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Angular asymmetries in the reactions pp \to dπ^+ηand pn \to dπ^0ηand a_0-f_0 mixing

A. E. Kudryavtsev·V. E. Tarasov·J. Haidenbauer·C. Hanhart·J. Speth
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Abstract

The reactions pp\to dπ^+ηand pn\to dπ^0ηare of special interest for investigating the a_0(980) (J^P=0^+) resonance in the process NN \to da_0 \to dπη. We study some aspects of those reactions within a general formalism and also in a concrete phenomenological model. In particular, it is shown that the presence of nonresonant (i.e. without excitation of the a_0 resonance) contributions to these reactions yields nonvanishing values for specific polarization observables, i.e. to effects like those generated by a_0-f_0 mixing. An experimental determination of these observables for the reaction pp\to dπ^+ηwould provide concrete information on the magnitude of those nonresonant contributions to πηproduction. We discuss also the possibility of extracting information about a_0-f_0 mixing from the reaction pn \to dπ^0ηwith polarized proton beam.

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A. E. Kudryavtsev, V. E. Tarasov, J. Haidenbauer, C. Hanhart, J. Speth. 2003-04-16. Angular asymmetries in the reactions pp \to dπ^+ηand pn \to dπ^0ηand a_0-f_0 mixing. https://doi.org/10.1134/1.1619506

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