Production of χ _c1 and χ _c2 in pp̅ Collisions at √s= 1.8 TeV

Authors

T. Affolder, Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California
Kenneth A. Bloom, University of Nebraska-LincolnFollow
Collider Detector at Fermilab Collaboration

Date of this Version

4-30-2001

Comments

Published by American Physical Society. Phys. Rev. Lett. 86, 3963 (2001). http://prl.aps.org. Copyright © 2001 American Physical Society. Permission to use.

Abstract

We have measured the ratio of prompt production rates of the charmonium states χ _c1 and χ _c2 in 110 pb^-1 of pp̅ collisions at √s= 1.8 TeV. The photon from their decay into J/ψγ is reconstructed through conversion into e⁺e^- pairs. The energy resolution this technique provides makes the resolution of the two states possible. We find the ratio of production cross sections (σ _{χ c2}/ σ _{χ c1}=0.96 ± 0.27(stat) ± 0.11(syst) for events with p_T(J/ψ)> 4.0 GeV/c, |η(J/ψ)|, 0.6, and p_T( γ )>g> 1.0 GeV/c.