北航课件-BelleII.ppt

* B factories and hadron spectroscopy B factories have found most of the still missing pieces in bottomonium and charmonium spectra. Belle, Babar, BES-III and LHCb are studying a plethora of new states, the so called XYZ mesons, which require a spectroscopy with new degrees of freedom (tetraquarks, molecules, hybrids). Many new questions arose from unexpected states near the open charm/beauty thresholds. A lot more to be explored with considerably larger data sets! 8 out of 14 most cited Belle papers are spectroscopy related To be updated Book: The Physics of the B factories ● Released on 2013.7.8 ● Efforts from both of BaBar and Belle ● More than four years to finish it ! arXiv:1406.6311 To be published in EPJC Book: 910 pages 2008 诺贝尔奖写序 Next generation: Super B factories ? Looking for New Physics Need much more data (almost two orders!) Super B factory: also an excellent tool for studies of exotic hadrons A new feature: very strong competition from LHCb and BESIII Still, e+e- machines running at (or near) Y(4s) will have considerable advantages in several classes of measurements, and will be complementary in many more What next? * ? Physics at Super B Factory, arXiv:1002.5012 (Belle II) ? SuperB Progress Reports: Physics, arXiv:1008.1541 (SuperB) Need O(100x) more data ?Next generation B-factories 40 times higher luminosity 8 x1035 KEKB SuperKEKB PEP-II How to do it? upgrade the existing KEKB and Belle facility KEKB ? SuperKEKB Belle ? Belle II e+ source Ares RF cavity Belle detector Peak luminosity (WR!) : 2. 1 x 1034 cm-2s-1 =2x design value SCC RF(HER)? ARES(LER)? The KEKB Collider e- (8 GeV) on e+(3.5 GeV) √s ≈ mΥ(4S) Lorentz boost: βγ=0.425 22 mrad crossing angle First physics run on June 2, 1999 Last physics run on June 30, 2010 Lpeak = 2.1x1034/cm2/s L 1ab-1 Fantastic performance far beyond design values! Collision with very small spot-size beams Invented by Pantaleo Raimondi for SuperB How big is a nano-beam ? - Ho