The Tevatron Connection

1
The TevatronConnection
and comparisons with theory!
A Few CDF Run 2 Proton-AntiProton Cross Sections

• Top Pair Cross-Section

• Single Top Cross-Section

• J/Y Cross-Section

• b-Hadron Cross-Section

• b-Jet b-DiJet Cross-Sections

• Charm Meson Cross-Sections

• g b/c Cross-Sections

• g g Cross-Section

• Z-boson Cross-Section

We now have over 400 pb-1 of data!

• W-boson Cross-Section

• Wn Jets Cross-Sections

• W/Z g Cross-Sections

• W W Cross-Section

• Z W Z Z Cross-Sections

• Inclusive Jet Cross-Sections

2
Top Pair Cross Section CDF Run 2 Summary
200 pb-1

• Observed cross sections consistent with each
  other and with the standard model prediction
  (1.96 TeV, mt 175 GeV)

Bonciani et al., Nucl. Phys. B529, 424
(1998) Kidonakis and Vogt, Phys. Rev. D68, 114014
(2003)
3
Single Top Cross Section CDF Run 2 Search
0.88 pb
1.98 pb

• Search for W 2 jets and tag one b. Do
  likelihood fit to HT (st channed combined).

st lt 10.1 pb _at_ 95 CL
sts lt 17.8 pb _at_ 95 CL
4
The J/Y Cross Section CDF Run 2

• The J/y inclusive cross-section includes
  contribution from the direct production of J/y
  and from decays from excited charmonium, Y(2S)?,
  and from the decays of b-hadrons, B-gt J/y X.

J/y coming from b-hadrons will be displaced from
primary vertex!
39.7 pb-1
Down to PT 0!
5
b-hadron Cross Section CDF Run 2

• Run 2 b-hadron PT distribution compared with
  FONLL (CTEQ6M).

Cacciari, Frixone, Mangano, Nason, Ridolfi

• Excellent agreement between theory and
  experiment!

39.7 pb-1
Y lt 1.0
b-hadron PT
6
b-Jet Cross Sections CDF Run 2
Arbitrary normalization!

• b-quark tag based on displaced vertices.
  Secondary vertex mass discriminates flavor.

• Require one secondary vertex tagged b-jet within
  0.1 lt ylt 0.7 and plot the inclusive jet PT
  distribution (MidPoint, R 0.7).

7
b-DiJet Cross Section CDF Run 2
Normalized to one!
bJet-bbarJet invariant mass
bJet-bbarJet Df

• Require two secondary vertex tagged b-jets within
  hlt 1.2. One of these tagged jets has to have a
  corrected tranverse energy greater than 30 GeV,
  the other has to have a raw transverse energy
  greater than 10 GeV.

8
Prompt Charm Meson Cross Sections CDF Run 2

• Theory calculation from M. Cacciari and P. Nason
  Resummed perturbative QCD (FONLL), JHEP 0309,006
  (2003)

9
g b/c Cross Sections CDF Run 2

• b/c-quark tag based on displaced vertices.
  Secondary vertex mass discriminates flavor.

10
g b/c Cross Sections CDF Run 2
g b
g c

• PYTHIA Tune A correctly predicts the relative
  amount of u, d, s, c, b quarks within the photon
  events.

ET(g) gt 25 GeV
11
g g Cross Section CDF Run 2
g g Df
g g mass

• Di-Photon cross section with 207 pb-1 of Run 2
  data compared with next-to-leading order QCD
  predictions from DIPHOX and ResBos.

12
Z-boson Cross Section CDF Run 2

• Impressive agreement between experiment and NNLO
  theory (Stirling, van Neerven)!

13
W-boson Cross Sections CDF Run 2

• Impressive agreement between experiment and NNLO
  theory (Stirling, van Neerven)!

14
W n Jets Cross Sections CDF Run 2

• Run 2 W n Jets Cross Section compared with Run
  1 (JetClu, R 0.4).

• Run 2 data compared with Alpgen HERWIG.

15
W g Cross Sections CDF Run 2
ET(g) gt 7 GeV R(lg) gt 0.7
16
Z g Cross Sections CDF Run 2
Note ?(W?)/?(Z?) 4 while ?(W)/?(Z) 11
ET(g) gt 7 GeV R(lg) gt 0.7
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WW Cross Section CDF Run 2
Campbell Ellis 1999
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ZW, ZZ Cross Sections CDF Run 2
Upper Limit
19
Inclusive Jet Cross Section CDF Run 2
353 pb-1!
ET gt 500 GeV!
Parton Level!
Calorimeter Level!

• The challenge is that we measure the jets at the
  calorimeter level. We do not measure partons!

20
Inclusive Kt Jet Cross Section CDF Run 2
I wish we had a QCD NLO Monte-Carlo Model with
Parton-Showers, Fragmentation, Beam-Beam Remnants,
etc.!
We are using Kt and MidPoint in Run 2!

• The Run 2 Kt inclusive jet cross section compared
  with PYTHIA Tune A (CTEQ5L).