Colored Resonant Signals at the LHC: Largest Rate and Simplest Topology

TL;DR

This work develops a general, group-theory–based framework to study colored resonances at the LHC, classifying possible states by $SU(3)_C\times SU(2)_L\times U(1)_Y$ and constructing minimal effective couplings to light partons. It derives analytic production-rate formulas for diverse color representations across initial states ($3\otimes3$, $3\otimes8$, $8\otimes8$, $3\otimes\bar{3}$) and computes hadronic cross sections at $7$ and $14$ TeV using parton luminosities, incorporating narrow width approximations and typical QCD K-factors. The paper then confronts these predictions with ATLAS/CMS dijet data to place bounds on resonance masses and couplings, finding lower limits in the range $0.9$–$2.7\ \mathrm{TeV}$ for unit couplings. Overall, it provides a comprehensive, ready-to-use framework for predicting and constraining TeV-scale colored resonances with dijet signatures and sets the stage for exploring additional decay channels in future LHC analyses.

Abstract

We study the colored resonance production at the LHC in a most general approach. We classify the possible colored resonances based on group theory decomposition, and construct their effective interactions with light partons. The production cross section from annihilation of valence quarks or gluons may be on the order of 400 - 1000 pb at LHC energies for a mass of 1 TeV with nominal couplings, leading to the largest production rates for new physics at the TeV scale, and simplest event topology with dijet final states. We apply the new dijet data from the LHC experiments to put bounds on various possible colored resonant states. The current bounds range from 0.9 to 2.7 TeV. The formulation is readily applicable for future searches including other decay modes.

Figures (9)

• Figure 1: The parton luminosities $dL_{ij} / d\tau$ versus resonance mass at the (a) 7 TeV and (b) 14 TeV LHC.
• Figure 2: Center of momentum system rapidity distributions for resonance mass of $1.5$ TeV and initial states $gg,uu,u\bar{u}$ and $ug$ at the (a) 7 and (b) 14 TeV LHC.
• Figure 3: Dijet cross sections for color-sextet vector production via $uu, ud$ and $dd$ initial states versus its mass at the LHC for (a) 7 TeV and (b) 14 TeV. Subleading contributions from antiquarks for the conjugate particle production are also included. The coupling constant to initial state partons and the branching fraction to dijet have been factorized out.
• Figure 4: Dijet cross sections for color-sextet fermion production via $ug$ and $dg$ initial states versus its mass at the LHC for (a) 7 TeV and (b) 14 TeV. Subleading contributions from antiquarks for the conjugate particle production are also included. The coupling constant to initial state partons and the branching fraction to dijet have been factorized out. The new physics scale, $\Lambda$, has been set equal to $2M$.
• Figure 5: Dijet cross sections for color-octet scalar production via $gg$ initial states versus its mass at the LHC for 7 TeV (dashed curve) and 14 TeV (solid curve). The coupling constant to initial state partons and the branching fraction to dijet have been factorized out. The new physics scale, $\Lambda$, has been set equal to $M$.