This web page summarizes the results for the measurement of σ(χ_c2)/σ(χ_c1) performed using the decay channel χ_c → J/ψ γ, based upon 1.1 fb^-1 of data.
The results have been approved as of June 15, 2006.

We measure:

•  σ(χ_c2)/σ(χ_c1) = 0.70 ± 0.04 (stat.)± 0.04 (sys.)± 0.06 (B.F.),  for prompt production

•  σ(χ_c2)/σ(χ_c1) = 0.25 ± 0.07 (stat.)± 0.01 (sys.)± 0.02 (B.F.),  for B decay production

A more detailed summary of the results can be found here: ps.

• Figure 1: J/ψ γ invariant mass, the full data sample (.eps)(.gif)
• Figure 2: Simulated χ_c → J/ψ γ events, mass plots for different P_T(J/ψ) (.eps)(.gif)
• Figure 3: Simulated χ_c → J/ψ γ events, mass plots for different P_T(J/ψ) (.eps)(.gif)
• Figure 4: J/ψ γ invariant mass, mass plots for different P_T(J/ψ)(.eps)(.gif)
• Figure 5: J/ψ γ invariant mass, mass plots for different P_T(J/ψ)(.eps)(.gif)
• Figure 6: J/ψ γ effective flight distance plots for different P_T(J/ψ)(.eps)(.gif)
• Figure 7: J/ψ γ effective flight distance plots for different P_T(J/ψ)(.eps)(.gif)
• Figure 8: σ(χ_c2)/σ(χ_c1) vs. P_T(J/ψ)  Systematic and Branching Fraction uncertainties are fully correlated between different values of P_T(J/ψ). (.eps)(.gif)