Experimental study of the C12(Kstopped−,π0)BΛ12 reaction

The (K-stopped(-), pi(0)) strangeness and charge changing reaction was investigated by producing a B-12(Lambda) hypernucleus from a carbon target. The branching ratio for K- capture to the ground and p-shell states of this hypernucleus was found to be (0.28+/-0.08) x 10(-3) and (0.35+/-0.09)x10(-3), respectively, which after correction for isospin was lower than a previously measured value for the C-12(K-stopped(-),pi(-)) C-12(Lambda) reaction, but still above the theoretical predictions for the ground state. The experiment obtained a missing-mass resolution comparable to in-flight reactions, however the higher background and lower selectivity of the K-stopped(-) reaction limits its usefulness in the study of new hypernuclear species.