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Quark Spin-flip in Pomeron Exchange

A Donnachie
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Abstract

It has been shown that the energy dependence of the reaction gamma p --> b1(1235) requires a contribution from pomeron exchange. This necessitates spin-flip at the quark level as the transition is from a 3S1 state to a 1P1 state. The same mechanism occurs in the reaction pi p --> a1(1260) p, which is a 1S0 to 3P1 transition.

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A Donnachie. 2005-08-25. Quark Spin-flip in Pomeron Exchange. https://arxiv.org/abs/hep-ph/0508262

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