MESONS IN THE MEDIUM:: EXPERIMENTS WITH CLAS AT JEFFERSON LAB.

In this article, we report on on investigations of the in-medium meson-nucleon interaction for the ω, ɸ, and $K_s^0$ mesons. Their in-medium cross sections and collisional widths can be measured by their absorption in a nucleus. In Hall B at the Thomas Jefferson National Accelerator Facility (JLab), the CLAS detector was used to study these long-lived mesons in nuclei. All of the mesons were produced by a photon beam with Eγ < 4 GeV in targets of 2H, C, Fe, and Pb. The vector mesons were reconstructed through their decay into e+e-. The $K_s^0$ mesons were measured with their dominant π+π- decay. The in-medium widths of the ω and ɸ mesons are found to be substantially larger than their values from the elementary reaction with a free nucleon. The analysis with the $K_s^0$ is preliminary, and its status will be discussd in this paper. [ABSTRACT FROM AUTHOR]