Professor Campbell's research is on the properties of elementary particles. He is currently working on the KOTO experiment at the JPARC accelerator facility in Tokai, Japan. The goal of this experiment is to measure the decay properties of the neutral kaon. Previously he worked at Fermilab on the CDF experiment. This large general-purpose detector was used to study the nature of proton-antiproton collisions at an energy of 1.8 TeV. The Top quark was discovered at this experiment, and Professor Campbell worked on several top quark and intermediate vector boson measurements.