$B_c,B_c^{\ast },B_s,B_s^{\ast },D_s$ and $D_s^{\ast }$ mass shift in a nuclear medium

Abstract

For the first time, we estimate the in-medium mass shift of the two-flavored heavy mesons $B_c,B_c^{\ast },B_s,B_s^{\ast },D_s$ and $D_s^{\ast }$ in symmetric nuclear matter. The estimates are made by evaluating the lowest order one-loop self-energies. The enhanced excitations of intermediate state heavy-light quark mesons in symmetric nuclear matter are the origin of their negative mass shift. Our results show that the magnitude of the mass shift for the $B_c$ meson ($\bar{b}c$ or $b\bar{c}$) is larger than those of the ${\eta }_c(\bar{c}c)$ and ${\eta }_b(\bar{b}b)$, different from a naive expectation that it would be in-between of them. While, that of the $B_c^{\ast }$ shows the in-between of the $J/\psi$ and ${\rm Y}$. We observe that the lighter vector meson excitation in each meson self-energy gives a dominant contribution for the corresponding meson mass shift, $B_c,B_s,$ and $D_s$.

Comments: Master's thesis