Radiative open charm decay of the Y(3940), Z(3930), X(4160) resonances

Understand

We determine the radiative decay amplitudes for decay into $D^*$ and $\bar{D} \gamma$, or $D^*_s$ and $\bar{D}_s \gamma$ of some of the charmonium like states classified as X,Y,Z resonances, plus some other hidden charm states which are dynamically generated from the interaction of vector mesons with charm.

• The mass distributions as a function of the $\bar{D} \gamma$ or $\bar{D}_s \gamma$ invariant mass show a peculiar behavior as a consequence of the $D^* \bar{D}^*$ nature of these states.
• The experimental search of these magnitudes can shed light on the nature of these states.