A Study of Strangeness Production and Decay Processes using a Very Forward Particle Trigger in Photo- and Electroproduction

We propose to to study the production of various strange particles and strange nuclear systems using photoand electro-production at zero degrees in combination with a very forward angle particle trigger. The new feature of this LOI is that a kaon trigger is implemented for kaons produced at angles le15 degrees. In addition, for electroproduction processes the the scattered electrons are also detected at essentially zero degrees with respect to the incident beam. As an example on the physics to be studied, we would propose to investigate the dynamical behavior of the ∆I = 1/2 rule by measuring nucleon emission in the non-mesonic decay of the ΛH hypernucleus. For this experiment, energy resolution sufficient to identify the production of a hypernucleus is necessary (≈ 10 MeV FWHM. The hypernuclear decay products are detected in CLAS. The experiment uses photons, either real or virtual, incident on a liquid He target to produce the 4 ΛH hypernucleus via the (γ,K ) reaction. The goal of the experiment is to combine the measured strength of the neutron and proton stimulated decays from this hypernucleus with similar values from other s-shell hypernuclei, in order to obtain a definitive test of the ∆I=1/2 rule in a high momentum-transfer, weak decay. We intend to obtain both coincident and singles spectra of the neutron and proton stimulated decay.