Next-to-Leading Order QCD Corrections to the Drell-Yan Cross Section in Models of TeV-Scale Gravity

TL;DR

The paper addresses dilepton production via photon, Z, and graviton exchanges in models of TeV-scale gravity and provides the NLO QCD corrections to the Drell-Yan cross section. It develops the necessary coefficient functions for the gravity sector, performs real and virtual corrections, and demonstrates that NLO corrections produce sizable K-factors at the LHC and stabilize scale dependence. It quantifies the impact on observables: the invariant mass $Q$, the longitudinal momentum fraction $x_F$, the rapidity $Y$, and the forward–backward asymmetry $A_{FB}$, informing searches for extra dimensions. These results emphasize that NLO corrections are crucial for reliable bounds on the gravity scale $M_S$ at both the LHC and Tevatron.

Abstract

The first results on next-to-leading order QCD corrections to graviton-induced processes in hadron collisions in models of TeV-scale gravity are presented focusing on the case of dilepton pair production in \bar p p and pp collisions. Distributions in the invariant mass Q, the longitudinal fraction x_F, the rapidity Y and the forward-backward asymmetry of the lepton pair are studied. The quantitative impact of the QCD corrections for searches of extra dimensions at hadron colliders is investigated. It turns out that at the LHC (\sqrt{S}=14 TeV) the K-factor is rather large (K=1.6) for large invariant mass Q of the lepton pair, indicating the importance of accounting for these QCD corrections in the experimental search for TeV-scale gravity. At the Tevatron, the K-factor does not substantially deviate from the Standard Model value. However, its inclusion is necessitated to make the cross-section stable with respect to scale variations.

Figures (28)

• Figure 1: Ghost vertices
• Figure 2: Born contributions:
• Figure 3: Virtual corrections
• Figure 4: Virtual corrections, gluon loops.
• Figure 5: Virtual corrections, quark loops.