2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/157593Studying our semirelativistic potential model and the numerical results, which succeeds in predicting and reproducing recently discovered higher resonances of $D$, $D_s$, $B$, and $B_s$, we find a simple expression for the mass gap between two spin multiplets of heavy-light mesons, $(0^-,1^-)$ and $(0^+,1^+)$. The mass gap between chiral partners defined by $ΔM=M(0^+)-M(0^-)$ and/or $M(1^+)-M(1^-)$ is given by $ΔM=M(0^+)-M(0^-)=M(1^+)-M(1^-)\approx Λ_{\rm Q}-m_q$ in the limit of heavy quark symmetry. We also study the case including $1/m_Q$ corrections.8 pages, 2 figures, Invited talk given at the XII International Conference on Hadron Spectroscopy (Hadron 07), Frascati, October 8-13, 2007High Energy Physics - PhenomenologyHigh Energy Physics - Experimenttext