C and Fe nuclei is studied for values of ${Q}^{2}$ up to 10 ${\mathrm{GeV}}^{2}$. The detailed results depend strongly on the assumed value of the $\ensuremath{\rho}N$ cross section. The overall effects of color transparency are greater than about 10% for both nuclear targets if ${Q}^{2}$ is greater than about 5 ${\mathrm{GeV}}^{2}$.