LHC Phenomenology of Lowest Massive Regge Recurrences in the Randall-Sundrum Orbifold

TL;DR

This paper investigates the potential for detecting lowest massive Regge excitations of gluons and gauge bosons predicted by string theory in Randall-Sundrum models at the LHC, focusing on dijet and photon+jet channels.

Contribution

It provides a detailed analysis of the LHC discovery potential for Regge excitations in warped extra-dimensional models using collider data and amplitude calculations.

Findings

5σ discovery reach up to 4.7 TeV with 100 fb^{-1}

Resonant structures in photon+jet can confirm string physics up to 3.0 TeV

Dijet mass spectrum ratios can probe states around 2.5 TeV with early data

Abstract

We consider string realizations of the Randall-Sundrum effective theory for electroweak symmetry breaking and explore the search for the lowest massive Regge excitation of the gluon and of the extra (color singlet) gauge boson inherent of D-brane constructions. In these curved backgrounds, the higher-spin Regge recurrences of Standard Model fields localized near the IR brane are warped down to close to the TeV range and hence can be produced at collider experiments. Assuming that the theory is weakly coupled, we make use of four gauge boson amplitudes evaluated near the first Regge pole to determine the discovery potential of LHC. We study the inclusive dijet mass spectrum in the central rapidity region |y_{jet}| < 1.0 for dijet masses M \geq 2.5 TeV. We find that with an integrated luminosity of 100 fb^{-1}, the 5\sigma discovery reach can be as high as 4.7 TeV. Observations of resonant structures in pp \rightarrow direct \gamma + jet can provide interesting corroboration for string physics up to 3.0 TeV. We also study the ratio of dijet mass spectra at small and large scattering angles. We show that with the first fb^{-1} such a ratio can probe lowest-lying Regge states for masses \sim 2.5 TeV.