Search for Long-Lived Massive Charged Particles in 1.96 TeV $\bar{p}p}$ Collisions

TL;DR

A signature-based search for long-lived charged massive particles produced in 1.0 fb-1 of pp[over ] collisions at sqrt[s]=1.96 TeV, collected with the CDF II detector using a high transverse-momentum (pT) muon trigger is performed.

Abstract

We performed a signature-based search for long-lived charged massive particles (CHAMPs) produced in 1.0 $\rm{fb}^{-1}$ of $\bar{p}p$ collisions at $\sqrt{s}=1.96$ TeV, collected with the CDF II detector using a high transverse-momentum ($p_T$) muon trigger. The search used time-of-flight to isolate slowly moving, high-$p_T$ particles. One event passed our selection cuts with an expected background of $1.9 \pm 0.2$ events. We set an upper bound on the production cross section, and, interpreting this result within the context of a stable scalar top quark model, set a lower limit on the particle mass of 249 GeV/$c^2$ at 95% C.L.

Figures (2)

• Figure 1: Observed (histogram) and predicted (band) mass distributions for candidate tracks in the muon sample. The curves on the right show the MC distributions expected for a 140 and a 220 GeV/$c^2$ long-lived stop.
• Figure 2: The observed 95% C.L. limits on the cross section for production of a stable top-squark pair (points), compared to the theoretical NLO cross section stop-prod (curve). The band represents theoretical and parton distribution function uncertainties. The intersection of the band with the limit curve yields a lower mass limit for a stable top squark of 249 GeV/$c^2$.