Production of K ∗(892) in K +N interactions at 3 GeV/ c

Abstract

We have studied the reactions K +d→K + π −pp,K +d→K o π o pp,K +d→K o π +pp, obtained from an exposure of the Saclay 81-cm bubble chamber filled with deuterium and exposed at CERN to a separated 3 GeV/ c K + beam. In reactions (1) and (2) there is abundant production of K ∗0(892) and some production of K ∗(1420). From the density matrix elements, it is found that K ∗0(892) is produced mainly by pion exchange. The K ∗(892) four-momentum-transfer distribution in reaction (1) agrees with the predictions of the OPE model, as modified by Dürr and Pilkuhn. A marked asymmetry of the decay distribution of the K + π − system is observed and discussed in the framework of a unitarized Veneziano model. In reaction (3), on the other hand, the production of K ∗+(892) and N ∗+(1236) is found to proceed mainly by vector exchange.