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arXiv · 1011.0822

Measurement of the reaction $γp \TO K^ + Λ(1520)$ at photon energies up to 2.65 GeV

F. W. Wieland·J. Barth·K. -H. Glander·J. Hannappel·N. Jöpen·F. Klein·E. Klempt·R. Lawall·D. Menze·M. Ostrick·E. Paul·I. Schulday·W. J. Schwille
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Abstract

The reaction $γp \TO K^+Λ(1520)$ was measured in the energy range from threshold to 2.65 GeV with the SAPHIR detector at the electron stretcher facility ELSA in Bonn. The $Λ(1520)$ production cross section was analyzed in the decay modes $pK^-$, $n \bar{K}^0$, $Σ^{\pm}π^{\mp}$, and $Λπ^+π^-$ as a function of the photon energy and the squared four-momentum transfer $t$. While the cross sections for the inclusive reactions rise steadily with energy, the cross section of the process $γp \TO K^+Λ(1520)$ peaks at a photon energy of about 2.0 GeV, falls off exponentially with $t$, and shows a slope flattening with increasing photon energy. The angular distributions in the $t$-channel helicity system indicate neither a $K$ nor a $K^\star$ exchange dominance. The interpretation of the $Λ(1520)$ as a $Σ(1385)π$ molecule is not supported.

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BibTeXRIS

F. W. Wieland, J. Barth, K. -H. Glander, J. Hannappel, N. Jöpen, F. Klein, E. Klempt, R. Lawall, D. Menze, M. Ostrick, E. Paul, I. Schulday, W. J. Schwille. 2010-11-03. Measurement of the reaction $γp \TO K^ + Λ(1520)$ at photon energies up to 2.65 GeV. https://doi.org/10.1140/epja%2Fi2011-11133-1

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