1 / 67

Heavy Fermion Physics at Super Flavour Factories

Portorož 2011 The Role of Heavy Fermions in Fundamental Physics April 11 - 14 2011, Portorož, Slovenia. Heavy Fermion Physics at Super Flavour Factories. Peter Kri ž an University of Ljubljana and J. Stefan Institute. “Jožef Stefan” Institute. University

macw
Download Presentation

Heavy Fermion Physics at Super Flavour Factories

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Portorož 2011 The Role of Heavy Fermions in Fundamental Physics April 11 - 14 2011, Portorož, Slovenia Heavy Fermion Physics at Super Flavour Factories Peter Križan University of Ljubljana and J. Stefan Institute “Jožef Stefan” Institute University of Ljubljana

  2. Contents • Physics case for a Super B factory • SuperKEKB/Belle-II@KEK and SuperB@Italy • Accellerators • Detectors • Status and prospects of the projects • Tau/charm factories

  3. _ 535 M BB pairs B0 tag _ B0 tag B factories: CP violation in the B system CP violation in B system: from the discovery (2001) to a precision measurement (2006) sin2f1/sin2b from bccs Constraints from measurements of angles and sides of the unitarity triangle  Remarkable agreement World average 2008: sin2f1= 0.681±0.025 _

  4. B factories: a success story • Measurements of CKM matrix elements and angles of the unitarity triangle • Observation of direct CP violation in B decays • Measurements of rare decay modes (e.g., Btn, Dtn) • bs transitions: probe for new sources of CPV and constraints from the bsg branching fraction • Forward-backward asymmetry(AFB) in bsl+l-has become a powerfull tool to search for physics beyond SM. • Observation of D mixing • Searches for rare t decays • Observation of new hadrons

  5. Fantastic performance much beyond design values!

  6. What next? B factories  is SM with CKM right? Next generation: Super B factories  in which way is the SM wrong? • Need much more data (two orders!) because the SM worked so well until now  Super B factory However: it will be a different world in four years, there will be serious 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

  7. Power of e+e-, example: Full Reconstruction Method • Fully reconstruct one of the B’s to • Tag B flavor/charge • Determine B momentum • Exclude decay products of one B from further analysis Decays of interest BXu l n, BKn n BDtn, tn B e- (8GeV) e+(3.5GeV) Υ(4S) p B full reconstruction BDpetc. (0.1~0.3%)  Offline B meson beam! Powerful tool for B decays with neutrinos

  8. Event candidate B- t- nt

  9. Charged Higgs limits from B- t- nt b u W/H    limit on charged Higgs mass vs. tanb 50 ab-1 ~0.5 ab-1

  10. B→D(*)n Semileptonic decay sensitive to charged Higgs Ratio of t to m,e could be reduced/enhanced significantly c b   W/H T.Miki, T.Mimuta and M.Tanaka:hep-ph 0109244. Compared to B→tn • Smaller theoretical uncertainty of R(D) For B→tn, There is O(10%) fBuncertainty from lattice QCD • Large expected Br (Ulrich NierstearXiv:0801.4938.) • Differential distributions can be used to discriminate W+ and H+ • Sensitive to different vertex Bt n: H-b-u, BDtn: H-b-c • (LHC experiments sensitive to H-b-t)

  11. BDtn Exclusion plots for tanb and H+ mass for 5ab-1and 50ab-1

  12. BD*tn - similar constraints on H+ [PRL 99, 191807 (2007)] 535M BB Tag side B mass peaking background (D*-en) combinatorial background

  13. B →K(*)nn arXiv:1002.5012 B →Knn, B ~ 4∙10-6 B →K*nn, B ~ 6.8∙10-6 adopted from W. Altmannshofer et al., JHEP 0904, 022 (2009) Theory present exclusion limits SM: penguin+box Look for departure from the expected value  information on couplings CnR and CnLcompared to (CnL)SM Again: fully reconstruct one of the B mesons, look for signal (+nothing else) in the rest of the event. 50 ab-1 arXiv:1008.1541 not possible @ LHCb

  14. CP violation in BKSp0g CP violation in BKSp0g decays: Search for right-handed currents B →K*g, B ~ 4.0∙10-5 dS ~0.2 (present)  ~a few % at 50 ab-1 5 ab-1 50 ab-1 adopted from HFAG not possible @ LHCb

  15. Charm mixing: expected sensitivities Mixing parameters HFAG c2 fit Belle II, 50 ab-1 1 s @ 50 ab-1 only KK/pp, Kp and Kspp projected sensitivities included

  16. Charm: expected sensitivities CPV parameters Belle II, 50 ab-1 1 s @ 50 ab-1 only KK/pp, Kp and Kspp projected sensitivities included

  17. t physics:LFV and New Physics tlg • SUSY + Seasaw • Large LFV • t3l,lh • Neutral Higgs mediated decay. • Important when MSUSY >> EW scale. Br(tmg)=O(10-7~9) • = Upper limits modelBr(t→mg) Br(t→lll ) mSUGRA+seesaw10-7 10-9 SUSY+SO(10)10-8 10-10 SM+seesaw10-9 10-10 Non-Universal Z’10-9 10-8 SUSY+Higgs10-10 10-7 Integ. Lum.（ ab-1） Reach of B factories Super B factories Integ. Lum.（ ab-1）

  18. B Physics @ Y(4S) Charm mixing and CP Charm FCNC Bs Physics @ Y(5S) t Physics M. Giorgi, ICHEP2010

  19. Physics with 50ab-1/ 75ab-1 Two publications: • Physics at Super B Factory (Belle II authors + guests) hep-ex > arXiv:1002.5012 • SuperB Progress Reports: Physics (SuperB authors + guests) hep-ex > arXiv:1008.1541

  20. Physics at a Super B Factory • There is a good chance to see new phenomena; • CPV in B decays from the new physics (non KM). • Lepton flavor violations in t decays. • They will help to diagnose (if found) or constrain (if not found) new physics models. • Btn, Dtn can probe the charged Higgs in large tanb region. • Physics motivation is independent of LHC. • If LHC finds NP, precision flavour physics is compulsory. • If LHC finds no NP, high statistics B/t decays would be a unique way to search for the >TeV scale physics (=TeV scale in case of MFV). There are many more topics: CPV in charm, new hadrons, …

  21. Accelerators

  22. Need O(100x) more data Next generationB-factories SuperKEKB+SuperB 1036 40 times higher luminosity KEKB PEP-II

  23. How to do it?  upgrade KEKB and Belle

  24. Belle detector Ares RF cavity e+ source The KEKB Collider & Belle Detector • e- (8 GeV)on e+(3.5 GeV) • √s ≈ mΥ(4S) • Lorentz boost: βγ=0.425 • 22 mrad crossing angle • Operating since 1999 SCC RF(HER)‏ Peak luminosity (WR!) : 2. 1 x 1034 cm-2s-1 =2x design value ARES(LER)‏ First physics run on June 2, 1999 Last physics run on June 30, 2010 Lpeak = 2.1x1034/cm2/s L > 1ab-1

  25. The last beam abort of KEKB on June 30, 2010  Can start construction of SuperKEKB and Belle II

  26. Strategies for increasing luminosity - - • Smallerby* • (2) Increase beam currents • (3) Increase xy “Nano-Beam” scheme Collision with very small spot-size beams Invented by Pantaleo Raimondi for SuperB

  27. Machine design parameters • Small beam size & high current to increase luminosity • Large crossing angle • Change beam energiesto solve the problem of LER short lifetime

  28. KEKB to SuperKEKB Belle II Colliding bunches New IR e- 2.6 A New superconducting /permanent final focusing quads near the IP New beam pipe & bellows e+ 3.6 A Replace short dipoles with longer ones (LER) Add / modify RF systems for higher beam current Low emittance positrons to inject Positron source Damping ring Redesign the lattices of HER & LER to squeeze the emittance New positron target / capture section TiN-coated beam pipe with antechambers Low emittance gun Low emittance electrons to inject To get x40 higher luminosity

  29. How to do it? (2) • Construct a new tunnel in Italy • Move magnets from PEP-II • Move BaBar, upgrade

  30. Nano-beam collisions with crab waist Pantaleo Raimondi Crab waist scheme: successfully tested in the DAFNE ring

  31. Annecy SuperB Workshop Parameters for 1×1036 Lumi (max 4×1036 ) Tau/charm threshold running at 1035 • Baseline + • other 2 options: • Lower y-emittance • Higher currents • (twice bunches) • Baseline: • Higher emittance • due to IBS • Asymmetric beam • currents RF power includes SR and HOM M. Giorgi, ICHEP2010

  32. Interest of running at charm thresholdDecays of (3770)  D0D0 produce coherent (C=-1) pairs of D0’s. • 3 months of running will give 500fb-1: 50x BES-III • Precision charm mixing, • CPT Violation, rare decays, CPV using quantum correlations, decay constants, ... A. Bevan, Capri Workshop July 2010

  33. Polarized beam helps to reduce irreducible background in tau decays (e.g. tmg) 75 ab-1 arXiv:1008.1541v1 [hep-ex] B(tmg) 2 10-9 B(tmg) 1 10-9 B(teg) 2 10-9 B(teg) 1 10-9 Sensitivity improves at least by a factor 2. Equivalent to a factor 4 increase in luminosity. M. Giorgi, ICHEP2010

  34. LER HER Machine layout Polarization (80%) is understood and feasible. Parameter flexibility allows 1036 peak lumi without stressing limits! The operation of synchrotron lines and HEP operation seem to be compatible within the same machine.

  35. Detectors

  36. Requirements for the Belle II detector Critical issues at L= 8 x 1035/cm2/sec 4Higher background ( 10-20) 4Higher event rate ( 10) 4Require special features • radiation damage and occupancy • fake hits and pile-up noise in the EM - higher rate trigger, DAQ and computing • low pm identification f smm recon. eff. • hermeticity fn “reconstruction” Solutions: 4Replace inner layers of the vertex detector with a pixel detector. 4Replace inner part of the central tracker with a silicon strip detector. 4Better particle identification device 4Replace endcap calorimeter crystals 4Faster readout electronics and computing system. Very similar reasoning also for SuperB

  37. 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)

  38. DEPFET: http://aldebaran.hll.mpg.de/twiki/bin/view/DEPFET/WebHome Vertex Detector Beam Pipe r = 10mm DEPFET Layer 1 r = 14mm Layer 2 r = 22mm DSSD Layer 3 r = 38mm Layer 4 r = 80mm Layer 5 r = 115mm Layer 6 r = 140mm Mechanical mockup of pixel detector Prototype DEPFET pixel sensor and readout A prototype ladder using the first 6 inch DSSD from Hamamatsu has been assembled and tested.

  39. Expected performance Ks track p+ p- g g B vertex IP profile g Significant improvement in IP resolution! Pixel detector close to the beam pipe s[mm] Belle s[mm] BelleII’ BelleII 0 1.0 2.0 0 1.0 2.0 B decay point reconstruction with KS trajectory pbsin(q)5/2[GeV/c] pbsin(q)3/2[GeV/c] Significant improvement in dS(KSp0g) Less Coulomb scatterings Larger radial coverage of SVD

  40. Particle Identification Devices Endcap PID: Aerogel RICH (ARICH) Barrel PID: Time of Propagation Counter (TOP) Quartz radiator Focusing mirror Small expansion block Hamamatsu MCP-PMT (measure t, x and y) 200mm Cherenkov photon Aerogel radiator Aerogel radiator n~1.05 Hamamatsu HAPD + readout 200 Hamamatsu HAPD + new ASIC

  41. Barrel PID: Time of propagation (TOP) counter • Cherenkov ring imaging with precise time measurement. • Reconstruct angle from two coordinates and the time of propagation of the photon • Quartz radiator (2cm) • Photon detector (MCP-PMT)‏ • Good time resolution ~ 40 ps • Single photon sensitivityin 1.5

  42. Aerogel RICH (endcap PID) Test Beam setup Aerogel Clear Cherenkov image observed Hamamatsu HAPD Q.E. ~33% (recent good ones) Cherenkov angle distribution RICH with a novel “focusing” radiator – a two layer radiator Employ multiple layers with different refractive indices Cherenkov images from individual layers overlap on the photon detector. 6.6σp/K at 4GeV/c !

  43. SuperB Detector (with options) IFR Optimized layout. Plan to reuse yoke. Still need to resolve engineering questions. BEMC Inexpensive Veto device bringing 8-10% sensitivity improvements for Bt n. Low momentum PID via TOF? Technical Issues? 6Layer SVT L0 Striplets @ 1.6cm if background is acceptable as default. MAPS Option FPID Physics gains about 5% in BK(*)nn. Somewhat larger gains for higher multiplicities M. Giorgi, ICHEP2010

  44. Status of the projects

  45. Belle II Collaboration 13 countries/regions, 54 institutes 300 collaborators, >100 from Europe

  46. SuperKEKB/Belle II funding Status KEKB upgrade has been approved • 5.8 oku yen (~MUSD) for Damping Ring (FY2010) • 100 oku yen for machine -- Very Advanced Research Support Program (FY2010-2012) • Full approval by the Japanese government by December 2010; the project is in the JFY2011 budget as approved by the Japanese Diet end of March 2011 Several non-Japanese funding agencies have alsoalready allocated sizable funds for the upgrade. construction started!

  47. Construction Schedule of SuperKEKB/Belle II FY2009 FY2010 FY2011 FY2012 FY2013 FY2014 e+ new matching & L-band acc. Linac R&D Construction e+ beam commissioning RF-gun & laser system A1 gallery extension move to A1 Design study Commissioning at test stand e- beam commissioning Damping Ring Facilities Tunnel construction DR commissioning Building construction Components R&D, Design Mass Fabrication Installation Main Ring Facilities Building construction Components MR commissioning R&D, Design Mass Fabrication Installation BEAST II Belle II Detector Ad-hoc detector for MR commissioning R&D Mass Production Construction Belle roll-out in Dec. 2010 Installation (KLM) Installation (E-cap) Ready to Roll-in Installation (Barrel) Cosmic Ray Test

  48. Luminosity upgrade projection Milestone of SuperKEKB Plan: reach 50 ab-1 in 2020~2021 9 month/year 20 days/month Integrated Luminosity (ab-1) 5 ab-1in 2016 Commissioning starts mid of 2014 Peak Luminosity (cm-2s-1) Shutdown for upgrade Year

  49. KEKB/Belle status: official statement As is now well known, Japan suffered a terrible earthquake and tsunami onMarch 11,which has caused tremendous damage, especially in the Tohoku area. Fortunately,all KEK personnel and users are safe and accounted for. The injection linacdid suffer significant but manageable damage, and repairs are underway. The damage to the KEKB main rings appears to be less serious, though non-negligible. No serious damage has been reported so far at Belle. Further investigation is necessary. We would like to convey our deep appreciation to everyone for your generous expressions of concern and encouragement.

  50. KEKB/Belle status Fortunately enough: • KEKB stopped operation in July 2010, and was already to a large extent disassembled before the earthquake • Belle was rolled out to the parking position in December. We will check the functionality of the calorimeter in the next months (channel by channel...)

More Related