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The Tevatron’s Run 2 Physics Program

The Tevatron’s Run 2 Physics Program. Al Goshaw Duke University and Fermilab PHENO 2001 Madison May 8, 2001. Outline. Status of the Tevatron Run 2 start-up Accelerator D0 and CDF experiments Opportunities for Run 2 discoveries Some Run 1 physics highlights and Run 2 projections

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The Tevatron’s Run 2 Physics Program

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  1. The Tevatron’s Run 2Physics Program Al Goshaw Duke University and Fermilab PHENO 2001 Madison May 8, 2001

  2. Outline • Status of the Tevatron Run 2 start-up • Accelerator • D0 and CDF experiments • Opportunities for Run 2 discoveries • Some Run 1 physics highlights and Run 2 projections • W boson studies • Top quark program • B physics • Approach to Higgs search (details from Dave Rainwater) • SUSY, LED, … (talk by Carlos Wagner) • Summary A. Goshaw PHENO 2001

  3. Booster p source Main Injector and Recycler What’s New for Run 2?

  4. Tevatron Improvements Discovery of top, Bc, … 5x 1032cm-2 s-1 2 x 1032cm-2 s-1 2 x 1031 cm-2 s-1Search for SUSY Higgs, … 2001 2006 RUN0 1A 1B 2A 2B

  5. Tevatron Improvements total Run 1 data = 1 week running in Run 2b

  6. Tevatron Improvements • Fermilab’s current projections are: • L dt ~2 fb-1 by end of 2003 • L Dt ~15 fb-1 by end of 2007 • all at a cm energy of ~ 1.96 TeV • CDF/D0 pushing for a Run 2 target of 20-30 fb-1 • Compare this to Run 1 data with • L dt of ~ 0.10 fb-1 at cm energy = 1.80 TeV A. Goshaw PHENO 2001

  7. Potential Tevatron improvementsRun 2 vs Run 1 Process Production sensitivity p p -> X Y Mass Y GeV/c2 increase t t 175 1.4 x 200 W H 120 1.2 x 200 q q 300 1.8 x 200 g g 300 2.1 x 200 Sensitivity increase of Run 2 vs Run 1 200 - 400 A. Goshaw PHENO 2001

  8. CDF and D0 Detectors • The CDF and D0 detectors have been upgraded to handle the increased collision rate (132 ns crossing time) and an integrated luminosity up to ~ 5 fb-1 • In addition the detectors have been significantly rebuilt to qualitatively improve performance. • The transition from Run 2A to 2B will require a shutdown of ~ 6 months primarily to replace the silicon strip trackers. A. Goshaw PHENO 2001

  9. Calorimeters Tracker Muon System antiprotons protons Beamline Shielding 20 m Electronics

  10. [cm] First p p collisions of Run 2 at DØ Proton halo • Luminosity counters • timing Luminosity ( coincidence) ~5  1027 cm-2 sec-1 Antiproton halo • Vertex distribution along z of min bias events:

  11. Firstpp collisions of Run 2 at DØ • Calorimeter and forward muon hits in a minimum bias event

  12. y x • Silicon Tracker sections read out in first collisions H1 B1 B4 B6 H4 North F1 South F12 B6 F11 F11 B4 H4 3 H4-Wedge 4 y (cm) 4 F11-Wedge 12 F11-Wedge 3 12 Looking North x (cm) z (cm) South Hits found in data

  13. Offline track fitting 4 hit track found!! ? r (cm) y (cm) ? A second track? Maybe our first vertex? x (cm) z (cm) - Multiple scattering, alignment, etc not taken into account… - Many things to be understood/ bugs to be found yet but the start of silicon tracking at D0!

  14. 2 1/pT Tracks in the Fiber Tracker • Offline track finding frompp events: 5 points on a track Since B=0 for this run, real tracks should be found with 1/pT = 0

  15. x x x x x x x x x Silicon: Tracking Results • Offline tracking • 4 hit tracking • No alignment, multiple scattering, etc. included • Results match those from L3 • From the official, standard versions of offline reconstruction and L3 code 3D Event Displays

  16. First global tracking results: CFT + SMT Axial view Only part of the CFT & SMT are instrumented For this tracking results we require: 9 axial hits ( 5 CFT & 4 SMT) 4 corresponding stereo hits This is a tracking result from the first 36x36 store on Friday April 27, 2001 Side view

  17. RETAINED FROM CDF RUN I Solenoidal magnet Central and wall calorimeters Central and extension muon detectors NEW FOR CDF RUN II Tracking system Silicon vertex detector (SVXII) Intermediate silicon layers (ISL) Central outer tracker (COT) Scintillating tile end plug calorimeter Intermediate muon detectors Scintillator time of flight system Front-end electronics (132 ns) Trigger system (pipelined) DAQ system (L1, L2, L3) The CDF Detector

  18. m END WALL 2.0 HADRON = 1.0 n CAL. 0 30 SOLENOID 1.5 1.0 = 2.0 n END PLUG HADRON CALORIMETER COT END PLUG EM CALORIMETER .5 = 3.0 n 0 3 0 2.5 0 .5 1.0 1.5 2.0 3.0 m Intermediate silicon Inner silicon 1 or 2 layers 6 layers The CDF detector is basically new wire drift chamber (96 hits)TOF System • A new powerful 3d tracking system and vertex detector covering |h|out to 2.0. • A new scintillating tile plug calorimeter covering |h| out to 3.6.

  19. Performance of central outer tracker Commissioning with Reconstructed tracks from Cosmic ray tracks April 2000 p p collisions Low noise ! Run 2 Collisions !

  20. Silicon Tracking • The silicon strip detector is a stand-alone 3d tracking system • Impact parameter resolution sd =  a2 +(b/Pt)2 (a =7mm, b =20-30mm) • Increase in B tagging for t t : Run I Run II single tag 25% 52% double tag 8% 28%

  21. CDF Deadtimeless Trg&DAQ Calorimeter energy Central Tracker (Pt,f) Muon stubs Cal Energy-track match E/P, EM shower max Silicon secondary vertex Multi object triggers Farm of PC’s running fast versions of Offline Code  more sophisticated selections A. Goshaw PHENO 2001

  22. CDF Secondary Vertex Trigger NEW for Run 2 -- level 2 impact parameter trigger Provides access to hadronic B decays Data from commissioning run COT defines track SVX measures (no alignment or calibrations) at level 1 impact parameter s ~ 87 mm d (cm)

  23. CDF Particle ID • Scintillator bar TOF system with ~ 100ps resolution plus dE/dx from 96 hits in COT • Improves beauty flavor tagging and CP violation studies • For example measurement of mixing in Bso --> J/y f CDFI CDFII CDFII+TOF e D2 ~ 3% ~5% ~10% (e efficiency for tag, D dilution)

  24. Silicon Integration and Installation L00 Into SVXII SVXII into ISL Final Assembly Installation

  25. Some simple measurements Commissioning run data Ksp+p- L  p-p Level-3 tracking • Oppositely charged track pairs with large impact parameter and small z separation. Photon conversion in material radius r – f

  26. Opportunities in Run 2 • With these Tevatron, CDF and D0 detector upgrades, what is the physics potential of Run 2? • The details depend on specific physics channels, but it is easy to understand the big picture. Physics Potential for Run 2 = [Run I Physics Results] x A x D x E x I where A = Accelerator improvements ~ 200 - 400 (assume 20 fb-1) D = Detector upgrades ~ 2 – 3 (tt, Higgs, B physics) E = Experience working with the data > 1 (e.g. attained ~ 2 in I = new Ideas > 1 Run 1 top studies) A. Goshaw PHENO 2001

  27. QCD Physics QCD jets, photons, PDF’s, as Compositeness Diffraction Electroweak physics W boson properties Triboson coupling Drell-Yan, W’, Z’ searches Top physics Top quark properties Single and pair top production B physics B lifetimes, rare decays B mixing CP violation, CKM parameters Bc spectroscopy Theory-driven searches Higgs bosons SUSY particles Technicolor, leptoquarks, LED The experimenter’s delight - unexpected features of Nature The Physics Menu A. Goshaw PHENO 2001

  28. Cross sections for particle production vary by a factor of ~ 1010 (diffraction to Higgs) Enormous b rates > 104/s challenge: triggers, flavor tagging Large W boson samples challenge: lepton, MET precision Modest t t samples challenge: B’s in jets, jet Et Searches for Higgs, SUSY… challenge: backgrounds, statistics The Particle Menu SUSY LED ??

  29. Selected Run 2 Physics Topics • Precision W boson studies • Top quark physics program • The Tevatron as a B hadron factory • Comments on an adiabatic approach to the Higgs search • Next two talks: - SUSY, LED, … searches at the Tevatron in Run 2 - Higgs physics at hadron colliders A. Goshaw PHENO 2001

  30. Precision W boson Measurements • The baton is being passed from LEP to the Tevatron for precision vector boson studies. • For the Z boson LEP reigns supreme • MZ = 91.1882 + 0.0022 GeV/c2GZ = 2.4952 + 0.0026 GeV • decay modes, electroweak and QCD tests, new physics searches • Compared to current W boson measurements at the Tevatron • MW = 80.452 + 0.062 GeV/c2 • GW = 2.04 + 0.14 GeV (CDF) = 2.22 + 0.17 GeV (D0) (from W high mass tail)

  31. Run 2 W boson Measurements • The CDF and D0 experiments will make the most accurate W boson measurements until the LHC (?) or the (?) LC . • Run 2 prospects with combining 2 ( >10) fb-1 from CDF and D0 - dMW = 30 (20) MeV/c2 ( W mass errors ~ 10 dMZ ) - if there were no error on Mtop , aEM … ~30% error on Higgs mass - dGW ~ 40 MeV (from direct measurement) • Search for rare decays suppressed in SM • W -> p + g , DS + g • Based upon 2.3 x 108 W bosons (10 fb-1 of data) • Search for new W’ and Z’ bosons CDF Run 1 • Mz’ > 690 GeV/c2 Mw’ > 786 GeV/c2 • Run 2 projections: MV > ~ 1 TeV (for SM couplings)

  32. Silicon trackers work at hadron colliders (CDF Run 1) B detection efficiency will be improved in Run 2 with level 2 displaced vertex triggers (CDF and D0) CDF and D0 will have an excellent integrated program of top quark, B hadron studies. Top and Beauty physics(Experience from Run 1 Counts)

  33. W Decay Mode ln ln W jj jj q (1) DileptonSmall backgrounds, but very small cross section (2) Lepton + JetsGood cross section and manageable background (3) All JetsHuge QCD backgrounds b b b b b t ln ln W jj jj g q t b b b b b (1 (2 (3 Top Physics in Run 1 • Before Run 1 top quarks were a search, they ended up as a study. • Even though mass was unexpectedly HIGH • measurements were GOOD • Techniques were developed • using DATA to improve • S/B, mass measurement, • decay and production • properties

  34. Developing Measurement Techniques In Run 1 • D0 measurement of top mass from 6 dilepton events Mt = 168.4 + 12.8 GeV/c2 • CDF measurement using 76 lepton + jet events • Mt = 176.1 + 7.4 GeV/c2 A. Goshaw PHENO 2001

  35. Top mass in Run 1 -> 2 • Combine 3 CDF and 2 D0 top decay channels • Measurement comparable to precision • of b quark mass, and significantly • better than Run 1 projections. • Mt = 174.3 + 5.1 GeV/c2 • Mt / Mb = 36 + 2 Mt ~ scale of EWSB = (2 2 GF)-1/2 = 175 GeV/c2 • In Run 2 projections are dMt ~ 3 (~ 2) GeV/c2 with 2 (> 10) fb-1 for (CDF or D0)

  36. Top properties Mass ~ 175 GeV/c2 G ~ 1.5 GeV t ~ 4 x 10-25 (LQCD)-1 ~ 10-23 => free top decay Spin = ½ couplings = +2/3e , color triplet, weak (T3)L Mt – Mt bar = 0 (CPT test) Decay dominated by Wb mode - W helicity in top decay t -> W s BR ~ 10-3 t -> W d BR ~ 5 x 10-5 t -> g c,u BR ~ 10-8 T -> Z c,u BR ~ 10-12 Top Physics Program in Run 2(~ 2x105 top quarks with 15 fb-1 of data)

  37. Virtual Higgs via Mt and MW • Indirect EW fits to SM Higgs imply Tevatron has good hunting • Complementary to direct searches, sensitive to other new physics • RUN 1 Data Run 2 Projections

  38. Top production Top pairs: s (t t) ~ 7.0 pb QCD tests Anomalous couplings, new particles Differential production properties t-tbar spin correlations Top Pt Top Drell- Yan via ds/dM of t-tbar New Physics in X -> t t Single top: s (t b) ~ 1.6 pb - QCD tests |Vtb|, top form factor Top Physics Program in Run 2(~ 2x105 t t plus t b produced in 15 fb-1)

  39. Top Pair Production CDF and D0 Run 1 6.5 + 1.7 pb 5.5 + 1.7 pb Top pair cross section error (%) Potential sensitivity in 2 fb-1 for X -> t t with Mtt up to ~ 1 TeV Single top cross section error (%) Some Top Production Studies

  40. Summary of Projected Top Quark Measurements A. Goshaw PHENO 2001

  41. The Tevatron is a Full Service B Factory • B production rate is high: ~ 20 KHz @ L = 2 x 1032 cm-2s-1 • Data collection limited by offline bandwidth of ~50Hz • All B species are produced • B mixing measurements: • Bd , Bs access to |Vtd|/|Vts| • CP violation: • Bo -> J/y Ks , Bs -> J/yf , … • Rare decays • B hadron spectroscpy • QCD production studies • … 41 ps

  42. Mixing, CP violation search Inclusive B production properties |y| < 1.0 D0 CDF Data/NLO QCD ~ 2.5 Some results from Run 1 … World Sin2b CDF Bd mixing

  43. The CDF and D0 detectors are well tuned for B physics in Run 2 The Tool Kit • Better decay vertex measurements with 3d silicon trackers • Better tracking of decay particles • Better particle ID • Ability to trigger on all hadronic decays at level 2 • Improved flavor tagging

  44. Mixing in Bs decay Use Bs -> Dsp and Ds 3p - ~ 75,000 events (50% uncertainty) SM expectation: xs = Dms/Gs ~ 30 - DGs/Gs ~ 0.15 CP violation sin(2b) from Bo -> J/y Ks - 20,000 events (J/y -> m m) - s( sin(2b)) ~ 0.05 additional 10,000 J/y -> ee g from Bo -> p+ p- / Bs -> K+ K- ~ 5,000/~10,000 events s ( g ) ~ 7 o Assuming S/B ½; Xs = 40 ps-1 Aim for first sin(2b) measurement by summer 2002 44 Some examples (2 fb-1) of data

  45. The Higgs search will evolve out of studies of SM processes For example p p -> X + Y where X, Y are color singlets: p p -> W g , Z g p p -> W W, W Z, Z Z Use these to: Understand IS, FS radiation Tune di-jet resolution with Z -> bb, W -> c s Refine cuts s(p p -> W Z) x BR (Z -> bb) ~ 4 x s(p p -> W H) BR (H -> bb) for MH = 120 GeV/c2 must discover the Z before the H An adiabatic approach to the Higgs search … Search techniques developed Using Run 1 data

  46. An adiabatic approach to the Higgs search … D0 simulation of Z -> b b for 2 fb-1 Find a signal CDF Z -> b b data 120 GeV Higgs for 30 fb-1 Develop new jet measurements to improve the di-jet mass resolution D0 Higgs simulation CDF jet studies

  47. Summary • A LONG upgrade of the Fermilab accelerator complex and the CDF and D0 detectors is coming to an end. • This month the CDF and D0 detectors will continue commissioning with 36x36 p p collisions at 1.96 TeV • By Fall 2001 the experiments should be taking useful physics quality data. • An aggressive goal is first analysis results by summer 2002 • The CDF and D0 detectors upgrades are extensive • Maintain the strengths of the Run 1 detectors • Use Run 1 experience to make significant improvements • Select new categories of events using improved triggers • Each individual event will be measured with increased precision • The sensitivity of the Fermilab Run 2 physics program is ~ 500 x that of Run 1 for complex events with B hadrons ( ~20 fb-1). A. Goshaw PHENO 2001

  48. Summary (con.) • First 500 pb-1 by end of 2002 • Establish physics program, understand detector performance • B physics: CP violation, CKM matrix elements • First stage of new physics searches (follow up Run 1 anomalies) • Increase integrated luminosity to > 2 fb-1 by early 2004 • Precision studies of top and W physics • New tests of the SM and interesting indirect MHiggs constraints • Precision B physics program • Searches for SUSY and other new physics, hint of Higgs? • Proceed to highest attainable luminosity ~ 20 fb-1 by 2007 • Follow up previous discoveries or hints • Discover or exclude low mass Higgs • Provide material for an exciting PHENO2007 conference A. Goshaw PHENO 2001

  49. Summary (con.) • Let’s hope run 2 does not look like this! A. Goshaw PHENO 2001

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