Mass degeneracy of heavy-light mesons with chiral partner structure in the half-Skyrmion phase

We explore the mass splitting of heavy-light mesons with chiral partner structure in nuclear matter. In our calculation, we employed the heavy hadron chiral perturbation theory with chiral partner structure, and the nuclear matter is constructed by putting Skyrmions from the standard Skyrme model onto the face-centered cubic crystal and regarding the Skyrmion matter as nuclear matter. We find that, although the masses of heavy-light mesons with chiral partner structure are split in matter-free space and the Skyrmion phase, they are degenerated in the half-Skyrmion phase in which the chiral symmetry is restored globally. This observation suggests that the magnitude of the mass splitting of heavy-light mesons with chiral partner structure can be used as a probe of the phase structure of nuclear matter.