Louisiana State University Physics & Astronomy

The Super-Kamiokande proton decay/neutrino experiment in Japan is a 50,000-ton water Cerenkov detector located 1,000 meters underground that used to measure the flux of neutrinos from the sun and from cosmic-ray interactions in the atmosphere, to search for neutrino bursts from supernova explosions, and to look for evidence of nucleon decay. Based on its observation of atmospheric neutrinos, Super-K is credited with producing the first compelling evidence that neutrinos have a mass and that the so called flavour eigenstates do not have a one-to-one correlation with the mass eigenstates but rather represent mixtures of the pure forms.

The neutrino long baseline experiment K2K uses a man-made neutrino beam which is monitored by a near detector and successively observed by the 250 km distant Super-K detector. Results from this accelerator based experimentalso show evidence for muon neutrino oscillations.

The Sudbury Neutrino Observatory (SNO) is a solar neutrino detector located 2 km underground in an active mine in Sudbury, Ontario, Canada. SNO is a water Cherenkov detector but unlike Super-K its core consists of heavy water which gives it the ability to separate the different types, also called flavors, of neutinos. By measuring the flavor content of the solar neutrino flux SNO was able to establish neutrino flavor transformations as the solution to the long standing solar neutrino problem. Data from SNO also allow to search for solar electron antineutrinos and 'invisible' nucleon decay and thereby constrain physics beyond the standardmodel of particle physics.

The KamLAND experiment (also in Japan), which uses distant nuclear reactors as antineutrino sources, observed a KamLAND

deficit in the expected antineutrino flux. Under the assumption that neutrinos and antineutrinos behave the same way (also called CPT conservation), results from KamLAND confirm the mixing phenomenon seen in solar neutrinos.

The MiniBooNE experiment at Fermilab aims to solve the mistery about the existence of the hypothesized 'sterile' neutrino. This fourth type of neutrino is even more elusive than the previously observed electron, muon and tauon type neutrinos.

In addition to our continuing involvement in the above experiments, our group is also working on two upcoming projects:

Double-CHOOZ; a reactor experiment located in France whose goal it is to measure the final unknown neutrino mixing angle. This experiment is expected to start running in 2007.
T2K: an experiment to send an intense off-axis neutrino beam from the new accelerator complex being built in Tokai, northeast of Tokyo, to the Super-K detector 295 km away. The goal is to measure neutrino mixing parameters and investigate the neutrino mass hierarchy and to look for evidence of CP violation.

Currently, both of the new projects (Double-CHOOZ and T2K) as well as SNO have RA's available.