Abstract
Photoproduction reactions are dominated by isospin rules. In the case of πΔ photoproduction on the proton at forward π angles, the exchange of isospin = 1 meson(π or ρ) in the t-channel is the most dominant reaction mechanism, which is considered to give a cross section ratio σ(π+Δ0)/σ(π−Δ++) of 1/3. The cross section ratio has not been measured precisely experimentally. We present preliminary results for the cross section ratio at Eγ = 1.5–3.0 GeV. Larger ratios than 1/3 measured by our experiment at LEPS/SPring-8 suggest that the d̄d productions are enhanced compared with the ūu productions in the photoproduction reactions on the proton.
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Kohri, H., LEPS collaboration. Comparison between ūu and d̄d productions by the γp → π−Δ++ and π+Δ0 reactions at forward π angles at E γ = 1.5–3.0 GeV. Phys. Part. Nuclei 48, 63–68 (2017). https://doi.org/10.1134/S1063779617010129
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DOI: https://doi.org/10.1134/S1063779617010129