J/psi (psi') production at the Tevatron and LHC at O(\alpha_s^4v^4) in nonrelativistic QCD

TL;DR

This paper provides a comprehensive next-to-leading order analysis of prompt J/psi and psi' production at the Tevatron and LHC within nonrelativistic QCD, including various production mechanisms and feeddown effects.

Contribution

It offers the first complete NLO evaluation of J/psi production including color-octet contributions and introduces new matrix element combinations that align predictions with experimental data.

Findings

NLO short-distance coefficients are significantly larger than LO, with a negative sign at high p_T.

New linear combinations of color-octet matrix elements are derived from CDF data.

Predictions for LHC J/psi production agree with CMS measurements.

Abstract

We present a complete evaluation for $\jpsi(\psip)$ prompt production at the Tevatron and LHC at next-to-leading order in nonrelativistic QCD, including color-singlet, color-octet, and higher charmonia feeddown contributions. The short-distance coefficients of $\pj$ at next-to-leading order are found to be larger than leading order by more than an order of magnitude but with a minus sign at high transverse momentum $p_T$. Two new linear combinations of color-octet matrix elements are obtained from the CDF data, and used to predict $\jpsi$ production at the LHC, which agrees with the CMS data. The possibility of $\sa$ dominance and the $\jpsi$ polarization puzzle are also discussed.