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B Factories : a truly remarkable story of competition and collaboration

B Factories : a truly remarkable story of competition and collaboration. Guy Wormser LAL Orsay CNRS/IN2P3 and Université Paris Sud. Talk Outline. Main objective : advertise the parallel session on these topics planned at 5pm in Room 404 A word about B factories Physics Program

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B Factories : a truly remarkable story of competition and collaboration

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  1. B Factories: a trulyremarkable story of competition and collaboration Guy Wormser LAL Orsay CNRS/IN2P3 and Université Paris Sud

  2. Talk Outline • Main objective : advertise the parallel session on these topics planned at 5pm in Room 404 • A word about B factories Physics Program • Historical reminder : PEP-II and KEKB, BABAR and BELLE • Presentation of the two present projects SuperB and SuperKEKB • Conclusion

  3. Parallel Session ProgramB factories, competition and collaborationRoom 404 5 pm • Introduction and presentation of SuperB Project GW • Presentation of the SuperKEKB project John Flanagan (KEK) • BABAR-BELLE, the competition Yoshihide Sakai (KEK) • BABAR-BELLE the collaboration, GW • Discussion : Way towards the future

  4. What is B Physics • B mesons contain a quark b • Studies of the tiny difference between matter and anti matter gives direct access to the fundamental parameters of the Standard Model (the CKM matrix) • Billions of B and anti B mesons were studied at the B factories to search for such effects and constraint the Standard Model • The conclusion is « The mechanism present in the SM to describe CP violation is validated by data ». Two consequences : • A well deserved Nobel prize in 2008 to Prof. Kobayashi and Maskawa • Paradoxical situation since we know this mechanism must be broken at some point and that new physics will manifest in this area

  5. In SM Today SuperB+Lattice improvements r = 0.163 ± 0.028 h = 0.344± 0.016 Improving CKM is crucial to look for NP r = ± 0.0028 h = ± 0.0024

  6. B Physics Achievements b→d D0-D0mixing Exotic hadrons X(3872) B→tn CP violation B→K*ℓ+ℓ− 5.3 Mbc (GeV/c2)

  7. Historical reminder • It started with collaboration: 1981 Bigi and Sanda Notes on the Observability of CP Violations in B Decays • 1987 P. Oddone propose the concept of asymmetric e+e- colliders at the Y(4S) energies • 1993-1994 PEP-II/BABAR approved in California with strong European component, KEKB/BELLE approved in Japan with US and a small european component

  8. The machines • Very hard challenge: beat the best machine of the time (CESR-Cornell) by a factor 100 ! • Unknown territory : asymmetric e+e- colliders • Energy transparency theorems • Competition allowed the choice of agressive and complementary solutions • Large crossing angle and small beam sizes at KEK • Very large currents at PEP-II • Competition made the machines turn to happen within a week (in May-June 1999)! • Remarkable short time for such projects • Competition was one of the major drivers into pushing the performances to ultimate limits in terms of peak and avergae luminosity • Remarkable success of « topping off » mode

  9. The PEP-II rings

  10. KEKB = Asymmetric Double-Ring Collider for B-Physics8 GeV Electron + 3.5 GeV Positron Superconducting cavities (HER) Belle detector e- KEKB B-Factory e+ ARES copper cavities (HER) ARES copper cavities (LER) TRISTAN tunnel 8 GeV e- 3.5 GeV e+ Linac e+ target 1989: Design work started. 1994: Approval of the budget, construction started. June 1995: KEKB Design Report Sep. 1997: Commissioning of the injector Linac started. Dec. 1998: First beam at HER. Jan. 1999: First beam at LER. May 1999: Belle roll-in. June 1999: First event at Belle. Apr. 2001: World record of the luminosity, 3.4 /nb/s. Oct. 2002: World record of the integrated luminosity, 100 /fb. May 2003: Exceeded the design luminosity, 10 /nb/s. Feb. 2007: Crab crossing started. May 2009: Exceeded 21 /nb/s, twice the design luminosity. Nov. 2009: Exceeded the integrated luminosity, 1000 /fb. … continues updating self records …

  11. Collaboration to reachultimate performances • Joint workshops on several machines issues: • Electron cloud remediation • Background remediation • Machine optics • Feedbacks • Cross-participation to machine advisory bodies • Visits, conferences,…

  12. Factor 100 achieved!

  13. The SuperB projects • History in some sense repeats itself; need to build new machines performing 50 times than present ones! • Common physics goals for « Europe » and « Japan » projects with two important exceptions: • SuperB will have polarised electron beam • SuperB foressees to run for some periods of time at Charm and tau threshold at 10**35 luminosity • Key breakthrough is « Crab waist » scheme proposed by P. Raimondi from LNF Frascati. • KEK is proposing a 350 M€ KEKB upgrade • INFN is proposing a 420 M€ new project based either at Frascati or in Tor Vergata University

  14. Flavour physics in the LHC era The main objective is to unravel the flavor structure of the New Physics and the mechanisms causing its specific pattern Very good sensitivity to NP thru CP violation asymmetries and rare decays Double-prong attack on the quark and lepton sectors 16 16

  15. WHAT IS REALLY STRANGE IS THAT WE DID NOT SEE ANYTHING…. With masses of New Particles at few hundred GeV effects on measurable quantities should be important Leff <~ 1TeV + flavour-mixing protected by additional symmetries (as MFV) Couplings can be still large if Leff > 1..10..TeV Matching the naturalness arguments

  16. Y. Ohnishi / KEK

  17. Belle II in comparison with Belle SVD: 4 DSSD lyrsg 2 DEPFET lyrs + 4 DSSD lyrs CDC: small cell, long lever arm ACC+TOF g TOP+A-RICH ECL: waveform sampling, pure CsI for end-caps KLM: RPC g Scintillator +SiPM (end-caps) Parameters are preliminary

  18. Detector Layout – Reuse parts of Babar (or Belle) BASELINE OPTION 28 Nov,2008 Marcello A.Giorgi 20 Warwick April 14,2009 Marcello A. Giorgi 20

  19. Beams distribution at IP E. Paoloni Without Crab-sextupoles Crab sextupoles OFF waist line is orthogonal to the axis of one bunch Crab sextupoles ON With Crab-sextupoles waist moves to the axis of other beam All particles from both beams collide in the minimum by region, with a net luminosity gain

  20. Crab on/off Specific Luminosity vs Current Product Lifetime limit Crab on/off Luminosity vs Current Product

  21. Political status • Both projects are climbing up the stairs towards governemental approval • Steady (but slow ) progress • Both projects have received good level of international support and some extent of stimulus package money to perform initial studies • In Italy , 3 levels (INFN, Ministry of Research, Ministry of Finance) and 3 steps each time (proposal, discussion, approval). We are at Step 8 out of 9! Also waiting for imminent publication of a National Research Infrastructure Plan by the Ministry of Research • In Japan, publication last week of a « bottom up » Roadmap to be reviewed, prioritized and financed around July. SuperKEKB among the 3 HEP accelerator-based projects • 6 Oku-Yen released to start construction of a damping ring for KEKB upgrade

  22. What next • Two parallel efforts to get a project approved by its national authorities • What happens in case 0 or 1 project is accepted is relatively clear! • What happens if both projects are accepted • History showed the benefits of collaboration/competition model • Can the community afford two such projects in tems of money or personnel (more tricky) • Global vs regional • Come to the parallel session to discuss these issues!

  23. Conclusion • The construction, operation and physics exploitation of the 2 B-Factories in SLAC and KEK turned out to be a huge scientific success largely based on the competition-collaboration model! • Now, science calls for the next generation of such machines with performances improved again by 2 orders of magnitude! • KEK and INFN (together with their partners) are proposing two such projects to their respective government (projects in the 500 M€ class). Both projects could be accepted relatively soon • Will history repeat itself? To know more, come to the parallel session at 5 pm in Room 404!

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