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Planar versus non-planar anti-NN annihilation into mesons in the light of anti-qq operators and the 1/Nc expansion

B. El-Bennich
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Abstract

It is argued that in the antiproton-proton annihilation into two mesons $\bar pp\longrightarrow m_1 m_2$, the origin of different restrictive angular momentum selection rules commonly obtained for planar annihilation diagrams $A2$ and for non-planar rearrangement diagrams $R2$ lies in the omission of momentum transfer between an annihilated antiquark-quark pair and a remaining quark or antiquark. If it is included, there is no reason for dismissing one type of diagram in favor of another one. Some considerations in the large $N_c$ limit of QCD equally shed light on the planar and non-planar contributions to the total $\bar NN\to m_1 m_2$ annihilation amplitude.

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B. El-Bennich. 2006-02-27. Planar versus non-planar anti-NN annihilation into mesons in the light of anti-qq operators and the 1/Nc expansion. https://doi.org/10.1103/physrevc.72.067001

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