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UK-CDF

UK-CDF. Ronan McNulty (Liverpool) on behalf of Glasgow, Liverpool, London, Oxford. Tevatron Operations Hardware Layer00 SVX Software Silicon Monitoring and Alignment Level 3 Trigger CDF Database Computing. Physics Analyses B physics Electroweak Searches Comments & Conclusions.

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UK-CDF

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  1. UK-CDF Ronan McNulty (Liverpool) on behalf of Glasgow, Liverpool, London, Oxford

  2. Tevatron Operations Hardware Layer00 SVX Software Silicon Monitoring and Alignment Level 3 Trigger CDF Database Computing Physics Analyses B physics Electroweak Searches Comments & Conclusions Overview

  3. Commissioning Run 7 fills: Oct 8th – Nov 4th Max lumi: 4x1029cm-2/s with 36x36 bunches 57.6nb-1 integ. lumi. All detectors installed bar Silicon. 6% proto-type instead. Level 1,2 & 3 triggers Full DAQ Run II April 3rd 2001  LHC startup Max lumi: 7.9x1030cm-2/s 7.2pb-1 integ. lumi. Expect 2000pb-1 CDF essentially complete Level 1 (2) 3 triggers Physics quality data Tevatron Operations

  4. Layer00 is the silicon detector closest to the beampipe. R=1.6cm UK designed & purchased the silicon. Designed and constructed the two 50cm long carbon fibre support structure and cooling. Irradiated and tested kapton cables Performed cooling studies Size of Beampipe Layer 00 Wide plaquettes Sit here Narrow plaquettes Cooling channel Carbon fibre prototype

  5. Hybrid Layer 00 construction Assembly jig Wide silicon mounted here Narrow silicon mounted

  6. Layer00 Performance 1/6 of Layer00 taking data (due to power supply delays) Tracks observed in silicon Charge deposition in silicon

  7. SVX Two wedges of SVX Implemented for Commissioning Run One of Three Silicon Barrels installed for Run II.

  8. SVX Testing

  9. Performance of SVX Correlation of charge deposited on n and p sides, for data taken with a ruthenium source

  10. UK first to see beam profile Combined efforts of silicon expertise, database (pedestal update), and tracking algorithms led to first observation of the beam during Commissioning Run Silicon Layers Beampipe Overlay of many events with pT>100MeV cm Residuals from Si hits to circle fit

  11. Comprehensive monitoring tool Online: for rapid reaction to problems Offline: for detailed studies and record of performance over time Implementation: Define quantities Create histograms Intuitive GUI Silicon Monitoring

  12. Barrel 0 Barrel 1 Barrel 2 Rf hits Rf hits on tracks R v z for hits on tracks

  13. Silicon Alignment Alignment vital for b tagging, B lifetimes, oscillations, CP violation, and searches Perfect Alignment s = 14mm Impact Parameter (cm) After s=15mm Before s=40mm Impact Parameter (cm) Impact Parameter (cm)

  14. Level 3 Trigger

  15. Level 3 Trigger • Software Trigger (In 500Hz; out 75Hz) • Fast event reconstruction on 250 CPUs. • Operating since commissioning run • UK coordination and 24 hour support • Automated system for code validation • Regional tracking algorithms for full offline reconstruction in selected detector regions

  16. The CDF Database • UK responsible for delivering the CDF database, online and offline. • Acquire, store, provide information about the data and running conditions. • Online: real time storage from hardware, run control, trigger, monitoring, calibration • Offline: deliver to reconstruction and physics analysis. • Coordinate consultants, schema designers, computer system experts, users.

  17. The CDF Database 5 dbAdministrators • Start: structure insufficient for expected size and usage • Poll hardware and software experts • Implement new management structure • End: 30GB database created which handles 50,000 accesses/day. 99.8% up-time. • Prototype database export system setup and in test between FNAL and UK. 7 C++/Oracle physicist 40 Application programmers 500 Users Tools

  18. Coherent UK strategy on computing >1Petabyte of data £1.8m grant from JIF 4/5 for high-speed, high-volume disk 1/5 for networking Committed half so far Universities & RAL: 8-way SMP server with fibre channel to 1TB RAID Universities at FNAL: 8 dual-processor PCs FNAL: 10TB RAID Computing Direct Contribution from UK to CDF

  19. Improve performance of Tevatron Several 10% improvements possible Request for effort Optimise lithium lens design (p collection) Model production and propagation Create visualisation tool for machine physicists Three UK technicians helping (travel paid by FNAL) One UK student (funded by FNAL) Accelerator Work

  20. Physics Analyses • B physics: Lifetimes and Oscillations • Electroweak Physics • Searches: SUSY and Higgs

  21. B lifetimes • First measurements which CDF will perform in b sector • Necessary step towards oscillation • (Test of alignment, tracking, tagging.) • Best measurement of Bs0, Lb. (Unique) HQET: t(B+ )/ t (B0 )=1.05 t( Bs0)/ t (B0 )=1.00 t( Lb)/ t (B0 )=0.9 to 1.0 Experiment: t( Lb)/ t (B0 ) is 0.78+-.04

  22. B lifetimes

  23. B lifetime Millions of B mesons have already been produced in RunII. Need to trigger and identify relevant decays. Leptons ‘easy’; hadrons difficult Run I data: UK thesis topic Run II data: tracks with Silicon hits Look for J/y mm Search for B+J/y K+

  24. Bs oscillations • Lifetime measurements: prelude to oscillations • For B mesons, Flavour eigenstates weak eigenstates • So B0B0 • Mixing parameter: x = Dm/G • LEP/Barbar: xd = 0.73 To date: xs > 14.6 Tevatron unique • Usually measure by oscillating exponential; UK has developed new complementary method PB(t)  e-Gt(1+cos(Dm t))

  25. B oscillations • Dm  DG = f (tH, tL ) • Separate eigenstates and measure each lifetime • BS DS+ DS- (CP even) Work continuing in triggering on these difficult hadronic modes (track/vertex/reconstuct) • BS J/y f (CP even&odd) Different angular distribution for mm allow separation of CP even and odd states • BS J/y h (CP odd)

  26. B oscillations Search for BS J/y h. UK Thesis with Run 1 data Br.(BS J/y h)<8.75 x 10-4 at 90% c.l. (Prelim)

  27. Introduce new W and Z simulations to CDF Calculate systematic uncertainty on W mass from higher orders. Conclude (2fb-1) W mass to 30MeV W width to 40MeV Studying muon and electron identification Electroweak Physics

  28. Electroweak Physics

  29. Electroweak Physics Z  mm candidate

  30. Studying lepton spectra for sensitivity to different SUSY models (eg. gluino pairs) Builds on electron/muon identification Specific search for chargino decays c+  c02 ln c02 c01 l l 3 leptons often enriched in taus SUSY

  31. Higgs Higgs search will be highlight of Run II for CDF/D0. Standard searches may exclude but not discover Higgs to 180GeV

  32. Higgs • Largest production mode is gg  H bb • …. but QCD background enormous • We can reconstruct bb with 10-15 GeV. • …. Suppose we could reconstruct with 200 MeV

  33. CDF 55m Higgs Look in diffractive mode pp pHp Reconstuct from missing mass of pp system Large theoretical uncertainties exist as discussed at IPPP Durham last week. Theoretical & Experimental clarification required before proceeding to CDF approval or build.

  34. Higgs

  35. Glasgow (2.6 FTE) S. d’Auria P. Bussey R. St.Denis S. Thomson 5 students Liverpool (5.9 FTE) P. Booth B. Heinemann M. Houlden B. King S. Marti R. McNulty T. Shears A. Taffard 2 students Oxford (4.7 FTE) F. Azfar T. Huffman J. Loken L. Lyons J. Rademacker A. Reichold P. Renton D. Waters 4 students UCL (2.1 FTE) M. Lancaster R. Snihur D. Waters 3 students UK CDF Personnel

  36. Conclusions (I) • Relativity small number of physicists: 15.3 FTE + 14 students • High profile on experiment of 500 people • Very attractive to students and postdocs • Value for money • Limited funding is having an impact on recruitment, profile and physics • Further to continual maintenance, we need to exploit out investment by producing physics.

  37. Conclusions (II) • UK have delivered major components of CDF: Layer00, Level 3 Trigger, Database. • UK coordinate/are responsible for: Database, Level 3, Silicon Monitoring, Alignment • Understanding Detector: Silicon, Tracking, Muons, Electrons • Physics Analysis underway: B physics, Electroweak, Searches • Coherent UK hardware/software effort with common data model (JIF) & common physics goals.

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