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

• Main Authors: Wieland, F. W, Barth, J, Glander, K. -H, Hannappel, J, Jöpen, N, Klein, F, Klempt, E, Lawall, R, Menze, D, Ostrick, M, Paul, E, Schulday, I, Schwille, W. J
• Format: Journal Article
• Language: English
• Published: 03.11.2010
• Subjects: Physics - Nuclear Experiment
• DOI: 10.48550/arxiv.1011.0822

The reaction $\gamma p \TO K^+\Lambda(1520)$ 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 $\Lambda(1520)$ production cross section was analyzed in the decay modes $pK^-$, $n \bar{K}^0$, $\Sigma^{\pm}\pi^{\mp}$, and $\Lambda\pi^+\pi^-$ 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 $\gamma p \TO K^+\Lambda(1520)$ 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 $\Lambda(1520)$ as a $\Sigma(1385)\pi$ molecule is not supported.