Grant: Discovery Grants Program - Individual

My research program focuses on atomic physics of simple atoms, largely exotic atoms including antimatter particles (positron (e+), antiproton (Pbar)). Much development has been dedicated to e+ systems for my 3 major research objectives at York, at the McMaster nuclear reactor (MNR) and at CERN. Positronic atoms with e+ bound to e- (Ps) or to an H- ion (e+H-) have been produced and continued measurements are proposed at York with extention at our new user facility at MNR. Continued trapped Antihydrogen (Hbar) and Pbar measurements are proposed at CERN.***Research is aimed at tests of fundamental physics including of QED and atomic theory. Comparisons of Hbar and hydrogen will test CPT, a corner stone of the Standard Model. ***     My research is highly anticipated in our field and in addition, contributes (e+ systems) to other research in other disciplines (eg solid state physics, materials science at MNR). My e+ and atomic physics work attract invitation to present at multiple international conferences annually. ***    e+ sources are based on radioactive beta+ decay of isotopes or pair production with intense gamma sources. For positronic atom physics (e+ bound to negatively charged particle, eg antiproton (Pbar), e-, H- .), e+ are slowed and then accumulated in a trap. Spectroscopy of these atoms requires many e+ to make sufficient atoms for high precision measurements and tests for systematic effects. We have improved on existing techniques and developed new ones, becoming a world leader, achieving record numbers and efficiencies for e+. Experiments at our newly developed user facility at the McMaster Intense Positron Beam Facility (MIPBF) at MNR are proposed that will further extend our capabilities with the much larger still expected e+ rates. We have developed the e+ production system near the reactor core and the beam guiding to send e+ to all users (eg. our apparatus for trapping e+ and experiments with positronic atoms). Over 100 times the e+ rate is expected. ***     In addition to these 3 major research programs, proposed contributions are also to 4 other experiments: I collaborate in precision measurements of helium fine-structure intervals and in a new program to re-measure the hydrogen Lamb shift at improved precision with the later aimed at solving the existing proton charge radius discrepancy puzzle. In addition the the Hbar trapping at CERN we have recently measured the antiproton magnetic moment at greatly improved precision. Next generation experiments proposed at CERN continue with the present Pbar beam time. Hbar research in our new apparatus will benefit from a new decelerator (ELENA) allowing increased Pbar trapping. Finally, in the proposed research, our experience depositing high purity neon crystals (e+ moderator) have led to research aimed at forming a new type of material, the electric equivalent of a permanent magnet, a permanent electret.**