High Energy Physics @

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High Energy Physics _at_

• High energy physics at the 2 Tev Tevatron
  proton-antiproton collider

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CDF Group
CDF experimental group Tevatron 2 TeV ppbar
collider
Faculty Duncan Carlsmith, Matthew Herndon and
Lee Pondrom
Scientists James Bellinger, Woo-Hyun Chung
Research Assistants Varsha Ramakrishnan
and Jason Nett (graduated this year!)

• Wisconsin involved in BMU detector maintenance,
  detector operations, trigger, software
  operations, tracking and BMU software, silicon
  and BMU muon data validation, shifts, reviewing
  analysis, leadership, and physics!

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CDF Wisconsin Physics

• Direct searches for New Physics
• Z ? ?? Prof. Carlsmith (investigating ee
  signal, published)
• Jet Physics QCD and New Physics
• Quark substructure Prof. Pondrom
• Double parton interactions V.Ramakrishnan, Prof.
  Carlsmith adv.
• B Physics
• Discovery of B and ?b, Pursley (published)
• Bs ???- D. Sperka (U grad graduated) and
  Prof. Herndon (published)
• Higgs and diboson Physics
• H?WW analysis Herndon, Pursley, Nett(three
  publications, one publication in process)
• WW, Herndon and Pursley (published) and WZ,
  Herndon and Nett (publication in process)
• CDF Wisconsin group is pursuing an interesting
  and diverse physics program

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SM Higgs H?WW

• H?WW?l?l? - signature Two high pT leptons and
  MET
• Primary backgrounds SM diboson (WW, WZ, ZZ) and
  top in di-lepton decay channel
• Key issue Maximizing signal acceptance
• UW innovations. Adding channels channels
  sensitive to associated production
  and vector boson fusion 50
  acceptance! Also designed treatment of
  systematic uncertainties.

First Pheno paper Han
Spin correlation Charged leptons go in the same
direction
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CDF H?WW Search

• Inclusive search for high mass Higgs with H ? WW
• High mass analysis the most sensitive analysis
  for mH gt 128GeV

H?WW Channels Limits _at_ 165 GeV Exp. Limit
gg?H 0 Jets 1.67
gg?H 1 Jet VH, VBF 2.35
gg?H, VH, VBF 2 Jets 3.16
VH Trilepton 4.62
VH SS leptons 4.86
gg?H low mll 11.2
gg?H tl 14.5
Combined 1.00

• Have reached SM sensitivity at high mass!

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Tevatron Higgs Search
Exp. Exclusion 156-173 GeV 0.76xsSM _at_ 165 GeV
Obs. Exclusion 158-175 GeV
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Discovery

• Exclusion and Discovery projections chance of 3?
  discovery!
• Expect exclusion from CDF alone this year
• Sensitivity for order 135-185GeV exclusion from
  Tevatron in one year
• PAC recommended 3 year extension of Tevatron
  running
• Tevatron can discover the Higgs before the LHC!
• gt70 chance of 3? discovery with run 3.

This could be your Ph.D. thesis!
Low Mass discovery
High Mass exclusion
Good Data? Run 3
Analyzed?