Gluino-Squark Production at the LHC: The Threshold

TL;DR

This paper analyzes the production cross section of gluino-squark pairs near threshold at the LHC, revealing a significant enhancement from non-relativistic QCD effects and including various color configurations and NLO corrections.

Contribution

It provides a detailed non-relativistic QCD analysis of gluino-squark production near threshold, incorporating all color states and NLO Green's functions, which was not previously done.

Findings

Cross section enhancement of about 3% due to final state interactions.

All color configurations of S-wave gluino-squark pairs are considered.

Results are applied to benchmark scenarios based on Snowmass Points and Slopes.

Abstract

An analysis of the cross section for hadronic production of gluino-squark pairs close to threshold is presented. Within the framework of non-relativistic QCD a significant enhancement compared to fixed order perturbation theory is observed which originates from the characteristic remnants of the gluino-squark resonances below the nominal pair threshold. The analysis includes all colour configurations of S-wave gluino-squark pairs, i.e. triplet, sextet and 15 representation. Matching coefficients at leading order are separately evaluated for all colour configurations. The dominant QCD corrections, arising from initial- and final-state radiation are included. The non-relativistic dynamics of the gluino pair is solved by calculating the Green's function in Next-to-Leading Order (NLO). The results are applied to benchmark scenarios, based on Snowmass Points and Slopes (SPS). As a consequence of the large decay rate of at least one of the constituents squark or gluino annihilation decays of the bound state (\tilde{g}\tilde{q})\rightarrow gq, q\gamma, qZ or q'W^{\pm} are irrelevant. Thus the signatures of gluino-quark production below and above the nominal threshold are identical. Numerical results for the cross section at the Large Hadron Collider (LHC) at \sqrt{s}=7 TeV and 14 TeV are presented. The enhancement of the total cross section through final state interaction amounts to roughly 3%.