Using the data samples of 102 million Υ(1S) and 158 million
Υ(2S) events collected by the Belle detector, we search for a
pentaquark state in the pJ/ψ final state from Υ(1,2S) inclusive
decays. Here, the charge-conjugate p̅J/ψ is included. We observe
clear pJ/ψ production in Υ(1,2S) decays and measure the branching
fractions to be ℬ[Υ(1S) → pJ/ψ + anything] = [4.27 ±
0.16(stat.) ± 0.20(syst.)] × 10^-5 and ℬ[Υ(2S) →
pJ/ψ + anything] = [3.59 ± 0.14(stat.) ± 0.16(syst.)] × 10^-5.
We also measure the cross section of inclusive pJ/ψ production in e^+e^-
annihilation to be σ(e^+e^- → pJ/ψ + anything) = [57.5 ± 2.1
(stat.) ± 2.5(syst.)] fb at √(s) = 10.52 GeV using an
89.5 fb^-1 continuum data sample. There is no significant P_c(4312)^+,
P_c(4440)^+ or P_c(4457)^+ signal found in the pJ/ψ final states in
Υ(1,2S) inclusive decays. We determine the upper limits of
ℬ[Υ(1,2S)→ P_c^+ + anything] ·ℬ(P_c^+→
pJ/ψ) to be at the 10^-6 level.
