Colour Octet Contribution in Exclusive P-Wave Charmonium Decay into Proton-Antiproton

Abstract

In inclusive P-wave charmonium decay, to cancel infrared divergence in the colour singlet contribution requires the inclusion of the colour octet which becomes degenerate with the former in the infrared limit. In the corresponding exclusive decay, such an infrared divergence does not exist. On this ground, it becomes doubtful whether the colour octet is needed in exclusive reactions. A contradiction in the underlying picture, however, would result once all strong decay channels are summed. We provide an answer to this question in support of the colour octet with theoretical arguments as well as an explicit calculation of Chi_J ---> p \bar p.

25 pages latex file, 6 embedded PS figures, refined arguments, version to appear in Nucl. Phys. B

References in corpus (2)

• Colour-octet contributions to exclusive charmonium decays
• Study of the P-wave charmonium state χ_{cJ} in ψ(2S) decays

Cited by in corpus (8)

• Implications of light-quark admixtures on charmonium decays into meson pairs
• Measurement of ${\chi }_{cJ}$ decaying into $p\bar{n}{\pi }^{-}$ and $p\bar{n}{\pi }^{-}{\pi }^0$
• Observation of χ_{cJ} decaying into the p\bar{p}K^{+}K^{-} final state
• Revisiting the $P$-wave charmonium radiative decays $h_c\to \gamma {\eta }^{(\prime )}$ with relativistic corrections
• First Observation of Exclusive chi_cJ Decays to Two Charged and Two Neutral Hadrons
• First observations of $\psi (2S)$ and ${\chi }_{cJ}(1P)$ decays to four-body final states $h^{+}{h}^{-}{K}_S^0{K}_S^0$
• Color Octet Contribution in Exclusive P-Wave Charmonium Decay
• QCD analysis of the $P$-wave charmonium electromagnetic Dalitz decays $h_c\to {\eta }^{(\prime )}{\ell }^{+}{\ell }^{-}$