Jimmy Law

Jimmy Law

Professor Emeritus

Contact Information

Email: jlaw@uoguelph.ca

Research Topics

Neutrino Physics, SNO Project

Present Research Activities

A major component of my research is the SNO Project. This Project is composed of a Solar Neutrino Detector, 2km underground, at the INCO Creighton Mine in Sudbury, Northern Ontario. It is built deep underground to shield from Cosmic ray activities and Muons, so that we can detect all the neutrinos from the SUN. The Detector was built and became operational in 1998, and have now solved the SOLAR NEUTRINO PROBLEM, by detecting all flavours of neutrinos from the SUN, in the 3 phases (pure D2O and also with the addition of 2 tons of Salt in the 1000 tons of D2O, and discrete Neutral Current Detectors immersed in the D2O). This means that the neutrinos have mass, so that they can morph into one another. This NCD phase ended on Nov 17, 2006, after we accumulated about a year of data. We have been involved in the calibration of the NCDs using radioactive sources (eg 252Cf, AmBe). My Student Marc Begevin, has introduced a multiring fitter, so that we can look at more exotic decays (e.g. N-Nbar), a Baryon number violation decay. My Post Doc Diane Reitzner, has been involved in the NCD phase, firstly looking at the calibration of Cf data, and later, some timings of the NCDs tubes, to see if they can be used in improving the efficiency for neutron detection. Currently she is working with the Low Energy Threshold Analysis Group looking at all the 3 phases of the data. In addition, we are working with Clarence Virtue, and Melin Huang of Laurentian University in attempting to probe CPT violation. The role of neutrino oscillation as a probe of CPT violation has been discussed by several authors. CPT invariance in neutrino oscillation implies that mass squared difference of say the 1 and 2 neutrinos should be the same as the corresponding anti-neutrino pair, as well as their mixing angles. A violation of these equality would signal violation of CPT invariance. This can be done using the SNO data for neutrinos and the KAMLAND data for antineutrinos.