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تسجيل مستخدم جديدThreshold $pi^-$ Photoproduction on the Neutron
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تأليف
W.J. Briscoe
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Recent data from the PIONS$@$MAX-lab Collaboration, measuring the total cross section of the pion incoherent photoproduction $gamma dtopi^-pp$ near threshold, have been used to extract the E$_{0+}$ multipole and total cross section of the reaction $gamma n!to!pi^-p$, also near threshold. These are the first measurements of the reaction $gamma dtopi^-pp$ in the threshold region. The value of E$_{0+}$ is extracted through a fit to the deuteron data in a photoproduction model accounting for final-state interactions. The model takes an $S$-wave approximation for the elementary reaction $gamma n!to!pi^-p$ with E$_{0+}! = $ const in the threshold region. The obtained value E$_{0+} = -31.86pm 0.8$ (in $10^{-3}/m_{pi^+}$ units) is in agreement with other existing results. Model predictions for the total cross section $sigma(gamma n!to!pi^-p)$ are also given.
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