| Speaker: | Takeo Higuchi (KEK, High Energy Accelerator Organization) |
|---|---|
| Title: | The Upcoming Grand Challenge by the Super B-Factory Experiment |
| Date (JST): | Mon, Feb 27, 2012, 13:30 - 15:00 |
| Place: | Lecture Hall |
| Related File: | 619.pdf |
| Abstract: |
The verification of the Kobayashi-Maskawa theory is one of the most remarkable outcomes of the B-factory experiments, Belle and BaBar. In the B-factory experiments, we observed a large CP violation between the B0 and B0bar mesons, which were produced by a collision of accelerated electrons to positrons through the the Y(4S) resonance, and confirmed that the amount of the violation matches to the Kobayashi-Maskawa theory prediction. To make the verification more concrete, we further carried out more precise refinements of the Kobayashi-Maskawa theory parameters from several aspects using much larger data samples, and found most results matches to the theoretical prediction. While the great success of the Standard Model (SM) comprising the Kobayashi-Maskawa and other theories, we expect extensions of the SM should exist around 1TeV energy scale. In Belle, we already observed several implications of the new physics beyond the SM: difference in CP violations between B0 and B+, unexpectedly large D0-D0bar mixing, larger branching fraction of B->tau,nu than prediction, etc. To hunt for a new physics, an energy frontier experiment, ATLAS/CMS, has started in CERN; and a luminosity frontier experiment, Belle II, will start in KEK in 2015. These two frontier experiments are expected to elucidate the new physics complementarily; ATLAS/CMS directly detect new particles (SUSY?) with its energetic accelerator, while Belle II investigates their interactions precisely with the enormous number of clean e+ e- collisions. In Belle II, we access to the new physics through heavy particles that virtually show up in a B-meson decay diagram. In this sense, b->s,q,qbar, b->s,gamma, b->d,gamma, and B->tau,nu, will be key physics channels of Belle II. Research and development (R&D) of the Belle II detector have already started during the Belle operation. For example, R&D of the Belle-II data-acquisition system (DAQ) has started 10 years ago, and now the Belle-II DAQ will be one of the most promising system in our experiment. For other detectors, for example, the silicon vertex detector (SVD), which is to locate B-decay position precisely, is under hard development involving IPMU in hardware and in software, because of its important role to reduce the B-decay position resolution, which directly affects the precision of CP-violating parameter measurements of the decays listed above. |
| Seminar Video: | [VIDEO] |
