Photo-Production Of Neutral Kaons On C-12 In The Threshold Region

The kaon photo-production process on C-12 has been studied by measuring neutral kaons in the photon energy range of 0.8-1.1 GeV. Neutral kaons were identified by the invariant mass constructed from two charged pions emitted in the K-S(0) -> pi(+) pi(-) decay channel. The differential and integrated cross sections in the threshold photon energy region were obtained. The obtained momentum spectra were compared with a Spectator model calculation using elementary amplitudes of kaon photo-production given by recent isobar models. The present results provide the first information on the n(gamma, K-0)Lambda reaction, which is expected to play an important role in constructing models of strangeness production by electromagnetic interactions. The experimental results show that the cross section of C-12(gamma, K-0) is of the same order as that of C-12(gamma, K+) and suggest that a slightly backward K-0 angular distribution is favored in the gamma n -> K-0 Lambda process. (c) 2007 Elsevier B.V. All rights reserved.