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INVISIBLE HIGGS Kenji Hamano (University of Victoria) on behalf of the ATLAS and CMS Collaborations
04 April 2017 DM@LHC2017, UCI 1
Invisible decay of 125 GeV Higgs • Concentrate on the 125 GeV Higgs.
• BSM Higgs is covered by Tongguang Cheng. • 2HDM Higgs is covered in mono-H talk by Nicolo Trevisani.
• Physics motivation: • 125 GeV H as a part of SUSY: H -> neutralino. • Extra dimension: H -> graviscalars. • H -> dark matter (DM) particles.
• Indirect constraints from the 125 GeV Higgs measurements: • Non-SM decay BF < 0.34 at 95 % CL. (arXiv:1606.02266[hep-ex],
ATLAS+CMS, 5 (7 TeV) + 20 (8 TeV) fb-1) • SM predicts BF(H -> 4v) ~ 0.1 %. Any deviation from it is an
indication of new physics.
04 April 2017 DM@LHC2017, UCI 2
Higgs production and final states • 3 major Higgs production modes: • Associated production (ZH inv (leptonic))
(VH inv (hadronic)) • Tag on Z -> ll or V(Z or W) -> jet(s) • Same final state to mono-Z (lep) and mono-V
(had) searches
• Vector Boson Fusion (VBF H inv) • Tag on the 2 jets. • Same final state to mono-V(jj) searches.
• Gluon Gluon Fusion (ggH inv) • Tag on ISR jet. • Same final state to mono-jet search.
04 April 2017 DM@LHC2017, UCI 3
ZH inv. leptonic mode • Z decays to 2 leptons (electrons or muons).
04 April 2017 DM@LHC2017, UCI 4
ATLAS CMS Data set 13 TeV, 13.3 fb-1 13 TeV, 12.9 fb-1
Document ATLAS-CONF-2016-056 CMS PAS EXO-16-038
Object selection
Leading lepton pT > 30 GeV Sub leading lepton pT > 20 GeV |eta| < 2.5
Leading electron pT > 25 GeV Leading muon pT > 20 GeV Sub leading lepton pT > 20 GeV
Z selection |M(ll) – M(Z)| < 15 GeV -15 GeV < M(ll) – M(Z) < 10 GeV
Event selection 3rd lepton veto B-jet veto Missing ET > 90 GeV ΔR(ll) < 1.8 Δφ(pT(ll), MET) > 2.7 ||MET + jet pT| - pT(ll)|/pT(ll) < 0.2 Δφ(MET, jets) > 0.7 pT(ll)/mT < 0.9
3rd lepton veto 0 or 1 jet(s), Tau-jet veto Missing ET > 100 GeV pT(ll) > 60 GeV Δφ(pT(ll), MET) > 2.8 |MET - pT(ll)|/pT(ll) < 0.4 Δφ(MET, jet) > 0.5
ZH inv. leptonic: Background • Background estimation
04 April 2017 DM@LHC2017, UCI 5
Background ATLAS CMS
ZZ MC simulation MC simulation
WZ 3 lepton control region MC simulation
Z + jets ABCD method MET sideband
Non-resonant (WW, ttbar, …)
eµ control region eµ control region
ZH inv. leptonic: WZ Background • 3-lepton control region:
W(lv)Z(ll) dominated. • Normalization factor
data/MC is derived in this region • Contributions from other
processes are subtracted using MC.
• Normalization factor: 1.25 +/- 0.04 (stat) +/- 0.05 (sys)
• Apply it to signal region.
04 April 2017 DM@LHC2017, UCI 6
The normalization factor is applied in this plot
ZH inv. leptonic: Z+jets Background • ABCD method
• Use two least correlated variables • Frac pT = ||MET + jet pT| - pT(ll)|/pT(ll) • Δφ(pT(ll), MET)
• A = C*(B/D)
• MET sideband • Use MC. • Apply scale factor from MET
sideband.
04 April 2017 DM@LHC2017, UCI 7
Region Frac pT Δφ
A (signal region)
< 0.2 > 2.7
B > 0.2 > 2.7
C < 0.2 < 2.7
D > 0.2 < 2.7
ZH inv: non-resonant Background • eµ control region:
W(ev)W(µv’) and t(evq)tbar(µv’q’) dominated.
• Signal region (ee or µµ) is the half of eµ. • Other processes are
subtracted using MC. • Efficiency correction factor
between ee and µµ is applied (for the extrapolation to the signal region).
04 April 2017 DM@LHC2017, UCI 8
ZH inv. leptonic: Signal region • Signal region
• ATLAS: 456 events. • CMS: 265 events.
• Main systematic errors: • ZZ: MC correction (scale) factors
such as lepton energy and resolution, particle ID and trigger efficiency.
• ZZ: theoretical uncertainties. • Z+jets: correlation between ABCD
cuts.
04 April 2017 DM@LHC2017, UCI 9
9.2 Limit on invisible Higgs boson decays 9
Figure 1: Left: Distribution of the EmissT after the full selection except that 50 GeV < Emiss
T < 100GeV. Right: The Emiss
T in the signal region. The error bars represent statistical uncertainty, andthe shaded bands represent systematic uncertainty. The histogram stack correspond to the sumof all background predictions, the dots are the data, the red line is the prediction for the Z(``)H(mH = 125 GeV) signal, and the dashed green line is the prediction for the DM signal for thesimplified model with vector mediator with (mc, MV) = (150, 500) GeV. The DM signal yieldis multiplied by a factor three.
Figure 2: The 95% CL observed limits on signal strength sobs/sth in both vector (left) and axial-vector (right) coupling scenario, for coupling gq = 0.25. The expected exclusion curves forunity signal strength are shown as a reference.
ZH inv. leptonic: Limits • At 95 % CL • σ(Z(ll)H)*BF(H->inv) limit
• BF(H -> inv) limit
04 April 2017 DM@LHC2017, UCI 10
Observed Expected 0.98 0.65
Observed Expected 88 fb 58 fb
Observed Expected 0.86 0.70
ATLAS
CMS
ATLAS
9.2 Limit on invisible Higgs boson decays 9
Figure 1: Left: Distribution of the EmissT after the full selection except that 50 GeV < Emiss
T < 100GeV. Right: The Emiss
T in the signal region. The error bars represent statistical uncertainty, andthe shaded bands represent systematic uncertainty. The histogram stack correspond to the sumof all background predictions, the dots are the data, the red line is the prediction for the Z(``)H(mH = 125 GeV) signal, and the dashed green line is the prediction for the DM signal for thesimplified model with vector mediator with (mc, MV) = (150, 500) GeV. The DM signal yieldis multiplied by a factor three.
Figure 2: The 95% CL observed limits on signal strength sobs/sth in both vector (left) and axial-vector (right) coupling scenario, for coupling gq = 0.25. The expected exclusion curves forunity signal strength are shown as a reference.
Mono-Z Dark matter limits are also given
VH inv. hadronic mode • ATLAS, 8 TeV, 20.3 fb-1 (arXiv:1504.04324[hep-ex]). • W or Z -> 2 jets
• Accept 3 jets events to improve signal efficiency.
• Event selection: Backgrounds:
04 April 2017 DM@LHC2017, UCI 11
Item cut
Missing transverse momentum ET
MET > 120 GeV
Missing scalar sum of jet pT
HT > 120 GeV
Angular cuts Δφ(MET, pTmiss) < π/2
Min[Δφ(MET,jets)]>1.5
Background Method W+jets W+jets control region Z+jets Z+jets control region ttbar Ttbar control region Diboson, top MC Mulit-jet ABCD method
pTmiss = track based missing momentum
Control region -> scale factor -> apply to MC
More details covered in mono-V talk by Shuichi Kunori
VH inv. hadronic: Results • Signal Region:
• Systematic errors: • Jet and missing ET reconstruction. • Diboson: MC modeling uncertainties. • Z+jets, W+jets: jet flavor composition, pT
and m(jj) distributions (modelling).
04 April 2017 DM@LHC2017, UCI 12
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Figure 1: The missing transverse momentum (EmissT ) distributions of the 2-jet events in the signal region for the
(a) 0-b-tag, (b) 1-b-tag and (c) 2-b-tag categories. The data are compared with the background model after thelikelihood fit. The bottom plots show the ratio of the data to the total background. The signal expectation formH = 125 GeV and BR(H ! inv.) = 100% is shown on top of the background and additionally as an overlay line,scaled by the factor indicated in the legend. The total background before the fit is shown as a dashed line. Thehatched bands represent the total uncertainty on the background.
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Figure 2: The missing transverse momentum (EmissT ) distributions of the 3-jet events in the signal region for the
(a) 0-b-tag, (b) 1-b-tag and (c) 2-b-tag categories. The data are compared with the background model after thelikelihood fit. The bottom plots show the ratio of the data to the total background. The signal expectation formH = 125 GeV is shown on top of the background and additionally as an overlay line, scaled by the factor indicatedin the legend. The total background before the fit is shown as a dashed line. The hatched bands represent the totaluncertainty on the background.
11
Observed events 2-jets 3-jets 0 b-tag 47,404 18,442 1 b-tag 3,831 1,842 2 b-tag 344 159
VH inv. hadronic: Limits • M(H) = 125 GeV at 95 % CL. • σ(VH)*BF(H->inv) limits:
• BF(H->inv) limits:
04 April 2017 DM@LHC2017, UCI 13
[GeV]H m120 140 160 180 200 220 240 260 280 300
inv.
) [pb
]→
BR(
H×
VHσ
95%
CL
limit
on
-110
1
Observed (CLs)Expected (CLs)
σ 1±σ 2±
inv.)→jj) H(→W/Z(
ATLAS-1 = 8 TeV 20.3 fbs
Figure 6: Upper limits on �VH ⇥ BR(H ! inv.) at 95% CL for a Higgs boson with 115 < mH < 300 GeV. The fulland dashed lines show the observed and expected limits, respectively.
At mH = 125 GeV, for VH production, a limit of 1.1 pb is observed compared with 1.1 pb expected.These combined results for VH production assume the SM proportions of the WH and ZH contributions.Observed (expected) limits are also derived for the two contributions separately, 1.2 (1.3) pb for WH and0.72 (0.59) pb for ZH. As shown in Table 4, the 2-tag categories are almost only sensitive to ZH, the1-tag categories are equally sensitive to WH and ZH, and the 0-tag categories are more sensitive to WHproduction. The two processes contribute approximately equally to the sensitivity.
For the discovered Higgs boson at mH = 125 GeV, an observed (expected) upper limit of 78% (86%)at 95% CL on the branching ratio of the Higgs boson to invisible particles is set. These limits are de-rived assuming SM production and combining contributions from VH and gluon-fusion processes. Thegluon-fusion production process contributes about 39% (29%) to the observed (expected) combined sens-itivity.
8 Summary
In summary, Higgs boson decays to particles that are invisible to the ATLAS detector are searched forin the final states of two or three jets and large missing transverse momentum in a pp collision datasetcorresponding to an integrated luminosity of 20.3 fb�1 at a centre-of-mass energy of 8 TeV. No excessof events over the expected backgrounds is observed. The results are used to constrain the cross sectionfor VH production followed by the decay H ! inv. for 115 < mH < 300 GeV. The observed 95% CLupper limit on �VH ⇥BR(H ! inv.) varies from 1.6 pb at 115 GeV to 0.13 pb at 300 GeV. Assuming SMproduction and including the gg! H contribution, an observed (expected) upper limit of 78% (86%) onBR(H ! inv.) is derived for the discovered Higgs boson with mH = 125 GeV. This independent result iscomparable to that of the ATLAS ZH search with Z ! `` and H ! inv. [19].
15
Observed Expected 1.1 pb 1.1 pb
Observed Expected 0.78 0.86
VBF H inv. • ATLAS, 8 TeV, 20.3 fb-1 (arXiv:1508.07869[hep-ex]). • Event selection
• Background • W+jets: W+jets control region (Only one lepton) • Z+jes: Z+jets control region (|m(ll) – m(Z)| < 25 GeV) • Multi-jets: jet smearing method (à see the reference)
04 April 2017 DM@LHC2017, UCI 14
separation in pseudorapidity �⌘ j j as shown in Table 1. The SR1 selection requires events to have two
Table 1: Summary of the main kinematic requirements in the three signal regions.
Requirement SR1 SR2a SR2bLeading Jet pT >75 GeV >120 GeV >120 GeV
Leading Jet Charge Fraction N/A >10% >10%Second Jet pT >50 GeV >35 GeV >35 GeV
m j j >1 TeV 0.5 < m j j < 1 TeV > 1 TeV⌘ j1 ⇥ ⌘ j2 <0|�⌘ j j| >4.8 >3 3 < |�⌘ j j| < 4.8|�� j j| <2.5 N/A
Third Jet Veto pT Threshold 30 GeV|�� j,Emiss
T| >1.6 for j1, >1 otherwise >0.5
EmissT >150 GeV >200 GeV
jets: one with pT > 75 GeV and one with pT > 50 GeV. The ~EmissT is constructed as the negative vectorial
sum of the transverse momenta of all calibrated objects (identified electrons, muons, photons, hadronicdecays of ⌧-leptons, and jets) and an additional term for transverse energy in the calorimeter not includedin any of these objects [88]. Events must have Emiss
T > 150 GeV in order to suppress the background frommultijet events. To further suppress the multijet background, the two leading jets are required to have anazimuthal opening angle |�� j j| < 2.5 radians and an azimuthal opening angle with respect to the Emiss
Tof |�� j,Emiss
T| > 1.6 radians for the leading jet and |�� j,Emiss
T| > 1 radian otherwise. In the VBF process,
the forward jets tend to have large separations in pseudorapidity (�⌘ j j), with correspondingly large dijetmasses, and little hadronic activity between the two jets. To focus on the VBF production, the leading jetsare required to be well-separated in pseudorapidity |�⌘ j j| > 4.8, and have an invariant mass m j j > 1 TeV.Events are rejected if any jet is identified as arising from the decay of a b-quark or a ⌧-lepton. The rejectionof events with b-quarks suppresses top-quark backgrounds. Similarly, rejection of events with a ⌧-leptonsuppresses the W(! ⌧⌫)+jets background. Further, events are vetoed if they contain any reconstructedleptons passing the transverse momentum thresholds pe
T > 10 GeV for electrons, pµT > 5 GeV for muons,or p⌧T > 20 GeV for ⌧-leptons. Finally, events with a third jet having pT > 30 GeV and |⌘| < 4.5are rejected. The SR2 selections are motivated by a search for new phenomena in final states with anenergetic jet and large missing transverse momentum [25], and di↵er from those of SR1. First, the leadingjet4 is required to have pT > 120 GeV and |⌘| < 2.5. Additionally, the sub-leading jet is required to havepT > 35 GeV, the �� j j requirement is removed, the requirement on �� j,Emiss
Tis relaxed to |�� j,Emiss
T| > 0.5,
and the EmissT requirement is tightened to Emiss
T > 200 GeV. A common threshold of pT = 7 GeV isused to veto events with electrons and muons, and no ⌧-lepton veto is applied. Finally in SR2, the Emiss
Tcomputation excludes the muon contribution and treats hadronic taus like jets (this allows the modellingof W+jets and Z+jets in the control regions and signal regions using the same Emiss
T variable as discussedin Section 5). SR2 is further subdivided into SR2a with 500 < m j j < 1000 GeV, ⌘ j1 ⇥ ⌘ j2 < 0, and|�⌘ j j| > 3, and SR2b with m j j > 1000 GeV, ⌘ j1 ⇥ ⌘ j2 < 0 and 3 < |�⌘ j j| < 4.8.
4 The “charge fraction" of this jet is defined as the ratio of the ⌃pT of tracks associated to the jet to the calibrated jet pT; thisquantity must be at least 10% of the maximum fraction of the jet energy deposited in one calorimeter layer. The chargedfraction requirement was shown to suppress fake jet backgrounds from beam-induced e↵ects and cosmic-ray events [25].
6
CMS analysis is give in combined analysis
VBF H inv: Results and Limits • Results: SR1 (539 events) SR2 (3,290 events)
• BF(H->inv) limits:
04 April 2017 DM@LHC2017, UCI 15
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Figure 6: Data and MC distributions after all the requirements in SR1 for (a) EmissT and (b) the dijet invariant mass
mj j. The background histograms are normalized to the values in Table 8. The VBF signal (red histogram) isnormalized to the SM VBF Higgs boson production cross section with BF(H ! invisible) = 100%.
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Figure 7: Data and MC distributions after all the requirements in SR2 for (a) EmissT and (b) the dijet invariant mass
mj j. The background histograms are normalized to the values in Table 8. The VBF signal is normalized to the SMVBF Higgs boson production cross section with BF(H ! invisible) = 100%.
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Figure 6: Data and MC distributions after all the requirements in SR1 for (a) EmissT and (b) the dijet invariant mass
mj j. The background histograms are normalized to the values in Table 8. The VBF signal (red histogram) isnormalized to the SM VBF Higgs boson production cross section with BF(H ! invisible) = 100%.
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Figure 7: Data and MC distributions after all the requirements in SR2 for (a) EmissT and (b) the dijet invariant mass
mj j. The background histograms are normalized to the values in Table 8. The VBF signal is normalized to the SMVBF Higgs boson production cross section with BF(H ! invisible) = 100%.
16
Observed Expected 0.28 0.31
Dominant systematic errors: • Jet energy scale and resolution • Parton shower modeling
CMS limit is give in combined analysis
ggH inv: • CMS, 13 TeV, 12.9 fb-1 (arXiV:1703.01651[hep-ex]) • Re-interpretation of mono-jet and mono-V(hadronic) dark
matter search. • Details covered in mono-jet talk by Osamu Jinnouchi. • BF(H->inv) combined limits:
• ggH inv only limits:
04 April 2017 DM@LHC2017, UCI 16
18 7 Summary
is assumed to be the same as sSM, this limit can be used to constrain the invisible branchingfraction of the Higgs boson. The observed (expected) 95% CL upper limit on the invisiblebranching fraction of the Higgs boson, sB(H ! inv)/sSM, is found to be 0.44 (0.56). The limitsare summarized in Fig. 13. Table 3 shows the individual limits for the monojet and mono-Vcategories. While these limits on B(H ! inv) are not as strong as the combined ones fromRef. [36], they are obtained from an independent data sample and therefore will contribute tofuture combinations.
Table 3: Expected and observed 95% CL upper limits on the invisible branching fraction ofthe Higgs boson. Limits are tabulated for the monojet and mono-V categories separately, andfor their combination. The one standard deviation uncertainty range on the expected limits islisted. The signal composition in terms of gluon fusion, vector boson fusion, and an associatedproduction with a W or Z boson is also provided.
Category Expected Observed ±1 s.d. Expected signallimit limit composition
Mono-V 0.72 1.17 [0.51–1.02] 39.6% ggH, 6.9% VBF, 32.4% WH, 21.1% ZHMonojet 0.85 0.48 [0.58–1.27] 71.5% ggH, 20.3% VBF, 4.4% WH, 3.8% ZHCombined 0.56 0.44 [0.40–0.81] —
Monojet Mono-V Combined
SMσ
inv)
/→
x B
(H
σ95
% C
L up
per l
imit
on
0
0.5
1
1.5
2
2.5
sObserved CL
sMedian expected CL68% expected95% expected
(13 TeV)-112.9 fb
CMS
Figure 13: Expected (dotted black line) and observed (solid black line) 95% CL upper limits onthe invisible branching fraction of a 125 GeV SM-like Higgs boson. Limits are shown for themonojet and mono-V categories separately, and also for their combination.
7 SummaryA search for dark matter (DM) is presented using events with jets and large missing transversemomentum in a
ps = 13 TeV proton-proton collision data set corresponding to an integrated
luminosity of 12.9 fb�1. The search also exploits events with a hadronic decay of a W or Z bo-son reconstructed as a single large-radius jet. No significant excess is observed with respectto the standard model backgrounds. Limits are computed on the DM production cross section
Observed Expected 0.44 0.56
Combination of § ggHinv (mono-jet) § V(had)Hinv + VBF Hinv (mono-V)
Observed Expected 0.48 0.85
ggHinv
VH+VBF
ATLAS combined analysis • ATLAS, 4.7 (7 TeV) + 20.3 (8 TeV) fb-1 (arXiv:
1509.00672[hep-ex]) • Combination of 3 modes:
• VBF Hinv (shown above) • ZHinv leptonic (arXiv:1402.3244[hep-ex]). • ZHinv hadronic (shown above)
• BF(H->inv) limit = 0.25 • Further combining with visible decay modes:
• BF(H->inv) limit = 0.23
04 April 2017 DM@LHC2017, UCI 17
ATLAS combined: DM Limits • Higgs-portal dark matter (HàWIMP pair) limits
04 April 2017 DM@LHC2017, UCI 18
WIMP mass [GeV]1 10 210 310
]2W
IMP-
nucl
eon
cros
s se
ctio
n [c
m
57−10
55−10
53−10
51−10
49−10
47−10
45−10
43−10
41−10
39−10
DAMA/LIBRA (99.7% CL)CRESST II (95% CL)CDMS SI (95% CL)CoGeNT (99% CL)CRESST II (90% CL)SuperCDMS (90% CL)XENON100 (90% CL)LUX (90% CL)
Scalar WIMPMajorana WIMPVector WIMP
ATLAS
Higgs portal model:ATLAS 90% CL in
-1 = 7 TeV, 4.5-4.7 fbs-1 = 8 TeV, 20.3 fbs
Vis. & inv. Higgs boson decay channels]inv, BRγZκ, γκ, gκ, µκ, τκ, bκ, tκ, Zκ, Wκ[
<0.22 at 90% CLinv
assumption: BRW,ZκNo
Figure 9: ATLAS upper limit at the 90% CL on the WIMP–nucleon scattering cross section in a Higgs portal modelas a function of the mass of the dark-matter particle, shown separately for a scalar, Majorana fermion, or vector-boson WIMP. It is determined using the limit at the 90% CL of BRinv < 0.22 derived using both the visible andinvisible Higgs boson decay channels. The hashed bands indicate the uncertainty resulting from varying the formfactor fN by its uncertainty. Excluded and allowed regions from direct detection experiments at the confidencelevels indicated are also shown [119–127]. These are spin-independent results obtained directly from searches fornuclei recoils from elastic scattering of WIMPs, rather than being inferred indirectly through Higgs boson exchangein the Higgs portal model.
26
CMS combined analysis • CMS, 5.1 (7 TeV) + 19.7 (8 TeV) + 2.3 (13 TeV) fb-1 (arXiv:
1610.09218[hep-ex]) • Combination of 4 modes:
• VBFHinv, ZHinv leptonic, ZHinv bbbar (arXiv:1404.1344[hep-ex]) • VHinv dijet, ggHinv mono-jet (arXiv:1607.05764[hep-ex]) • Plus 13 TeV data.
• Event selection and background estimation for each mode are similar to other analysis:
04 April 2017 DM@LHC2017, UCI 19
VBF selection
CMS combined: 13 TeV Results • 13 TeV, 2.3 fb-1
results:
04 April 2017 DM@LHC2017, UCI 20
Mode Observed events
VBF 126 Z(ll) 0-jet 26 Z(ll) 1-jet 6 V(jj) ~30? Monojet ~2000?
CMS combined: Limits • BF(H->inv) combined limit
• VBF H inv limit can be read out from the plot
• Dominant systematic
uncertainties: • Lepton efficiency • W+jets/Z+jets ratio, theory
04 April 2017 DM@LHC2017, UCI 21
Observed Expected 0.24 0.23
Observed Expected 0.44 0.32
VBF H inv
Z(ll)+Z(bb)+V(jj)
Monojet
CMS combined: DM limits • Higgs-portal dark matter limits:
04 April 2017 DM@LHC2017, UCI 22
Conclusion • This table summarize current constraints on BF(H->inv)
from each channel and combined.
• Analysis with full 2016 dataset is on-going.
04 April 2017 DM@LHC2017, UCI 23
Mode ATLAS CMS
ZH inv leptonic 0.98 13.3 (13 TeV) fb-1 0.86 12.9 (13 TeV) fb-1
VH inv hadronic 0.78 20.3 (8 TeV) fb-1 n/a
ggH inv n/a 0.48 12.9 (13 TeV) fb-1
VBF H inv 0.28 20.3 (8 TeV) fb-1 0.44 5.1 (7 TeV) + 19.7 (8 TeV) + 2.3 (13 TeV) fb-1
Combined 0.23 4.7 (7 TeV) + 20.3 (8 TeV) fb-1
0.24 5.1 (7 TeV) + 19.7 (8 TeV) + 2.3 (13 TeV) fb-1
Paper references • arXiv:1606.02266[hep-ex] JHEP08(2016)045 • arXiv:1504.04324[hep-ex] Eur. Phys. J. C (2015) 75:337 • arXiv:1508.07869[hep-ex] JHEP 01 (2016) 172 • arXiV:1703.01651[hep-ex] Submitted to JHEP • arXiv:1509.00672[hep-ex] JHEP11(2015)206 • arXiv:1402.3244[hep-ex] Phys. Rev. Lett. 112, 201802
(2014) • arXiv:1610.09218[hep-ex] JHEP 02 (2017) 135 • arXiv:1404.1344[hep-ex] Eur. Phys. J. C 74 (2014) 2980 • arXiv:1607.05764[hep-ex] JHEP 12 (2016) 083
04 April 2017 DM@LHC2017, UCI 24
Backup: VBF H inv: Z(W)+jets background • Scale factors (signal region)/(control region) are derived
by MC. • (Signal region) = (scale factor)*(control region) • Z+jets control region: W+jets control region:
04 April 2017 DM@LHC2017, UCI 25
150 200 250 300 350 400 450 500
Even
ts/5
0 G
eV
-110
1
10
ll→Z
Other Backgrounds
Data
ATLAS
, 8 TeV-120.3 fb
SR1 Z Control Region
[GeV]missT
Emulated E150 200 250 300 350 400 450 500
Da
ta/M
C
00.5
11.5
2
Figure 2: Data and MC distributions of the emulated EmissT (as described in the text) in the SR1 Z(! ee/µµ)+jets
control region.
Even
ts
-210
-110
1
10
210
310
410 ll)+jets→Z(
Other Backgrounds
Data
ATLAS
, 8 TeV-120.3 fb ee Control Region→SR2 Z
[GeV]missT
Emulated E200 250 300 350 400 450 500
Data
/MC
0.5
1
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(a)
Even
ts
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-110
1
10
210
310
410 ATLAS
, 8 TeV-120.3 fb Control Regionµµ→SR2 Z
ll)+jets→Z(
Other Backgrounds
Data
[GeV]missTE
200 250 300 350 400 450 500
Data
/MC
0.5
1
1.5
(b)
Figure 3: Data and MC distributions of the EmissT (as described in the text) in the SR2 Z+jets control regions
(a) Z(! ee)+jets and (b) Z(! µµ)+jets.
10
0 20 40 60 80 100 120 140 160 180 200
Ev
en
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ll→ZOther
Data
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+SR1 WControl Region
[GeV]Tm0 20 40 60 80 100 120 140 160 180 200
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en
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, 8 TeV-120.3 fbν e→
-SR1 WControl Region
[GeV]Tm0 20 40 60 80 100 120 140 160 180 200
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0 20 40 60 80 100 120 140 160 180 200
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en
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310Multijets
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, 8 TeV-120.3 fbνµ →
+SR1 WControl Region
[GeV]Tm0 20 40 60 80 100 120 140 160 180 200
Da
ta/M
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(c)
0 20 40 60 80 100 120 140 160 180 200
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en
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ll→ZOtherData
ATLAS
, 8 TeV-120.3 fbνµ →
-SR1 WControl Region
[GeV]Tm0 20 40 60 80 100 120 140 160 180 200
Da
ta/M
C
00.5
11.5
2
(d)
Figure 4: The transverse mass distributions used in the SR1 W+jets control regions after all requirements exceptfor the Emiss
T > 150 GeV requirement: (a) W+ ! e+⌫, (b) W� ! e�⌫, (c) W+ ! µ+⌫ and (d) W� ! µ�⌫.
Ev
en
ts/2
0 G
eV
1
10
210
310
410Multi-jet
)+jetsν l→W(
ll)+jets→Z(
Other Backgrounds
Data
ATLAS
, 8 TeV-120.3 fbν e→SR2 W
Control Region
[GeV]Tm0 20 40 60 80 100 120 140 160 180 200
Da
ta/M
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Ev
en
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510)+jetsν l→W(
ll)+jets→Z(
Other Backgrounds
Data
ATLAS
, 8 TeV-120.3 fbνµ→SR2 W
Control Region
[GeV]Tm0 20 40 60 80 100 120 140 160 180 200
Da
ta/M
C
0.5
1
1.5
(b)
Figure 5: The transverse mass distributions in the SR2 W+jets control regions after all requirements: (a) W ! e⌫and (b) W ! µ⌫.
13
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