J/Psi mass shift in nuclear matter

Abstract

The $J/\Psi$ mass shift in cold nuclear matter is computed using an effective Lagrangian approach. The mass shift is computed by evaluating $D$ and $D^{\ast }$ meson loop contributions to the $J/\Psi$ self-energy employing medium-modified meson masses. The modification of the $D$ and $D^{\ast }$ masses in nuclear matter is obtained using the quark-meson coupling model. The loop integrals are regularized with dipole form factors and the sensitivity of the results to the values of form-factor cutoff masses is investigated. The $J/\Psi$ mass shift arising from the modification of the $D$ and $D^{\ast }$ loops at normal nuclear matter density is found to range from -16 MeV to -24 MeV under a wide variation of values of the cutoff masses. Experimental perspectives for the formation of a bound state of $J/\Psi$ to a nucleus are investigated.

Comments: 9 pages, latex file, 6 figures. Version published in Phys. Lett. B