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Two-body Mechanisms in Pion Photoproduction on the Trinucleon

S. S. Kamalov·L. Tiator·C. Bennhold
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Abstract

A breakdown of the Impulse Approximation is studied in pion photoproduction on $^3$He at high momentum transfers. The usual DWIA formalism with Faddeev wave functions which works well for small momentum transfers deviates from experimental measurements by up to two orders of magnitude for $Q^2>6 fm^{-2}$. It is found that the explicit inclusion of two-body mechanisms, where the photon is absorbed on one nucleon and the pion is emitted from another nucleon can restore agreement with the data.

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S. S. Kamalov, L. Tiator, C. Bennhold. 1994-10-12. Two-body Mechanisms in Pion Photoproduction on the Trinucleon. https://doi.org/10.1103/physrevlett.75.1288

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