Search for dark matter pair production in events with a hadronically decaying $W$ or $Z$ boson and missing transverse momentum in $pp$ collision data at $\sqrt{s}=8$ TeV with the ATLAS detector
A search is presented for dark matter pair production in association with a $W$ or $Z$ boson in $pp$ collisions corresponding to 20.3 fb$^{-1}$ of integrated luminosity at $\sqrt{s}=8$ TeV using data recorded with the ATLAS detector at the Large Hadron Collider. Events with large missing transverse momentum and a jet with mass consistent with a $W$ or $Z$ boson decay are analyzed. The data are consistent with the Standard Model expectations, and limits are set on the mass scale in effective field theories which describe the interaction of dark matter and Standard Model particles.
15 July 2013
These preliminary results are superseded by the following paper:
EXOT-2012-27
ATLAS recommends to use the results from the paper.
Figures
Figure 01a
Pair production of WIMPs (χχ) in proton-proton collisions at the LHC via an unknown intermediate state, with initial-state radiation of a W boson.
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Figure 01b
Pair production of WIMPs (χχ) in proton-proton collisions at the LHC via an unknown intermediate state, with initial-state radiation of a W boson.
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Figure 02a
Data and predicted background in the control region with one muon, one large-radius jet, two additional narrow jets and at least one b-tag and ETmiss > 250 GeV. Uncertainties include statistical and systematic sources.
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Figure 02b
Data and predicted background in the control region with one muon and ETmiss > 350 GeV (bottom). Uncertainties include statistical and systematic sources.
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Figure 03a
Data and predicted background in the signal region ETmiss > 350 GeV. Combined single W/Z boson signal distributions of D5 destructive and D5 constructive case with dark matter mass of 1 GeV and M* = 1 TeV are drawn as well. Uncertainties include statistical and systematic contributions.
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Figure 03b
Data and predicted background in the signal region ETmiss > 500 GeV. Combined single W/Z boson signal distributions of D5 destructive and D5 constructive case with dark matter mass of 1 GeV and M* = 1 TeV are drawn as well. Uncertainties include statistical and systematic contributions.
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Figure 04
Summary of observed limits on the effective theory mass scale M* at 90% CL for various operators from combined single W/Z boson signals. M* values below these lines are excluded.
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Figure 05a
Limits on χ-nucleon cross sections, compared to previous limits set by direct dark matter detection experiments and by the ATLAS 7 TeV monojet analysis. The plot shows the limits for spin-independent scattering. All limits are shown at 90% CL.
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Figure 05b
Limits on χ-nucleon cross sections, compared to previous limits set by direct dark matter detection experiments and by the ATLAS 7 TeV monojet analysis. The plot shows them for spin-dependent scattering. All limits are shown at 90% CL.
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Figure 06
Fraction of W bosons in combined single W/Z-boson signal samples at different dark matter masses.
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Figure 07a
Limits on σ × A × ε as a function of W-boson fraction in combined single W/Z-boson signal samples, derived from taking W- and Z-boson peaks in D5 destructive operator mχ = 1 GeV. Limits from signal region (SR) ETmiss > 350 GeV.
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Figure 07b
Limits on σ × A × ε as a function of W-boson fraction in combined single W/Z-boson signal samples, derived from taking W- and Z-boson peaks in D5 destructive operator mχ = 1 GeV. Limits from SR ETmiss > 500 GeV.
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Figure 08a
90% CL M* limits for D9 operator from combined mono-W-boson and mono-Z-boson signals from SR ETmiss > 500 GeV.
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Figure 08b
90% CL M* limits for D5 constructive operator from combined mono-W-boson and mono-Z-boson signals from SR ETmiss > 500 GeV.
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Figure 09
90% CL M* limits for D5 destructive operators from combined mono-W-boson and mono-Z-boson signals from SR ETmiss >350 GeV.
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Figure 10a
90% CL M* limits for D1 operator from combined mono-W-boson and mono-Z-boson signals from SR ETmiss >500 GeV.
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Figure 10b
90% CL M* limits for C1 operator from combined mono-W-boson and mono-Z-boson signals from SR ETmiss > 500 GeV.
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Figure 11a
Reconstructed jet mass in Z(μμ) control region with ETmiss > 350 GeV.
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Figure 11b
Reconstructed jet mass in low-ETmiss control region with ETmissin [ 250, 350 ] GeV.
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