Study of ϱ0 production in high multiplicity pp interactions at 300 GeV/c

We have searched for ϱ0 production in 85 high multiplicity events with 18 or more charged particles. We observe an enhancement at the ϱ0 mass but with a considerably narrower width. If we ignore this narrow width, we measure the cross section for pp → ϱ0 + n charged particles with n ⩾ 16 to be 1.81 ± 0.46 mb. The ratio between the number of ϱ0,s and π−,s is observed to increase from 0.08 ± 0.04 for pT < 0.6 GeV/c to 0.88 ± 0.23 for pT > 0.6 GeV/c.