Attenuation ofωmesons in cold nuclear matter

Abstract

The attenuation of $\ensuremath{\omega}$ mesons in cold nuclear matter has been investigated via the time-dependent multiple-scattering Monte Carlo multicollisional (MCMC) intranuclear cascade model. The inelastic $\ensuremath{\omega}$ width deduced from CBELSA/TAPS Collaboration data of meson transparency in complex nuclei (${\ensuremath{\Gamma}}^{*}\ensuremath{\simeq}30$ MeV/c${}^{2}$) is approximately 5 times lower than the value obtained with recent theoretical models and consistent with an in-medium total $\ensuremath{\omega}N$ cross section within 25--30 mb for an average meson momentum of 1.1 GeV/c . The momentum-dependent transparency ratios suggest an elastic/total cross-section ratio around 40$%$. For the case of CLAS Collaboration data a much higher width is deduced $({\ensuremath{\Gamma}}^{*}\ensuremath{\gtrsim}120$ MeV/c${}^{2}),$ with the MCMC model providing a consistent interpretation of the data, assuming a much higher meson absorption (${\ensuremath{\sigma}}_{\ensuremath{\omega}N}^{*}\ensuremath{\gtrsim}100$ mb) for ${p}_{\ensuremath{\omega}}\ensuremath{\sim}1.7$ GeV/c.