Measurement of σ_x_(c2)B(x_(c2) →J/Ψγ)/σ_x_(c1)B(x_(c1) → J/Ψγ)in pp Collisions at s~(1/2) = 1.96 TeV

摘要

We measure the ratio of cross section times branching fraction, R_p = σ_x_(c2)B(x_(c2)→ J/Ψγ)/σ_x_(c1)B(x_(c1)→J/Ψγ), in 1.1 fb~(-1) of pp collisions at s~(1/2) = 1.96 TeV. This measurement covers the kinematic range p_T(J/Ψ) > 4.0 GeV/c, |η(J/Ψ) < 1.0, and p_T(γ) > 1.0 GeV/c. For events due to prompt processes, we find R_p = 0.395 ± 0.016(stat) ± 0.015(syst). This result represents a significant improvement in precision over previous measurements of prompt x_(c1,2) hadro production.