The Belle II Project

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The Belle II experiment will be located at the SuperKEKB e+e- collider at the KEK laboratory in Tsukuba, Japan. It is a successor to the successful Belle and BaBar experiments, which were cited for their contributions to the phenomenon of CP violation in the 2008 Physics Nobel Prize. The primary physics goal of Belle II is to search for evidence of new physics through a wide range of measurements that are sensitive to the presence of heavy virtual particles, and that can be precisely predicted in the Standard Model. These measurements could include CP violation and other asymmetries, rare decays, or forbidden decays. The mass reach of these measurements can exceed that of the direct searches by ATLAS and CMS. If new physics is found at the LHC, Belle II can explore its nature by looking for a pattern of deviations from the Standard Model. Belle II will also be sensitive to the direct production of new light particles, including those predicted by dark sector models of dark matter, or additional Higgs particles, particles that will be difficult to detect at the LHC. The experiment will also continue the exploration of the weak force and CP violation, a program successfully followed by BaBar and Belle. The number of possible measurements can be estimated by the 550 publications produced so far by BaBar. The Canadian Belle II group is preparing for the start of collisions in 2017 and data taking with the complete detector in 2018. Data taking will continue to 2024. Canada has two significant software/operational responsibilities in the calorimeter group: calibration and the GEANT simulation. Calibration will be a multi-year multi-person effort, starting now and extending throughout the project. Canada is also responsible for determining the distribution of detector material in simulation and in reality. A precise understanding of the material is an essential component in minimizing systematic errors, which become increasingly important in light of the high statistics to be collected. The group is responsible for predicting and monitoring beam backgrounds in the calorimeter, and providing the background levels in real time to the accelerator operators. Canadians are leading the low-multiplicity physics effort, which includes tau physics, direct searches for new particles, and electroweak measurements. Computing is an essential component of the experiment, with data sets approaching the size of LHC experiments. Canada is a key contributor of computing resources for the current generation of simulated events, and is developing the tools that will allow Belle II to fully utilize cloud computing. The group is requesting funds to support graduate students and postdocs to undertake the Canadian responsibilities and to produce physics results; for travel primarily to KEK, but also for conferences; material and supplies, including desktop and laptop computing; and common fund.