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SuperB

SuperB.     . US Participation in the INFN Super Flavor Factory. David Hitlin P5 Meeting - SLAC February 21, 2008. The physics objectives of Super B. Requires a polarized electron beam.

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SuperB

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  1. SuperB  US Participation in the INFN Super Flavor Factory David Hitlin P5 Meeting - SLAC February 21, 2008

  2. The physics objectives of SuperB Requires a polarized electron beam There are, of course, a very large number of other measurements in weak decay flavor physics and in QCD that can be made for the first time or greatly improved • To study rare t, b and c decays with sufficientsensitivity to isolate evidence for physicsbeyond the Standard Model • Find charged lepton flavor violation in t decays and study it • Search for CP violation in t production and decay andmeasure the t anomalous magnetic moment • Precisely measure CP-violating asymmetries in penguin-dominated B decays to search for new physics effects • Measure x and y in mixing, and search for CP violation • Search for new physics effects on branching fractions and kinematic distributions in rare decay processes David Hitlin P5 Meeting - SLAC February 21, 2008 2

  3. David Hitlin P5 Meeting - SLAC February 21, 2008

  4. A conversation between SuperB, LHC and ILC • When evidence is found for New Physics at the LHC, attention will turn to understanding the details • Is it SUSY? What type of symmetry breaking? • Is it extra dimensions? Are they warped? • The ILC will eventually sharpen the picture by, for example, measuring slepton masses • SuperB will be crucial to an understanding of the flavor sector of any type of new physics • Is there charged lepton flavor violation? • Are there new CP phases ? • Is there a charged Higgs ? • Is there minimal flavor violation in the (s)quark sector? David Hitlin P5 Meeting - SLAC February 21, 2008

  5. Lepton flavor violation (LFV) • Lepton flavor violation is unobservably small in the Standard Model • Neutrino mixing proves that there is neutral LFV • The next natural question is whether there ischarged LFV? • Will the neutrino pattern be repeated? • If so, then LFV will be largest in 32 transitions • Best bets: David Hitlin P5 Meeting - SLAC February 21, 2008

  6. Charged lepton flavor violation in t decays SuperBsensitivity For 75 ab-1 David Hitlin P5 Meeting - SLAC February 21, 2008

  7. Sensitivity to models of LFV Goto, et al. arXiv:0711.2935v2 David Hitlin P5 Meeting - SLAC February 21, 2008

  8. Polarized t’s can probe the chiral structure of LFV Flipping the helicity of the polarizedelectron beam allows us to determine the chiral structureof dimension 6 four fermionlepton flavor-violating couplings Dassinger, Feldmann, Mannel, and Turczyk JHEP 0710:039,2007; [See also Matsuzaki and SandaarXiv:0711.0792 [hep-ph] David Hitlin SLUO Meeting February 7, 2008

  9. Polarization at SuperB • The SuperB design includes a polarized electron beam • SuperKEKB does not, and cannot, have a polarized beam • Spins must be vertical in the ring  spin rotators at the IP • Solenoid spin rotators appear best • 36.6 Tesla-meters for 90 spin rotation in the LER e.g. 2.5 Tesla x14.66 meters with 30x106 ampere-turns • Expected longitudinal polarization at the IP: 87%(injection) x 97%(ring)=85%(effective) David Hitlin P5 Meeting - SLAC February 21, 2008

  10. New CP-violating phases in penguin modes SuperB LHC squark mass matrix (d sector) g ~ W-H--0 g, ~ ~ ~ ~ ~ ~ b u,c,t s b u,c,t s b u,c,t s b d,s,b s David Hitlin P5 Meeting - SLAC February 21, 2008

  11. Sensitivity extends to high mass scales New Physics contribution (2-3 transition) ~ MSSM + generic softSUSY breaking terms g In the red regions the d are measured with a significance >3s away from zero ~ ~ b s s b 1 10-1 10-2 In this case the main constraints are bsg = (0.026 ± 0.005) ACP(bsg)) Arg(d23)LR=(44.5± 2.6)o 1 10 1 TeV ACP magenta B(sg) green B(sll) cyan All constr. blue David Hitlin P5 Meeting - SLAC February 21, 2008

  12. The pattern of deviations from SM values is diagnostic David Hitlin P5 Meeting - SLAC February 21, 2008

  13. How do you gather the data sample? y • Access to new physics effects in the flavor sector requires a datasample 100x the total existing BABAR + Belle sample and therefore an asymmetric e+e-collider with ~100x current luminosity • There are at least two different approaches: • Increase the current and number of bunches: SuperPEP-II, SuperKEKB • High bunch charge, small b, coherent synchrotron radiation, heating, background and total power issues • Decrease the emittance and beam size at the IP: SuperB • Low emittance rings, à la ILC damping rings,with collisions of strongly focused beams at the IP with a large Piwinski angle David Hitlin P5 Meeting - SLAC February 21, 2008

  14. The SuperB approach to high luminosity – P. Raimondi • Low emittance rings, à la ILC damping rings • Focus the beams strongly at the IP with a large Piwinski angle • Beam current and wallplug power < PEP-II • Ultra-low emittance – achieved at ATF2 • Very small band spot sizes at the IP – demag achieved at FFTB • Large crossing angle – achieved at KEKB • “Crab Waist” scheme – being tested at DAfNE now • Small collision area • Can achieve lowerb • No parasitic crossings • Reduce effect of synchrobetatron resonances due to crossing angle David Hitlin P5 Meeting - SLAC February 21, 2008

  15. Comparison of SuperB and SuperKEKB IP beam distributions forSuperB IP beam distributions for SuperKEKB David Hitlin P5 Meeting - SLAC February 21, 2008

  16. SuperB luminosity profile Peak luminosity can beupgraded to 2.5x1036(conservatively) Peak Integrated 160 ab-1 in ten years ~100 x combinedBABAR+Belle data sample David Hitlin P5 Meeting - SLAC February 21, 2008

  17. An upgrade of BABAR works well at SuperB Since currents are in the PEP-II range, a detector upgrade is straightforward - R&D on SuperB upgrade components is underway David Hitlin P5 Meeting - SLAC February 21, 2008

  18. The SuperB location on the Tor Vergata campus DAfNE David Hitlin P5 Meeting - SLAC February 21, 2008

  19. 100m SuperB footprint at Tor Vergata SuperB Ring ( circumference 1800m) SPARX FEL SuperB Injector (~ 400m) Roman Villa SuperB Main Building David Hitlin P5 Meeting - SLAC February 21, 2008

  20. SuperB uses many PEP-II components Quadrupoles Dipoles + RF (cavities, klystrons, .....) + vacuum components + accelerator expertise + BABAR as the foundation of an upgraded detector David Hitlin P5 Meeting - SLAC February 21, 2008

  21. How much will SuperB cost? From the SuperB CDR* Value of reusable itemsfrom PEP-II and BABAR Disassembly, crating, refurbishment andshipping costs areincluded in project costs *In the SuperB CDR costs were presented “ILC-style”, with labor in man-months, M&S in €. This table translates costs into US accounting and converts to $. David Hitlin P5 Meeting - SLAC February 21, 2008

  22. The level of US participation in SuperB • The US program has a unique opportunity, in a time of scarceresources, to make a highly leveraged investment in an important new project and thus to take a very significant role • There are both accelerator and detector/physics aspects • Accelerator • SLAC’s expertise in high current, high luminosity colliders is crucial • Detector/Physics: • 30 Pi’s from 18 US and 4 Canadian institutions have expressedinterest in SuperB in a letter to the SLAC PPA Division • We expect this interest to grow • In the TDR phase: 50-75 people, including postdocs/students • In the construction and physics phase: ~150 people • The SuperB meeting in Elba (May 31-June 3) will initiate collaboration-forming activities David Hitlin P5 Meeting - SLAC February 21, 2008

  23. What does US SuperB involvement entail? • The SuperB design uses many PEP-II components • Recognizing that there is internal competition for some of these items, a DOE HEP contribution of PEP-II magnets, RF and vacuum components, as well as of BABAR, as the basis for a detector upgrade, to SuperB would give the US a central position in a new high quality, high visibility project, for very little additional capital investment • SLAC would then be the natural center for US SuperB activities, in a role that only a national lab can play • Accelerator design and some component construction • Detector design and system construction • Physics: computing and analysis • There are different possible levels of participation David Hitlin P5 Meeting - SLAC February 21, 2008

  24. US participation levels David Hitlin P5 Meeting - SLAC February 21, 2008

  25. Why isn’t the SuperB crew interested in SuperKEKB? • This question is often asked; let’s address it directly • It is universally accepted that an e+e- data sample of 75ab-1 or more is required to confront the issue of New Physics effects in B, D and t decay • SuperB produces, at 1036, 15ab-1/Snowmass year, starting in ~2015 • SuperKEKB produces, at 2 (or 1) x1035, 1ab-1/running year, starting in ~2014, with an upgrade path that reaches 8 (or 4?) x1035 in 2027 • SuperB, with a polarized electron beam, produces polarized t leptons, opening an entirely new realm of exploration in lepton flavor physics • The SuperB low emittance, low current, design presents tractable detector and background problems, and affordable operating costs • These factors have convinced us that SuperB presents the most viablee+e-option to confront the question of flavor physics in the LHC era David Hitlin P5 Meeting - SLAC February 21, 2008

  26. But it’s a green field site • Building SuperB at an existing laboratory would certainly be easier • SLAC: upgrade PEP-II • FNAL: in the Tevatron tunnel, morphing into the ILC damping rings • KEK: see previous slide • CERN: ISR tunnel circumference is too small • DESY: PETRA tunnel • Building SuperB at Tor Vergata, as an international enterprise, is feasible and even exciting • Proximity to Frascati - INFN is in the process of establishing aSuperB Project Office at Frascati • Participation of accelerator experts from other labs is crucial to success • The Lazio regional government appears interested in funding the tunnel • The innovative collider design uses many PEP-II components • Tunneling for the SPARX FEL on the site will begin within months David Hitlin P5 Meeting - SLAC February 21, 2008

  27. Conclusions • SuperB presents an exciting opportunity for the US program • A broad and deep physics program: results will be crucial to understanding new physics uncovered at the LHC • Leverage: in a time of shortage of investment capital, gives the US a major role in a European project for a relatively small investment • Timing: • SuperB provides an opportunity to retain the impressive capability of the US accelerator community by having them contribute to an innovative new e+e- collider • SuperB provides an opportunity for the very productive BABAR-CLEO-BES community to participate in a state-of-the art detector upgrade that will be producing physics in the middle of the next decade David Hitlin P5 Meeting - SLAC February 21, 2008

  28. Backup slides David Hitlin P5 Meeting - SLAC February 21, 2008

  29. Schedule Four year construction, preceded by 2-3 yearsof design and prototyping, which overlaps organizational and funding activities David Hitlin P5 Meeting - SLAC February 21, 2008

  30. David Hitlin P5 Meeting - SLAC February 21, 2008

  31. David Hitlin P5 Meeting - SLAC February 21, 2008

  32. Crab crossing experience at KEKB • Lower bunch current product makes luminosity twice of the crossing-angle collision. • However, slope of the specific luminosity is NOT understood well. • If the reason is an electron cloud, no problem after upgrade. • If luminosity is limited by something else, we must investigate it. • Synchro-beta resonance ? • Other nonlinear effects ? Onishi at Atami Workshop 1.7x1035 ex=24 nm Crab crossing 49 sp nb=50 what is a slope ? Crab crossing 3.06 sp nb=1548 22 mrad crossing 3.5 sp nb=1388 9.4/4.1 A nb=5018 David Hitlin P5 Meeting - SLAC February 21, 2008

  33. A Super B Factory is a DNA chip for New Physics David Hitlin P5 Meeting - SLAC February 21, 2008

  34. Project X flavor physics • to e conversion • Rme< 2x10-17 • in a generation12 transition • MECO/Mu2e are large,expensive experiments • Sensitivity with respect to meg? • Is this more or lessinteresting than 23 ? David Hitlin P5 Meeting - SLAC February 21, 2008

  35. Signers of SuperB letter to PPA – 10/07 David Hitlin P5 Meeting - SLAC February 21, 2008

  36. Fermilab Steering Group report – Appendix E David Hitlin P5 Meeting - SLAC February 21, 2008

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