QCD corrections to Upsilon production via color-octet states at the Tevatron and LHC

TL;DR

This paper calculates next-to-leading order QCD corrections to Upsilon production via color-octet states at the Tevatron and LHC, providing refined cross section predictions and insights into polarization uncertainties.

Contribution

It presents the first NLO QCD correction calculations for Upsilon production via color-octet states at collider energies, improving theoretical predictions.

Findings

K factors are 1.313 and 1.379 at Tevatron; 1.044 and 1.182 at LHC.

Fitted color-octet matrix elements to experimental data.

Predicted Upsilon production and polarization with large uncertainties.

Abstract

The NLO QCD corrections to Upsilon production via S-wave color-octet states Upsilon(^1S_0^8,^3S_1^8) at the Tevatron and LHC is calculated. The K factors of total cross section (ratio of NLO to LO) are 1.313 and 1.379 for Upsilon(^1S_0^8) and Upsilon(^3S_1^8) at the Tevatron, while at the LHC they are 1.044 and 1.182, respectively. By fitting the experimental data from the D0, the matrix elements for S-wave color-octet states are obtained. And new predictions for Upsilon production are presented. The prediction for the polarization of inclusive Upsilon contains large uncertainty rising from the polarization of Upsilon from feed-down of chi_b. To further clarify the situation, new measurements on the production and polarization for direct Upsilon are expected.