Beyond the Higgs boson at the Tevatron: detecting gluinos from Yukawa-unified SUSY

TL;DR

This paper explores the detection prospects of gluino pairs at the Tevatron collider within Yukawa-unified SUSY models, highlighting enhanced production rates and specific decay signatures involving multiple b-jets.

Contribution

It demonstrates that the Tevatron can potentially detect gluinos up to 400 GeV in mass in Yukawa-unified SUSY, extending beyond conventional SUSY search limits.

Findings

Gluino production cross section is enhanced due to suppressed negative interference.

Gluinos predominantly decay into three-body modes with b-quark pairs.

Tevatron can achieve a 5σ detection for gluino masses up to 400 GeV with 5 fb^{-1} data.

Abstract

Simple SUSY GUT models based on the gauge group SO(10) require t-b-\tau Yukawa coupling unification, in addition to gauge coupling and matter unification. The Yukawa coupling unification places strong constraints on the expected superparticle mass spectrum, with scalar masses \sim 10 TeV while gluino masses are much lighter: in the 300--500 GeV range. The very heavy squarks suppress negative interference in the q\bar{q}\to\tg\tg cross section, leading to a large enhancement in production rates. The gluinos decay almost always via three-body modes into a pair of b-quarks, so we expect at least four b-jets per signal event. We investigate the capability of Fermilab Tevatron collider experiments to detect gluino pair production in Yukawa-unified SUSY. By requiring events with large missing E_T and \ge 2 or 3 tagged b-jets, we find a 5\sigma reach in excess of m_{\tg}\sim 400 GeV for 5 fb^{-1} of data. This range in m_{\tg} is much further than the conventional Tevatron SUSY reach, and should cut a significant swath through the most favored region of parameter space for Yukawa-unified SUSY models.