Comment on the new $D_s^{(\ast )+}{\pi }^0$ resonances

Abstract

We propose an explanation of the new resonances observed in $D_s^{(\ast )+}{\pi }^0$ decays. We suggest that the data can be explained by the mixing of conventional p-wave excited $D_s^{+}$ mesons with 4-quark states. The narrow states observed in $D_s^{+}{\pi }^0$ and $D_s^{\ast +}{\pi }^0$ are primarily p-wave $D_{sJ}^{\ast }$ states, while the predominantly 4-quark states are shifted above $D^{(\ast )}K$ threshold and should be broad. Ranges for the mixing parameter and mass of the 4-quark state in this scenario are given. Other experimental consequences are discussed.

Comments: 4 pages, 2 figures. Updated references. To appear in Phys. Lett. B