Joint Particle Seminar: George W. S. Hou (National Taiwan University)
| Description: |
Speaker: George W. S. Hou (National Taiwan University)
Title: CP Violation for the Heaven and the Earth --- The 4th Generation
Abstract: Kobayashi and Maskawa received 1/2 the 2008 Nobel prize for their mechanism of CP violation. This Standard Model of CPV, however, falls short by at least 10^-10 from what is needed to satisfy the Sakharov conditions for the absence of antimatter in our Universe. A large and unexpected difference in direct CPV between charged and neutral B -> Kpi decays, observed by Belle and BaBar, offers a possible clue for beyond SM source of CPV, but it is not free from hadronic uncertainties. From the insight of non-decoupling of heavy chiral quarks in Z penguin and box diagram loops, we have built up the case for a possible 4th generation source, predicting that sin2Phi_Bs in Bs -> J/psi phi should be large and negative, which is in remarkable agreement with recent hints from the Tevatron. If the current central value stays, the Tevatron could observe sin2Phi_Bs by 2010(11), and there will be no hadronic uncertainty. Recent updates on the forward-backward asymmetry in B -> K*l+l- by the B factories are also tantalizing. What may be the most astounding is that, having a 4th generation allows the CPV relevant for the Universe to jump by a factor of 10^15, and may even suffice for the Sakharov condition. It is even possible that electroweak symmetry breaking itself arises through the strong Yukawa couplings of the 4th generation quarks. We outline a direct search program for the 4th generation at the LHC (CMS in particular), aimed for early data. We should learn the answer in 3-5 years. This talk will present both experimental and phenomenological results. |
| Location: |
FRH 4135 |
| Date: |
Thursday, November 12, 2009 |
| Time: |
2:00pm-3:00pm PST |
| Duration: |
1 hour |
| Access: |
Public |
| Created by: |
Public Seminars ( by seminar administrator ) |
| Updated: |
Saturday, November 14, 2009 8:08am PST |
|
