The experimental neutrino and astroparticle physics group at UW is involved in a number of large projects that offer a wide range of research opportunities to students in the department. The Wisconsin IceCube Particle Astrophysics Center (WIPAC), laboratory facilities in Chamberlin Hall, and the Physical Sciences Laboratory (PSL) offer unparalleled infrastructure and technical support for these exciting projects. For further information, explore the links to individual projects below. Some of the detectors are taking data, some are under construction, and some are at the planning stage. The group offers an ideal environment for experimental research, covering areas from data analysis to hardware.
UW–Madison is the lead institution for the IceCube project, which constructed the first kilometer-scale neutrino observatory, located at the South Pole. IceCube has opened a new window on the universe through the discovery of a flux of neutrinos reaching us from the cosmos with energies that exceed 10,000 TeV. In addition, a multimessenger campaign triggered by a 290-TeV IceCube neutrino identified the first cosmic accelerator producing neutrinos and cosmic rays. As a multipurpose facility, scientific analyses performed with IceCube data cover research areas such as neutrino physics, dark matter searches, and the search for physics beyond the Standard Model. WIPAC is embarking on an IceCube upgrade project that will lead to the construction of a next-generation detector, IceCube-Gen2.
The Askaryan Radio Array (ARA) is an R&D project at the South Pole consisting of five stations of radio receivers, located within 5 km of the South Pole and near IceCube. ARA is currently the most sensitive radio neutrino detector at high energies. It is designed to detect the radio pulses produced by interactions in the Antarctic ice of neutrinos with energies in excess of 10 PeV.
The Cherenkov Telescope Array (CTA) will use dozens of imaging atmospheric Cherenkov telescopes to detect gamma rays between 30 GeV and 100 TeV in energy. The main goals of CTA are to understand the nature of dark matter and of extreme objects in the universe, including supermassive black holes at the center of distant galaxies and the remnants of exploded stars, which are possible sources of cosmic rays.
We probe neutrino mass and mixing and study the fundamental properties of neutrinos in a variety of particle and nuclear physics experiments. UW is involved in the Daya Bay reactor experiment. Daya Bay has measured the third neutrino mixing angle theta13 and is currently taking data to increase the precision.
The NOvA experiment measures muon (anti)neutrino disappearance and electron (anti)neutrino appearance in the world’s most powerful neutrino beam, Fermilab’s NuMI beam. Its near detector at Fermilab measures the beam before any neutrino oscillations occur and the far detector in northern Minnesota measures the effect of oscillations. Both detectors are segmented liquid scintillator detectors. NOvA is searching for evidence of CP violation in the neutrino sector which could explain the origin of the matter/antimatter asymmetry in the Universe. NOvA is also studying the ordering of the neutrino masses.
DUNE is the next-generation neutrino oscillation experiment. The DUNE detectors will be giant liquid argon time projection chambers, and UW–Madison is responsible for building a significant portion of the active detector elements. DUNE will build on the results from NOvA to make precision measurements of CP violation and the neutrino mass ordering by observing neutrinos from a new and more powerful neutrino beam, LBNF.
CHIPS is a novel water Cherenkov detector designed to provide a cost-effective method for rapid deployment of a neutrino detector. It is located in northern Minnesota and is studying neutrino interactions from the Fermilab NuMI beam.
UW is also involved in the PROSPECT neutrino experiment. PROSPECT is a reactor neutrino experiment at very short baselines for making a precision measurement of the flux and energy spectrum of antineutrinos emitted from nuclear reactors. PROSPECT searches for the oscillation signature of sterile neutrinos.