Quarks lie at the fundamental stratum of nature's constituents. The most recently discovered quark, the top quark, has some of the most mysterious properties of this particle family. Its large mass makes it a crucial probe of the yet undiscovered Higgs boson in particle physics. Understanding the properties of the top quark are a crucial test of the self-consistency of the Standard Model, especially as regards the properties of the Higgs Boson, recently discovered at the Large Hadron Collider and with confirming evidence from the Tevatron experiments at Fermilab.
A primary purpose of the D0 experiment is the measurement of the top quark's properties. Through Kehoe's efforts, SMU has been engaged in these studies primarily by measuring the top quark mass in two-lepton ('dilepton') events that have naturally low backgrounds. We have also been involved in the maintenance and upgrade of the hardware calorimeter trigger.