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Measurement of the beam-helicity asymmetry in photoproduction of $pi^{0}eta$ pairs on carbon, aluminum, and lead

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 نشر من قبل Vahe Sokhoyan
 تاريخ النشر 2019
  مجال البحث
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The beam-helicity asymmetry was measured, for the first time, in photoproduction of $pi^{0}eta$ pairs on carbon, aluminum, and lead, with the A2 experimental setup at MAMI. The results are compared to an earlier measurement on a free proton and to the corresponding theoretical calculations. The Mainz model is used to predict the beam-helicity asymmetry for the nuclear targets. The present results indicate that the photoproduction mechanism for $pi^{0}eta$ pairs on nuclei is similar to photoproduction on a free nucleon. This process is dominated by the $D_{33}$ partial wave with the $etaDelta(1232)$ intermediate state.



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