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Production and Acceptance:
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Leading LO Feynman diagrams for stop pair
production. Same diagrams are applicable to the case of leptoquarks pair
production. Plot is available in EPS
or GIF format.
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Full event selection efficiency of this analysis
for region A (events passing all cuts and also  cuts) for
stop pair production followed by stop pair’s decay to one leptonic and one
hadronic tau and two b-jets. Plot is available in EPS or GIF
format.
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Control and Signal Regions:
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Number of jets distribution for events passing all
selection cuts and also MT<35 GeV/c2 cut. Electron
and muon channels are combined. Plot is available in EPS or GIF
format.
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Number of jets
distribution for events passing all selection cuts and also MT<35
GeV/c2 cut. Electron channel only. Plot is available in EPS or GIF format.
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Number of jets distribution for events passing all
selection cuts and also MT<35 GeV/c2 cut. Muon
channel only. Plot is available in EPS or GIF format.
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Tau candidate number of track distribution for
events passing all selection cuts and also njet<2 and MT<35
GeV/c2 cuts with one exclusion: the YT>85 GeV/c
cut is replaced with a cut  GeV/c. Plot is
available in EPS or GIF format.
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YT distribution
for events passing all selection cuts and also njet=0 and MT<35
GeV/c2 cuts. Plot is available in EPS
or GIF format.
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Exclusion Plots:
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Exclusion limit in the plane of the cross section
of stop pair production vs. stop mass:
Observed limit is shown as a red line; expected
limit is shown as a band and corresponds to 68% probability; theoretical
cross-section (solid line) and its uncertainty (dashed line); earlier limit
from CDF and LEP search for 3rd generation leptoquarks; CDF
Run-I limit for stop. Plot is available in EPS
or GIF
format.
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Exclusion limit in the plane of the cross section
of stop pair production vs. stop mass:
Same as above, but expected limit is not shown. Plot
is available in EPS
or GIF
format.
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Exclusion limit in the plane of the cross section
of stop pair production vs. stop mass:
Same as above, but no CDF Run-I limit for stop
shown. Plot is available in EPS
or GIF
format.
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Exclusion limit in the plane of the cross section
of 3rd generation leptoquark pair production vs. stop mass:
Observed limit is shown as a red line; theoretical
cross-section (solid line) and its uncertainty (dashed line); earlier limit
from CDF and LEP; limit obtained from CDF Run-I stop quark search. Plot is
available in EPS
or GIF
format.
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Kinematical Distributions for
Final Events:
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Distribution of the transverse energy, ET,
of the first leading jet in events passing all selection cuts and also  cuts
(primary signal region). Plot is available in EPS
or GIF format.
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Distribution of the transverse energy, ET,
of the second leading jet in events passing all selection cuts and also  cuts
(primary signal region). Plot is available in EPS
or GIF format.
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Distribution of the transverse momentum of the
leptonic tau candidate in events passing all selection cuts and also  cuts
(primary signal region). Plot is available in EPS
or GIF format.
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Distribution of the transverse momentum of the hadronic
tau candidate in events passing all selection cuts and also  cuts
(primary signal region). Plot is available in EPS
or GIF format.
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Distribution of the missing transverse energy in
events passing all selection cuts and also  cuts
(primary signal region). Plot is available in EPS
or GIF format.
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Distribution of MT(l,MET), the transverse mass of the
leptonic tau visible momentum and transverse missing energy, in events
passing all selection cuts and also  cuts
(primary signal region). Plot is available in EPS
or GIF format.
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Distribution of YT, the scalar sum of
transverse missing energy and visible transverse momenta of the two tau
candidates, in events passing all selection cuts and also  cuts
(primary signal region). Plot is available in EPS
or GIF format.
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Distribution of the invariant mass of the visible momenta
of the two tau candidates in events passing all selection cuts and also  cuts
(primary signal region). Plot is available in EPS
or GIF format.
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. This analysis uses about 200 pb-1 of data
collected by lepton+track triggers and investigates channels with one of the
taus decaying into leptonically and another one hadronically. In the primary
signal region, we expect 4.8±0.7 events and we observe 5 events. With
no excess, we set the upper limit on the cross-section production. . The lower
limit on the stop mass, assuming Br(stop-->tau b) = 100%, is 134 GeV/c2
for our nominal choice of the NLO cross-section for stop pair production. If
theoretical uncertainties due to PDF's
and factorisation scale are taken into acount, the limit is 129 GeV/c2.
