Does the enhancement observed in $\gamma \gamma \to D\bar{D}$ contain two $P$-wave higher charmonia?

Abstract

Solved is a new puzzle raised by the observation of an enhancement structure Z(3930) in $\gamma \gamma \to D\bar{D}$. If categorizing Z(3930) as ${\chi }_{c2}(2P)$ suggested by Belle and BaBar, we must explain why ${\chi }_{c0}(2P)$ dominantly decaying into $D\bar{D}$ is missing in the $D\bar{D}$ invariant mass spectrum. In this work, we propose that the Z(3930) enhancement structure may contain two $P$-wave higher charmonia {${\chi }_{c0}(2P)$} and ${\chi }_{c2}(2P)$. We show that this assumption is supported by our analysis of the $D\bar{D}$ invariant mass spectrum and $\cos {\theta }^{\ast }$ distribution of $\gamma \gamma \to D\bar{D}$. This observation would not only provide valuable information of two P-wave higher charmonia ${\chi }_{c0}(2P)$ and ${\chi }_{c2}(2P)$, but also serve as the crucial test of our novel proposal to the observed enhancement structure Z(3930), especially at the forthcoming BelleII and the approved SuperB.

5 pages, 2 tables, 3 figures. More contents and discussions added

Cited by in corpus (11)

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• Understanding the $0^{++}$ and $2^{++}$ charmonium(-like) states near 3.9 GeV
• Where are $3P$ and higher $P-$wave states in the charmonium family?
• Dispersive analysis of the $\gamma \gamma \to D\bar{D}$ data and the confirmation of the $D\bar{D}$ bound state
• The possibility of $X(4014)$ as a $D^{\ast }{\bar{D}}^{\ast }$ molecular state
• Role of the newly measured $B\to KD\bar{D}$ process to establish ${\chi }_{c0}(2P)$ state
• Connection between near the $D_s^{+}{D}_s^{-}$ threshold enhancement in $B^{+}\to D_s^{+}{D}_s^{-}{K}^{+}$ and conventional charmonium ${\chi }_{c0}(2P)$
• Radially Excited States of ${\eta }_c$
• Production of charmonium ${\chi }_{cJ}(2P)$ plus one $\omega$ meson by $e^{+}{e}^{-}$ annihilation
• Discovery potential of charmonium $2P$ states through the $e^{+}{e}^{-}\to \gamma D\bar{D}$ processes
• Proposed mixing between $2P$ and $1F$ wave charmonia