Improved measurement of absolute branching fraction of the inclusive decay Λc+→KS0X

By analyzing 4.5 fb⁻¹ of e⁺e⁻ collision data accumulated with the BESIII detector at center-of-mass energies ranging from 4599.53 MeV to 4698.82 MeV, we report the measurement of the absolute branching fraction (BF) of the inclusive decay Λc+→KS0X using the double-tag technique. The result is BΛc+→KS0X = (10.9 ± 0.2 ± 0.1)%, where the first uncertainty is statistical and the second is systematic. This result indicates that there are still undiscovered decay channels containing KS0 in the final state with a combined BF of (3.0 ± 0.4)%. The BF of the inclusive decay Λc+→K¯0/K0X is calculated to be BΛc+→K¯0/K0X = (21.8 ± 0.4 ± 0.2)%, The result is in agreement with the prediction of the statistical isospin model.