Latest Results from Run 2 at D

1
Latest Results from Run 2 at DØ

• Last updated Nov. 13, 2001
• Boaz Klima
• (klima_at_fnal.gov)

2
Z ? ee- Candidates
2 EM objects, ET gt 20 GeV, isolation and shower
shape cuts
DØ
mZ
e
e
(uncalibrated energy scale)
Leo Chan, Rochester
3
W? e? Candidates
ET
e
EM cluster with track
mT(e,n) L0.1pb-1
EM cluster with track
Vishnu Zutshi NIU
4
Higgs Candidate (just kidding)
DØ W 2 jet candidate
Jet 1 ETraw 17 GeV
ET
Electron
Electron
Jet 1
Jet 2
Jet 2 ETraw 13 GeV
Jet ET corrections will be relatively large
5
Z ? mm- Candidate

• Two muons recoiling against a jet
• Dimuon invariant mass 55 GeV (with large
  uncertainty)

Onne Peters NIKHEF
6
J/? ???-
Di-muons reconstructed in the forward region
Roger Moore and Adam Yurkewicz, MSU
7
Muons in Jets
Onne Peters, NIKHEF
Back to back calorimeter jets
Muon in jet (b candidate) Hits in A,B,C layers
8
Jet pT Distribution
Using R0.7 Cone Algorithm with Run 1 corrections
Alexander Kupco Prague
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Jet Energy Calibration
?
jet
DØ
DØ
DØ
Ia Iashvili, Riverside
10
Ks ?pp-
Tracks reconstructed in the SMT detector
Brad Abbott, Oklahoma
Black histogram opposite-sign tracks Red
histogram same-sign tracks Dotted curve fit
to background Full curve fit to signal
background
DØ
11
Ks (?pp-) Lifetime
Tracks reconstructed in the SMT detector
Ariel Schwartzman, Buenos Aires
l ( )
12
Level 3 Calorimeter Trigger
EM clusters, pT gt 10 GeV Isolated, EM fraction gt
0.9 ? lt 1.1
Jets, pT gt 15 GeV R 0.7 cone ? lt 1.1
fail (prescaled)
fail (prescaled)
pass
pass
Volker Buescher, Mainz