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arXiv · 1012.2126

Scaling and Resonances in Elementary K^+ Lambda Photoproduction

Reinhard A. Schumacher·Misak M. Sargsian
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Abstract

Recent cross section data for the reaction gamma + p \to K^+ + Lambda are examined for evidence of scaling in both the low-t Regge domain and in the high \sqrt{s} and -t domain where constituent counting may apply. It is shown that the reaction does scale in both regimes. At large center of mass angles, s^{-7} scaling appears to hold at essentially all -t, but with angle-dependent oscillations. The scaled data show particularly strong evidence for s-channel resonances for -t below 2 GeV^2 and for W below about 2.3 GeV. The dominant contributions are consistent with an N^* S_{11} resonance at 1690 MeV, a P_{13} at 1920 MeV, and a D_{13} resonance at 2100 MeV, which interfere to give the observed strong angular dependence.

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Reinhard A. Schumacher, Misak M. Sargsian. 2010-12-09. Scaling and Resonances in Elementary K^+ Lambda Photoproduction. https://doi.org/10.1103/physrevc.83.025207

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