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Has charge symmetry breaking been observed in the d d -> alpha pi0 reaction?

D. Dobrokhotov·G. Faldt·A. Gardestig·C. Wilkin
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Abstract

Estimates are made of the d d -> alpha gamma gamma production cross sections in a model where each neutron-proton pair in the beam and target initiates an n p -> d gamma reaction. This approach, which successfully reproduces observables in two-pion production at intermediate energies, suggests that direct two-photon production could provide a very significant background to the measurement of the charge-symmetry-breaking (CSB) reaction d d -> alpha pi0. A non-vanishing CSB cross section has been reported which might be confused with such two-photon production under the given experimental conditions.

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D. Dobrokhotov, G. Faldt, A. Gardestig, C. Wilkin. 1999-06-03. Has charge symmetry breaking been observed in the d d -> alpha pi0 reaction?. https://doi.org/10.1103/physrevlett.83.5246

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