Experimental program at accelerators

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Experimental program at accelerators
Run II
161.3 172
LEP I
LEP
135
183
189
196-200
pb- 1
175
5
1010
55
175
SLC/SLD
Tevatron
Run II (2TeV)
Run I (1.8TeV)
pb- 1
110
2-gt4 -gt 10-gt?
fb- 1
HERA
ep
e-p
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pb- 1
CESR
LHC (14TeV)
BaBar, Belle, HERA-B(?)

• Not shown ( bias ?)
• neutrino beam lines
• kaon beam lines

Worldwide HEP exp. program becoming thin...
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Run II status
Run II starting date is fixed !!

• Very serious deliberate effort to stay on
  schedule
• All parties involved Accelerator, CDF DØ
• Fallback/descoping plans in place
• Guarantee start on Run II on March 1, 2001
• Different approach to schedule at Fermilab

CDF DØ experiments

• Both upgraded and better detectors

• Decrease time between crossings (initially
  396nsec ? 132 nsec)
• Higher instantaneous lum. , new tracking systems

• Better trackers ( DØ solenoid)
• Silicon detectors ( b- tagging triggering)
• Better muon coverage
• Improved missing Et resolution (CDF forward
  calorimeters)

• Improved physics capabilities

• Detectors now very similar still different
  emphasis

• CDF tracking emphasis
• DØ calorimetry, muon ID

• Additional capabilities.

• CDF time of flight, extra silicon layers
• DØ forward proton detector

• Radiation hardness

• No problem up to 2-4 fb-1 (Run IIA)
• Beyond that (Run IIB), need to replaceparts of
  inner tracking systems time scale being
  discussed

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Lum. Projections for Run II
Possible Accumulation of Luminosity in the
pre-LHC Era
(S.Holmes, ICFA 99)
Run
2001 Main Injector and Recycler 0.6 fb-1 2002 Init
iate antiproton recycling 1.2 fb-1 2003 6 month
shutdown to install 0.8 fb-1 e-cool, 132 nsec,
etc 2004 Achieve 2x1032 cm-2sec-1 2.0 fb-1 2005
Achieve 3.5x1032 cm-2sec-1 3.5 fb-1 2006 Achieve
5x1032 cm-2sec-1 2.3 fb-1 6 month shutdown to
install C-0. 2007 Achieve 5x1032
cm-2sec-1 3.8 fb-1   TOTAL 15 fb-1
IIA
IIB
per experiment
Peak Lum is in units of 1032
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Run II physics results
Per experiment
Crucial
Run IIA
Run IIB
And always combine both experiments in working
groups
Personal note
Most exiting possibilities in area of L dt
20-40 x Run I
If hint of new physics ? continue If no new
physics increase in lum by factors 2 to 3 not
guaranteed worthwhile wait for LHC ?
HEP is a world wide program and we have a plan.
New physics will not be obvious precision
measurements require calibration understanding
not exploring totally new energy regime.
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SM-EW precision
Present SM Higgs Mass limits (95 CL) MH gt 107.7
GeV (direct) MH lt 188 GeV (indirect)
Plot emphasizes importance of top and W mass
measurements.
Bread butter physics of Run II
What is precision ?
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W mass in Run II
Error is already incredibly small
Future
Some more improvements from LEP II Improvements
at Tevatron for sure However not easy, given the
environment ( some indication already)
Scaling leads to error on order of
15-20 MeV/c2 per experiment in 2fb-1
( with correlations)
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Top mass future
(_at_1 TeV)
Run I result
174.33.2(stat)4.0(syst) GeV/c2
174.35.1 GeV/c2
Run II 2 fb-1
Event statistics (pair prod.) in 2fb-1
3 GeV/c2
Key ingredient is jet energy scale calibration.
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Conclusions

• The Tevatron is an immensely productive facility
• ?s from 3 GeV to 1 TeV
• Run II improves on Run I
• increased detector capabilities Higher rate
  capabilities, Heavy quark tagging, charged
  particle tracking, better trigger and DAQ and
  computing
• increased statistics (x20 or more) for standard
  model processes
• increased reach for new particle searches (Higgs,
  SUSY)
• Efforts now will lead to better physics later.

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W Width

• Run I Results shown below. Uncertainties scale
  not as well as ?N indirect, as ?N direct.

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Run I Wg, WW, WW/WZ Measurements

• Wg -gt eng, Wg-gtmng
• Search for WW-gtdileptons
• Search for A.C. in WW/WZ-gtenjj
• Search for A.C. in WW/WZ -gt mnjj and WZ-gt
  trileptons
• Run I Zg Measurements
• Search for A.C. in Zg -gt nng
• Zg -gt eeg, Zg-gtmmg

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Standard Model WWg WWZ Interactions
t-channel
u-channel
s-channel

• Self-interactions are a direct consequence of the
  non-Abelian SU(2)L x U(1)Y gauge symmetry.
• Trilinear Coupling Diagrams are involved in
  Vector Boson Pair Production.
• SM makes specific predictions for the strength of
  the couplings.

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Standard Model Interaction

• WW Production A Textbook Example
• t-channel matrix element (massless quarks and
  high-energy limit simplifies the calculation)
  gives
• and
  violating unitarity.
• Except, the s-channel matrix element has term of
  opposite sign. Unitarity isnt violated after
  all.

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WWZ/WWg Non-SM Interaction

• Characterized by effective Lagrangian
• CP Conserving SM Parameters
• lZ 0 lg 0
• Dk k-1 DkZ 0 Dkg 0
• g1Z 1
• Static W Properties

QeW - e (k-l) / M2W
mW e(1kl) / 2MW
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Effect of non-SM Couplings

• Cross section increases especially for High ET
  bosons (W/Z/g).
• Unitarity Violation avoided. e.g.

• L is a form factor scale

WW Production
s(WW)
PT(W)
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Predictions for WWg/WWZ Anomalous Couplings

• Diagrams like this for SM

• Table based on Ellison and Wudka
  hep-ph/9804322 (May 1998)

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D0 Combined and LEP
LEP Combined Moriond 00
D0 Combined
1s uncertainties L2 TeV
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Wg in Run II
Radiation Zero

• SM has amplitude zero at where
  is angle between incoming quark
  and photon in the Wg
  rest frame
  (W polarization -gt 73
  correct rest frame).
• Also manifested in Dh
• between photon and lepton
• Additional cuts mT(lnET)gt90 GeV/c2

1fb-1
Dhhg-hl
Anomalous Couplings

• If no new tricks
• But angle of lepton in Wg rest frame is
  additional info that can be used simultaneously
  w/ g ET spectrum.

(L2 TeV)
95 CL
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WW in Run II

• Measure Cross Section using lnln decays
• Lots of recent theory work on NLO calcs.
• background was Zs and Wg in Run I but signal
  to background should be better in Run II (through
  elimination of Wg) to g.t. 11.
• Ds/s 15
• Study W polarization using lnln decays.
• Measure A.C. limits as in Run I using both
  dilepton and semi-leptonic decay modes.
• e.g. WW(enjj)
• L 2 TeV (95 C.L.)

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WZ in Run II

• Observe measure the cross section using the 15
  detected llln (le and/or m).
• WZ-gtlnbb seems very interesting
• 50ish events after effys.
• Background is Wjets and amounts to (crude guess)
  a few hundred dual b-tags.
• Contributes to learning how to do Z-gtbbar.
• Anomalous Couplings
• trilepton mode limits may improve 6X assuming
  the obvious improvements in technique
• lnbb will be studied like WW-gtlnjj in Run I.

Run I Scaled Combined Wg/WW/WZ L2 TeV 95 CL
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ZZg/Zgg/ZgZ/ZZZ Interaction

• In SM all couplings equal to zero
• Zg final state
• Non-SM Characterized by an effective Lagrangian
  w/ 8 coupling parameters called h.
• CP Violating h1V and h2V
• CP Conserving h3V and h4V.
• ZZ final state
• Non-SM Characterized by an effective Lagrangian
  w/ 4 coupling parameters called f.
• P CP Violating f4V.
• P, C Violating CP Conserving f5V .
• Significant interference between f4g and f4Z
  as well as f5g and f5Z .

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Limits on Anomalous ZVg Couplings
Run I (ee,mm) Run1a(nn)
95 CL 2D Limits
hZ coupling limits identical

• LEP Combined Limits are Comparable

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Prospects for Run 2

• s of events _at_D0 (effy included).
  
• Zg _gt ee(mm)g 350
• Zg _gt bbg 1000
  
• ZZ_gt es and ms a few
• ZZ -gt ls and jets 200

• Zg in Run 2
• Charged lepton modes rely on e and m and g ID
  and is good development tool. What about the
  Run 1 bump?
• Neutrino mode relies on handling the backgrounds.
  Improved tracking, the new FPS and CPS will play
  a big role.
• New the bbar decay mode. jjg and jjj w/ (j-gtg)
  backgrounds will probably constrain this to limit
  setting.

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Prospects for Run 2

• Scaling rule for anomalous coupling limits Zg
  Limits could improve by the sqrt of the ratio of
  luminosities because of strong form factor
  dependance.
• Zg (Combined) at 95

TeV 2000 Report (1fb-1)
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ZZ in Run II

• Recent theory progress (Uli Baur Dave
  Rainwater)
• s(ZZ) 1 pb.
• Developed A.C. Monte Carlo.
• Studied prospects for Run II.

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ZZ Candidate from CDF

• Three Central Muons. One muon inferred from a
  high-PT track.
• Expected 0.1 event.

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ZZ in Run II

• ZZ-gt 4 charged leptons (es and/or ms)
• Backgroundless?
• Cross section and 1st A.C. limits
• ZZ-gt llnn
• backgrounds ttbar, WW, Z missing jet gt
  require pT(Z)gt40 GeV/c
• ZZ-gtlljj
• background is Zjets and is 10X.
• Limits this to A.C. analysis
• A.C. limits
• sensitivity of llnn and lljj similar
• This is 8X better than present LEP limits

LFF750 GeV 95 CL F4,5V lt 0.2
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Trilinear VVV Summary

• Tevatron will study Wg,WW,WZ, Zg, ZZ final states
  with a rich variety of techniques in Run II.
• Prospects for physics
• Wg radiation zero and A.C.s
• Zg events and A.C.s
• WW WZ cross sections, event properties and
  A.C.s
• Final states with bb
• First ZZ analyses.
• Theres a lot of room for improvement over Run 1
  and LEP.

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CDF B Lifetimes Run 1
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CP Violation in B Decays
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Measurement of sin2b

• Total reconstruction of B0 ? J/y KS ? mm-
  (ee-) pp-
• Measure proper decay time
• Tag the flavor of the B at production

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B0 ? J/y KS (CDF)

• more events in Run II by factors of
• 2000/110 for more luminosity
• 1.5 for longer SVX
• 2 for extended muon acceptance
• 10,000 events in Run II

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Methods of Flavour Tagging

• Opposites side tags - identify flavor of the
  other B in the event
• soft lepton b l - X
• jet-charge tags Qjet lt 0 for b
• Same side tags - correlation of flavour and
  charge of particles produced in fragmentation
• Efficiency (e ) and dilution factor (D)
• D 2 P - 1, P correct tag probability
• e D 2 is the tags effectiveness

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Flavour Tagging

• calibrate tags in Run II with
• 40 K B J/y K events
• 20 K B0 J/y K 0 events
• statistical error will be bigger than systematic

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CDF sin2b Expectations

• For a time integrated analysis,
• But, learning from Run I, we can do better with
  time dependent analysis.
• Most of the backgrounds are at small ts.
• Statistical error s (ACP) / D
• s (sin 2b ) 0.08 (0.07)
• with 10K events

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DØ sin2b Expectations

• invariant mass MB 15 MeV/c2
• (S/B 0.75)
• e D2 6.7 (CDF extrapolation)
• decreased error with time dependent analysis
  s(sin2b ) 0.07

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2002 - exciting times

• BaBar and BELLE will have results from their
  first physics runs (close to design luminosity)
• 1 - 30 fb-1 ? d(sin2b) 0.12 - 0.18
• DØ and CDF should have between 0.5 and 1.0 fb-1
  analyzed
• 3800 - 7500 fully reconstructed events
• d(sin2b) 0.10 - 0.15
• Combined Tevatron could beat em
• Everyone combined could signal new physics.

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B0 ? p p - (CDF)

• Huge background 1011 pb
• Displaced track trigger
• 2 opposite sign tracks
• pT gt 2(3) GeV/c
• Df cut to remove back-to-back tracks
• d0 gt 100 mm
• Background still high, but acceptable 102 pb
• Expect 5-20 K events in 2fb-1
• depending on branching ratios
  and accelerator configuration

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CDF sin2a Expectations

• Problems with Penguins
• ToF and theorist will help
• s(sin2a ) 0.09 assuming
• S 10K , S/B 1/4, e D2 9.1
• no Penguins

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BS Mixing (CDF)

• Use fully reconstructed events
• BS ? DS p 7 - 10 K
• BS ? DS p p -p 8 - 13 K
• e D2 5.7 , 11.3 with ToF
• s(t) 60 fs, 45 fs with L00 silicon

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CDF Expected xS Reach

• 5 s sensitivity up to xS 60

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B Physics Conclusions

• The upgraded Tevatron and our new detectors put
  us in a great position to make significant B
  physics measurements in Run II.
• sin2b to 0.07
• asymmetry associated with sin2a to 0.09
• Bs mixing up to xs 60
• maybe even sing
• This is just in the first two years - 2 fb-1. We
  wont stop there...

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New director - New Run II plan

• No long shutdowns
• Gradual luminosity improvements
• Run until LHC results tell us to stop
• 5 fb-1 per year at peak