Differential cross section and photon beam asymmetry for the gamma n ->   K+ Sigma- reaction at Egamma=1.5-2.4 GeV
  Differential cross sections and photon beam asymmetries have been measured for the gamma n -> K+ Sigma- and gamma p -> K+ Sigma0 reactions separately using liquid deuterium and hydrogen targets with incident linearly polarized photon beams of Egamma=1.5-2.4 GeV at 0.6<cosTheta<1. The cross section ratio of sigma(K+Sigma-)/sigma(K+Sigma0), expected to be 2 on the basis of the isospin 1/2 exchange, is found to be close to 1. For the K+Sigma- reaction, large positive asymmetries are observed indicating the dominance of the K*-exchange. A large difference between the asymmetries for the K+Sigma- and K+Sigma0 reactions can not be explained by simple theoretical considerations. 
H. Kohri, D. S. Ahn, J. K. Ahn, H. Akimune, Y. Asano, W. C. Chang, S.   Date', H. Ejiri, S. Fukui, H. Fujimura, M. Fujiwara,...