Particle Physics Experiment

Particle physics, also called "high energy physics," is the study of the fundamental particles and their interactions. To explore such particles at the requisite subatomic distance scales requires particles with high energies, and most experiments use particle accelerators to produce them. According to our current understanding, embodied in a model known as the Standard Model, the true elementary particles - the building blocks of matter as we know it - are quarks and leptons. They interact through four types of forces - Strong, Electromagnetic, Weak, and Gravitational (although the gravitational force has not yet been incorporated into the model) - and acquire their masses through the Higgs boson, discovered at CERN in 2012. Quarks interact strongly - neutrons, protons, mesons, and hyperons are some of the more familiar particles containing them, called hadrons. Leptons are not susceptible to the strong force (we say they have a "strong charge" of zero), and include electrons, muons, taus, with an associated neutrino for each. Despite its remarkable success, the Standard Model leaves fundamental questions open, including the origin of neutrino masses, the nature of dark matter, and why the universe is made of matter rather than antimatter.

The experimental particle physics group at the University of Cincinnati consists of six faculty members, who conduct research programs at Fermilab, CERN, and KEK, in collaborative experiments with other institutions around the world. The group has local facilities to build and test detector concepts and components, including one of the four DUNE testing sites for far-detector front-end electronics. Software, including a growing body of machine-learning methods, is developed both locally and on-site. Faculty, postdoctoral fellows, and students travel frequently to remote accelerator labs to collect and analyze data.

Professor Adam Aurisano's research focuses on accelerator neutrino physics with the NOνA experiment at Fermilab and the Deep Underground Neutrino Experiment (DUNE), and on the development of machine-learning methods for neutrino physics and beyond. He leads NOνA's exotic oscillations group, which searches for sterile neutrinos, neutrino decay, and non-standard neutrino interactions, and he has contributed to major NOνA results, including a precision measurement of the oscillation parameters with ten years of data and the first joint oscillation analysis of the NOνA and T2K experiments, published in Nature in 2025. He also coordinates the final three-flavor oscillation analysis of the MINOS+ experiment. At DUNE, he co-leads the effort to measure tau-neutrino (ντ) appearance. The tau neutrino is the least explored of the three neutrino flavors, and DUNE's high-energy, high-intensity beam will produce large samples of tau neutrinos appearing through oscillations, providing a stringent test of the three-flavor neutrino paradigm and a window onto new physics. To find these rare events, his group developed NuGraph3, a graph neural network that reconstructs and selects tau-neutrino interactions in DUNE's liquid-argon detectors, and he has carried the same sparse convolutional network techniques into medical imaging, segmenting kidney tumors in CT scans. In 2026 he was appointed lead of NOνA's new AI Forum, which develops best practices for the use of large language models in research. Prof. Aurisano is also the principal investigator of the Department of Energy award that supports much of the Department's research in particle physics and cosmology.

Professor Conor Henderson works on the LHCb experiment at CERN's Large Hadron Collider, with support from the National Science Foundation. His group studies electroweak physics in the forward region, a kinematic range that complements the measurements of the central ATLAS and CMS detectors. They recently made the first measurement of the helicity of W bosons in the forward region, shown publicly at ICHEP 2026, and are completing the first forward measurement of W-boson pair production. The group also searches for rare processes that are highly sensitive to physics beyond the Standard Model, including rare four-body decays of B mesons and rare four-muon decays of the η and η′ mesons. Prof. Henderson co-convenes the work package responsible for the photomultiplier tubes, high voltage, and calibration system of the upgraded LHCb electromagnetic calorimeter, and is seeking support to develop an LED-based calibration system for the future LHCb Upgrade II. Through the NSF Institute for Research and Innovation in Software for High Energy Physics (IRIS-HEP), his group develops machine-learning algorithms for finding particle-collision vertices in LHCb's GPU-based real-time trigger. He also leads UC's QuarkNet Center, which brings local high school teachers and students into particle physics research.  

Professor Philip Ilten's research is focused on understanding the emergent properties of quantum chromodynamics and looking for possible connections between hidden dark sectors and ordinary matter. He works on the LHCb collaboration, where he served as simulation convener beginning in 2017 and as convener of the Higgs working group for the HL-LHC. From 2015 to 2017, Phil convened the soft QCD, electroweak, exotica, and heavy ions (QEE) physics working group within LHCb, building the non B-physics programme of LHCb. He now leads UC's work on CODEX-β, a demonstrator detector at LHCb designed to search for long-lived particles that could connect the Standard Model to a hidden sector, and on MLhad, which uses machine learning to model hadronization. Phil is particularly interested in combining experiment and theory into phenomenology. He is an author of the Pythia 8 event generation software, the creator of the Darkcast recasting package, and a developer for the HepMC 3 event record.

Professor Kinoshita's research is primarily in experimental particle physics. In particular, she investigates “heavy flavor” physics, a branch of the field studying decays of particles containing the heavy quarks known as c (charm) and b (beauty); she is a collaborator on the Belle II experiment, at the KEK accelerator facility in Japan. Important topics addressed by Belle II include violations of particle-antiparticle symmetry and searches for new particles and force laws beyond those already known. Her election in 2000 as a Fellow of the American Physical Society recognized her highly original work in this field. You can find more information on her website. 

Professor Schwartz studies weak interactions of heavy B and D mesons. His studies focus on measurements of quark-antiquark mixing and CP violation. He collaborates on the Belle and Belle II experiments that run at the KEK laboratory in Japan. His group has analyzed B⁰→π⁺π^- and B⁰→ρ⁺ρ^- decays, measuring the CKM weak phase φ₂, and B_s→D_s^(*)D_s^(*) decays, measuring the B_s-B_s oscillation parameter ΔΓ. Prof. Schwartz is co-leader of the Heavy Flavors Averaging Group, which is responsible for calculating world averages of fundamental parameters of heavy quark systems. For this group Prof. Schwartz calculates world average values of D⁰-D⁰ mixing and CP violation parameters using a global fit to over three dozen measured observables. Prof. Schwartz was also involved in the upgrade of the Belle detector to be used for the Belle II experiment, which has been taking data since 2019. For this upgrade Prof. Schwartz worked on the barrel particle identification system, which uses Cherenkov radiation generated in quartz bars to discriminate among different particle types, e.g., pions and kaons, and built a small prototype of this type of detector in his laboratory at UC. In 2008 Prof. Schwartz was elected a fellow of the American Physical Society.

Professor Alex Sousa's research is focused on searches for new neutrino phenomena and precision measurements of the neutrino properties. He participates in the NOνA experiment and the Deep Underground Neutrino Experiment (DUNE), both based at Fermilab, and was the physics coordinator of the MINOS+ experiment. NOνA uses the NuMI beam created at Fermilab and a 14 kton liquid scintillator far detector 500 miles away in Ash River, Minnesota, to study neutrino flavor oscillations, and has produced some of the world's most precise measurements of the neutrino oscillation parameters Δm232 and θ23, as well as constraints on the ordering of the neutrino masses and on CP violation in the neutrino sector, including in a joint analysis with Japan's T2K experiment. Prof. Sousa led the NOνA Test Beam program, which exposed a scaled-down NOνA detector to beams of identified particles at the Fermilab Test Beam Facility to precisely calibrate the NOνA detectors. With MINOS+, he led searches for a fourth, "sterile" neutrino that does not couple to weak interactions, setting stringent limits on the region of parameter space suggested by the LSND and MiniBooNE experiments. DUNE will send the world's most intense neutrino beam 800 miles from Fermilab to massive liquid-argon detectors 4,850 ft underground at the Sanford Underground Research Facility in South Dakota, with the goals of establishing whether neutrinos violate CP symmetry - a crucial step in resolving the matter-antimatter asymmetry of the Universe - determining the neutrino mass ordering, and detecting neutrinos from supernova bursts. Prof. Sousa co-convenes DUNE's Beam Beyond-the-Standard-Model physics group, which studies DUNE's sensitivity to sterile neutrinos, non-standard interactions, extra dimensions, and other new phenomena, and he is developing machine-learning anomaly detection for DUNE's data stream. His laboratory at UC is one of four sites worldwide testing the cold front-end electronics boards for the DUNE far detector, where undergraduate and graduate students characterize the boards at liquid-nitrogen temperatures, and the group has contributed to the readout electronics of the protoDUNE prototype detectors at the CERN Neutrino Platform.

Professor Randy Johnson's (Emeritus) research centers on neutrino interactions. He is presently participating in the MiniBooNE and MicroBooNE experiments at Fermilab and the Daya Bay Neutrino Experiment in China outside of Hong Kong. MiniBooNE is an experiment that is running at Fermilab that was designed to confirm or refute the evidence for a sterile neutrino originally seen by the LSND experiment at Los Alamos. The experiment seemed to refute LSND originally when running with a neutrino beam, but recently seems to confirm the result in antineutrino running (LSND is an antineutrino experiment). Data taking continues with this experiment. MicroBooNE is an experiment at Fermilab that will place a liquid argon time projection chamber in the same beamline as MiniBooNE. There it can both demonstrate the liquid argon technology and follow on MiniBooNE in testing the LSND result. The Daya Bay Neutrino Experiment is located at the Daya Bay Nuclear power plant in China. The experiment uses the plant as an intense source of electron anitneutrinos. In the mountains behind the plant, we have placed an arrange of antineutrino detectors. With these, we will be able to measure the disappearance probability of electron antineutrinos and, from that, the magnitude of the one unmeasured missing angle, θ13, in the neutrino sector.

Professors Mike Sokoloff and Brian Meadows (Emeritus) primarily study the interactions between weak forces that govern decays involving "heavy" quarks with exotic "flavors" (charm and beauty) into those with flavors that are manifest in "ordinary" atomic and nuclear matter. Such interactions take place over tiny distance scales (of order one thousandth of a proton radius) and correspondingly short time periods. They are followed by "long range" strong interactions which produce the decay products observed experimentally. Quantum mechanical interference effects produce time-dependent asymmetries in the decay rates of particles and their corresponding antiparticles. These variations allow measurements of weak interaction phases. A major goal of the research is to understand the extent to which these weak phases can be understood in terms of known physics (the Standard Model of particle physics) and the extent to which new physics (Physics Beyond the Standard Model) is required. The data they analyze presently come from the BaBar experiment at the SLAC National Laboratory, in California, and the LHCb experiment at CERN, in Switzerland. They also study the detailed properties of particles containing heavy quarks.