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

A. Goshaw PHENO 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

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

4 Tevatron Improvements Discovery of top, B c, … 5x cm -2 s -1 2 x cm -2 s -1 2 x cm -2 s -1 Search for SUSY Higgs, … RUN 0 1A 1B 2A 2B

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

A. Goshaw PHENO 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 fb -1 Compare this to Run 1 data with  L dt of ~ 0.10 fb -1 at cm energy = 1.80 TeV Tevatron Improvements

A. Goshaw PHENO Potential Tevatron improvements Run 2 vs Run 1 Process Production sensitivity p p -> X Y Mass Y GeV/c 2 increase t t x 200 W H x 200 q q x 200 g g x 200 Sensitivity increase of Run 2 vs Run

A. Goshaw PHENO 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.

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

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

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

12 x y B6 B4 F11 North South H1 H4 F1 F11 F12 B1 B4B6 Looking North 12 3 Silicon Tracker sections read out in first collisions H4 4 H4-Wedge 4 F11-Wedge 3F11-Wedge 12 South Hits found in data x (cm) y (cm) z (cm)

13 - 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! ? ? A second track? Maybe our first vertex? z (cm) r (cm) y (cm) x (cm) 4 hit track found!! Offline track fitting

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

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 x x x x x x x x x

16 First global tracking results: CFT + SMT Axial view Side 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

17 The CDF Detector 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)

18 The CDF detector is basically new wire drift chamber (96 hits) TOF System A new powerful 3d tracking system and vertex detector covering |  |out to 2.0. A new scintillating tile plug calorimeter covering |  | 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  d =  a 2 +(b/P t ) 2 (a =7  m, b =20-30  m) Increase in B tagging for t t : Run I Run II single tag 25% 52% double tag 8% 28%

A. Goshaw PHENO CDF Deadtimeless Trg&DAQ Calorimeter energy Central Tracker (Pt,  ) 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

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  ~ 87  m 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 B s o --> J/  CDFI CDFII CDFII+TOF  D 2 ~ 3% ~5% ~10% (  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 Photon conversion in material radiusr –  K s          p Level-3 tracking âOppositely charged track pairs with large impact parameter and small z separation.

A. Goshaw PHENO 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 ~ (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 The Physics Menu QCD Physics –QCD jets, photons, PDF’s,  s –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 –B c spectroscopy Theory-driven searches –Higgs bosons –SUSY particles –Technicolor, leptoquarks, LED The experimenter’s delight - unexpected features of Nature

28 The Particle Menu Cross sections for particle production vary by a factor of ~ (diffraction to Higgs) Enormous b rates > 10 4 /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 SUSY LED ??

A. Goshaw PHENO 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

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 – M Z = GeV/c 2  Z = GeV –decay modes, electroweak and QCD tests, new physics searches Compared to current W boson measurements at the Tevatron –M W = GeV/c 2 –  W = GeV (CDF) = 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 -  M W = 30 (20) MeV/c 2 ( W mass errors ~ 10  M Z ) - if there were no error on M top,  EM … ~30% error on Higgs mass  W ~ 40 MeV (from direct measurement) Search for rare decays suppressed in SM –W -> , D S +  –Based upon 2.3 x 10 8 W bosons (10 fb -1 of data) Search for new W’ and Z’ bosons CDF Run 1 –Mz’ > 690 GeV/c 2 Mw’ > 786 GeV/c 2 –Run 2 projections: M V > ~ 1 TeV (for SM couplings)

Top and Beauty physics (Experience from Run 1 Counts) 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.

33 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 Top Physics in Run 1 W b W b q q l b l b jj b l b l b b b b W Decay Mode (1) Dilepton Small backgrounds, but very small cross section (2) Lepton + Jets Good cross section and manageable background (3) All Jets Huge QCD backgrounds g t t (3 (2 (1

A. Goshaw PHENO 2001 Developing Measurement Techniques In Run 1 CDF measurement using 76 lepton + jet events M t = GeV/c 2 D0 measurement of top mass from 6 dilepton events M t = GeV/c 2

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. M t = GeV/c 2 M t / M b = M t ~ scale of EWSB = (2  2 G F ) -1/2 = 175 GeV/c 2 I n Run 2 projections are  M t ~ 3 (~ 2) GeV/c 2 with 2 (> 10) fb -1 for (CDF or D0)

36 Top Physics Program in Run 2 (~ 2x10 5 top quarks with 15 fb -1 of data) Top properties Mass ~ 175 GeV/c 2  ~ 1.5 GeV  x – (  QCD ) -1 ~ => free top decay Spin = ½ couplings = +2/3e, color triplet, weak (T 3 ) L M t – M t bar = 0 (CPT test) Decay dominated by Wb mode - W helicity in top decay –t -> W sBR ~ –t -> W d BR ~ 5 x –t ->  c,uBR ~ –T -> Z c,uBR ~

37 Virtual Higgs via M t and M W 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 Physics Program in Run 2 (~ 2x10 5 t t plus t b produced in 15 fb -1 ) Top production  Top pairs:  t t) ~ 7.0 pb -QCD tests -Anomalous couplings, new particles Differential production properties –t-tbar spin correlations –Top P t –Top Drell- Yan via d  /dM of t-tbar –New Physics in X -> t t Single top:  t b) ~ 1.6 pb - QCD tests –|V tb |, top form factor

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

A. Goshaw PHENO Summary of Projected Top Quark Measurements

41 The Tevatron is a Full Service B Factory B production rate is high: ~ 20 L = 2 x cm -2 s -1 Data collection limited by offline bandwidth of ~50Hz All B species are produced B mixing measurements: –B d, B s access to |V td |/|V ts | CP violation: –B o -> J/  K s, B s -> J/  , … Rare decays B hadron spectroscpy QCD production studies … 41 ps

42 Some results from Run 1 … Mixing, CP violation search Inclusive B production properties |y| < 1.0 D0 CDF Data/NLO QCD ~ 2.5 World Sin2  CDF B d 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

Some examples (2 fb -1 ) of data Mixing in Bs decay Use B s -> D s  and D s 3  - ~ 75,000 events (50% uncertainty) SM expectation: –x s =  m s /  s ~ 30 -  s /  s ~ 0.15 CP violation sin(2  ) from B o -> J/  K s - 20,000 events (J/  ->  ) -  sin(2  )) ~ additional 10,000 J/  -> ee   from B o ->      B s -> K + K - -~ 5,000/~10,000 events  (  ) ~ 7 o -Assuming S/B ½; X s = 40 ps -1 Aim for first sin(2  ) measurement by summer

45 An adiabatic approach to the Higgs search … 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 , Z  –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  (p p -> W Z) x BR (Z -> bb) ~ 4 x  (p p -> W H) BR (H -> bb) for M H = 120 GeV/c 2 must discover the Z before the H Search techniques developed Using Run 1 data

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

A. Goshaw PHENO 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 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 M Higgs constraints –Precision B physics program –Searches for SUSY and other new physics, hint of Higgs? Proceed to highest attainable luminosity ~ 20 fb -1 by Follow up previous discoveries or hints -Discover or exclude low mass Higgs -Provide material for an exciting PHENO2007 conference

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