Measurement of the absolute branching fraction of the inclusive decay Lambda c+-> KS0X: (BESIII Collaboration)

Abstract

We report the first measurement of the absolute branching fraction of the inclusive decay Lambda c+-> KS0X. The analysis is performed using an e+e- collision data sample corresponding to an integrated luminosity of 567 pb-1 taken at <mml:msqrt>s</mml:msqrt> = 4.6 GeV with the BESIII detector. Using eleven Cabibbo-favored Lambda <overbar></mml:mover>c- decay modes and the double-tag technique, this absolute branching fraction is measured to be B(Lambda c+-> KS0X)=(9.9 +/- 0.6 +/- 0.4)%, where the first uncertainty is statistical and the second systematic. The relative deviation between the branching fractions for the inclusive decay and the observed exclusive decays is (18.7 +/- 8.3)<mml:mo>%, which indicates that there may be some unobserved decay modes with a neutron or excited baryons in the final state.