TWiki> CMS Web>NewPhysics>CmsSusy>CMSSusyAnalysisResults (revision 21)EditAttach

Information

Analysers:

  • Janos Karancsi - PhD student (ATOMKI & UNIDEB, Debrecen, HU)
  • Viktor veszpremi - PhD (Wigner, Budapest, HU)
  • Petar Maksimovic - Prof. PhD (Johns Hopkins University, Baltimore, US)
  • Brandon Chiarito - Student (Johns Hopkins University, Baltimore, US)

Links:

For a lot of results we share a common elog with the JHU group: JHU elog

Twikis:

Useful info:

Papers, Notes:

Links Date Author Title Comment
arXiv:physics/0308063 2003 G. Punzi Sensitivity of searches for new signals and its optimization
CMS PAS JME-09-001 2009 CMS A Cambridge-Aachen (C-A) based Jet Algorithm for boosted top-jet tagging
arXiv:1011.2268 2010 J. Thaler, K. V. Tilburg Identifying Boosted Objects with N-subjettiness tau variables (N-sj.), Mistag rates, tagging efficiencies
arXiv:1006.2833 2010 T. Plehn et. al Stop Reconstruction with Tagged Tops
CMS-PAS-B2G-12-006 (Twiki) 2013 CMS Search for Anomalous Top Quark Pair Production in the Boosted All-Hadronic Final State Mistag rate of top tagging algo, Multijet bkg estimation
CMS-PAS-B2G-12-006 (Twiki) 2013 CMS Search for ttbar resonances in semileptonic final state 2D cut for semi-leptonic top
CMS-PAS-JME-13-007 2014 february CMS Boosted Top Jet Tagging at CMS
SUS-14-007 (Approval) 2015 Razor group Search for SUSY with boosted W's using the razor variables

Presentations:

Important results

Links to latest results

Object/Event selections

Object definitions

All objects come from MiniAOD slimmed Pat collections: MiniAOD objects

Jets
Anti-kt algorithm jets with cone size: R=0.8, B2G baseline cuts:
  • pT > 100 GeV /c
  • | eta | < 4

Electrons
gedGsfElectrons with cuts (B2G baseline: pT > 30 GeV /c, |eta | < 2.5):
  • pT > 35 GeV /c
  • | eta | < 2.5

Muons
muons with cuts (B2G baseline: pT > 30 GeV /c, |eta | < 2.5)
  • pT > 45 GeV /c
  • | eta | < 2.1
  • tight ID

MET
type1 PF MET

Event Selection
Exactly 2 AK8 Jets with cuts (loose hadronic top selection):
  • pT > 400 GeV /c
  • tau3 / tau2 < 0.75
  • Pruned Mass > 140 Gev/c^2
Signal selection cuts (See below)
  • R (Razor variable) - Recipe
    • Calculated for jets with | eta | < 3
  • H_T,all = Sum ( AK8Jet pT ) + Sum ( Lepton pT ) + MET
  • DPhi = | DeltaPhi ( top_had1, top_had2 ) |

Signal Selection

Cut flow chart

Best cuts using Smin maximisation script - New
  • 2 Hadronic tops
  • Loose lepton veto

Maximum Smin, for all combination of cuts:

Best cut T5ttttDeg 4bodydec mGo1300 T5ttttDeg 3bodydec mGo1300 QCD_HT QCD_Pt bcToE TTBar GJets_HT WJets_HT T_tW TToLep_s_t ZJets_HT DYJets_HT All bg Smin = Eff./(5/2+sqrt(B))
No cut 16.46 16.81 13569.47 44965.06 5257.04 194.89 35.20 49.68 1.72 6.81 4.32 64084.20 0.00391
HTall>2550 4.64 4.20 374.39 0.00 312.57 10.38 3.48 3.57 0.00 0.74 0.29 705.42 0.00861
DPhi<1.6 3.09 3.06 54.46 0.00 158.98 1.30 0.25 2.15 0.00 0.15 0.05 217.34 0.01055
R>0.44 7.99 7.36 0.00 0.00 2.69 0.00 0.35 0.00 0.00 0.14 0.03 3.22 0.10194
DPhi<2.7 && HTall>2100 7.64 6.74 197.41 0.00 301.79 5.53 1.77 2.86 0.00 0.47 0.18 510.00 0.01598
R>0.44 && HTall>1200 7.98 7.36 0.00 0.00 2.69 0.00 0.35 0.00 0.00 0.14 0.03 3.22 0.10194
R>0.35 && DPhi<2.8 10.02 9.84 0.00 0.00 0.00 0.05 0.61 0.00 0.00 0.32 0.02 1.00 0.16734
R>0.32 && DPhi<2.8 && HTall>1450 10.51 10.18 0.00 0.00 0.00 0.05 0.66 0.00 0.00 0.36 0.01 1.08 0.17126

Using cuts:

  • R > 0.4
  • DPhi < 2.8

Manual cuts are ( R > 0.4 && DPhi < 2.8 && HTall > 0 )

Cut T5ttttDeg 4bodydec mGo1300 T5ttttDeg 3bodydec mGo1300 QCD_HT QCD_Pt bcToE TTBar GJets_HT WJets_HT T_tW TToLep_s_t ZJets_HT DYJets_HT All Background Smin = Eff./(5/2+sqrt(B))
No Cut 16.46 16.81 13569.47 44965.06 5257.04 194.89 35.20 49.68 1.72 6.81 4.32 64084.20 0.00391
DPhi<2.8 12.74 12.72 1344.02 2569.43 1158.65 21.35 5.30 9.26 0.00 1.52 0.57 5110.10 0.01023
R>0.4 9.26 8.72 0.00 0.00 13.47 0.05 0.61 0.36 0.00 0.29 0.04 14.82 0.08175
R>0.4 && DPhi<2.8 8.81 8.40 0.00 0.00 0.00 0.05 0.45 0.00 0.00 0.19 0.01 0.71 0.14960

Background Estimation

Signal selection cuts:

  • 2 Hadronic tops
  • Loose lepton veto
  • R > 0.4
  • DPhi < 2.8

Introducing the method

ABCD Method:
  • Define NTop<2 sideband, where the sideband is defined as 2 loose top-like jets:
    • Has at least 2 AK8 jets with pt > 400, prunedMass > 100
    • Sideband cut: NTopHad < 2
  • Measure event yields in the R<0.4 sideband both for A) NTop<2 and C) NTop==2
  • Fit NTop<2 sideband (A, B) with an exponential decay curve: exp(const + x * slope)
    • Extract fit parameters and their error: const, slope
  • Scale function by the event yield ratio C/A to get Signal region prediction: D

Recipe to plot very similar distributions by hand (for leading and subleading jets): 

root -l
TChain c("c");
c.Add("/data/gridout/jkarancs/SusyAnalysis/B2G/TTreeNtuple/Feb28_edm_Feb20/WJetsToLNu_HT-600toInf/*.root/B2GTTreeMaker/B2GTree");
c.Draw("evt_R","jetAK8_Pt[0]>400&&jetAK8_Pt[1]>400&&jetAK8_prunedMass[0]>100&&jetAK8_prunedMass[1]>100&&evt_NTopHad<2");
c.Draw("evt_R","evt_NTopHad==2","SAME")
c.Draw("evt_R","evt_NTopHad==2&&evt_TTHadDPhi<2.8","SAME")

Plots - Extrapolation of R shape using an exponential fit in the NTop<2 SideBand

TTbar QCD Comment
R shape fit with exponential in the Ntop<2 sideband and NTop==2 signal bands. Range [0.15,1.0] for sideband, [0.15,0.4] for signal band.
W+Jets Z+Jets --> NuNu Comment
R shape fit with exponential in the Ntop<2 sideband and NTop==2 signal bands. Range [0.15,1.0] for sideband, [0.15,0.4] for signal band, except for WJets for which low range is 0.2.
G + Jets Single top (tW channel) Comment
R shape fit with exponential in the Ntop<2 sideband and NTop==2 signal bands. Range [0.15,1.0] for sideband, [0.15,0.4] for signal band.
DY + Jets Comment
R shape fit with exponential in the Ntop<2 sideband and NTop==2 signal bands. Range [0.15,1.0] for sideband, [0.15,0.4] for signal band.

Table

To see how much background is there with given statistics:
  • No lepton veto applied
  • For TTBar and QCD, Sideband is in the DPhi>2.8 region instead of NTop<2

Sample A (R<0.4, Sideband) B (R fit in Sideband) pred. B (R>0.4, Sideband) C (R<0.4, Signal band) D (R fit in C) pred. D = B*C/A pred. D = B (R fit in Sideband) * C/A D (R>0.4, Signal band) obs. Nevent in D
TTBar 5914.51 +- 126.24 22.07 +- 2.50 43.11 +- 10.78 1678.70 +- 67.26 3.16 +- 1.05 12.24 +- 3.11 6.26 +- 0.76 2.69 +- 2.69 1
WJets_HT 623.37 +- 5.61 39.91 +- 4.54 38.43 +- 1.39 13.69 +- 0.83 1.14 +- 1.67 0.84 +- 0.06 0.88 +- 0.11 0.86 +- 0.21 17
ZJets_HT 71.62 +- 0.81 15.56 +- 3.38 17.16 +- 0.40 1.43 +- 0.11 0.41 +- 1.50 0.34 +- 0.03 0.31 +- 0.07 0.27 +- 0.05 29
QCD_HT 13412.90 +- 302.17 0.90 +- 0.12 0.00 +- 0.00 1493.78 +- 100.84 0.29 +- 0.18 0.00 +- 0.00 0.10 +- 0.01 0.00 +- 0.00 0
T_tW 395.02 +- 11.84 5.26 +- 1.51 7.16 +- 1.59 14.64 +- 2.28 0.15 +- 1.40 0.27 +- 0.07 0.19 +- 0.06 0.00 +- 0.00 0
DYJets_HT 160.98 +- 0.88 0.27 +- 0.24 0.79 +- 0.06 3.92 +- 0.14 0.00 +- 0.02 0.02 +- 0.00 0.01 +- 0.01 0.01 +- 0.01 2
SUM 20578.41 +- 327.74 83.97 +- 6.37 106.65 +- 10.99 3206.15 +- 121.23 5.15 +- 2.85 13.71 +- 9.68 7.75 +- 0.78 3.83 +- 2.70 49

Below test of clusure with slightly relaxed R cut:

  • R cut is relaxed to > 0.35

Sample A (R<0.4, Sideband) B (R fit in Sideband) pred. B (R>0.4, Sideband) C (R<0.4, Signal band) D (R fit in C) pred. D = B*C/A pred. D = B (R fit in Sideband) * C/A D (R>0.4, Signal band) obs. Nevent in D
TTBar 5863.31 +- 125.69 53.73 +- 4.96 94.31 +- 15.94 1665.22 +- 66.99 8.38 +- 2.27 26.78 +- 4.69 15.26 +- 1.57 10.78 +- 5.39 4
WJets_HT 595.03 +- 5.48 61.78 +- 5.99 63.43 +- 1.79 13.33 +- 0.82 1.66 +- 2.04 1.42 +- 0.10 1.38 +- 0.16 1.26 +- 0.25 25
ZJets_HT 63.04 +- 0.76 23.05 +- 4.25 25.43 +- 0.48 1.28 +- 0.11 0.59 +- 1.56 0.52 +- 0.05 0.47 +- 0.10 0.40 +- 0.06 43
QCD_HT 13412.90 +- 302.17 4.21 +- 0.44 0.00 +- 0.00 1493.78 +- 100.84 1.10 +- 0.57 0.00 +- 0.00 0.47 +- 0.06 0.00 +- 0.00 0
T_tW 388.23 +- 11.74 10.33 +- 2.46 12.16 +- 2.08 14.64 +- 2.28 0.31 +- 2.45 0.46 +- 0.11 0.39 +- 0.11 0.00 +- 0.00 0
DYJets_HT 160.12 +- 0.88 0.72 +- 0.52 1.55 +- 0.09 3.90 +- 0.14 0.01 +- 0.04 0.04 +- 0.00 0.02 +- 0.01 0.03 +- 0.01 6
SUM 20482.65 +- 327.52 153.83 +- 9.22 196.88 +- 16.18 3192.16 +- 121.08 12.04 +- 4.25 29.22 +- 22.01 17.99 +- 1.59 12.47 +- 5.40 78

Main backgrounds identified on tested samples - TTBar, QCD, W+Jets

http://hep.pha.jhu.edu:8080/susy/230

QCD background estimation technique

http://hep.pha.jhu.edu:8080/susy/115

Estimation of Uncertainties

-- JanosKarancsi - 2015-02-26

Attachments Attachments
Topic attachments
I Attachment History Action Size Date Who Comment
Pngpng R_NTopHad_DPhiBelow2p8_DYJets_HT.png r1 manage 14.1 K 2015-03-14 - 14:53 JanosKarancsi  
Pngpng R_NTopHad_DPhiBelow2p8_GJets_HT.png r1 manage 14.1 K 2015-03-14 - 14:53 JanosKarancsi  
Pngpng R_NTopHad_DPhiBelow2p8_QCD_HT.png r1 manage 15.0 K 2015-03-14 - 14:54 JanosKarancsi  
Pngpng R_NTopHad_DPhiBelow2p8_TTBar.png r1 manage 14.0 K 2015-03-14 - 14:54 JanosKarancsi  
Pngpng R_NTopHad_DPhiBelow2p8_T_tW.png r1 manage 14.7 K 2015-03-14 - 14:54 JanosKarancsi  
Pngpng R_NTopHad_DPhiBelow2p8_WJets_HT.png r1 manage 14.3 K 2015-03-14 - 14:54 JanosKarancsi  
Pngpng R_NTopHad_DPhiBelow2p8_ZJets_HT.png r1 manage 14.1 K 2015-03-14 - 14:54 JanosKarancsi  
Pngpng R_NTopSideBand_WJets_Ht600.png r1 manage 26.4 K 2015-03-11 - 11:26 JanosKarancsi  
Pngpng R_NTopSideBand_ZJetsToNuNu_Ht600.png r1 manage 19.7 K 2015-03-11 - 11:26 JanosKarancsi  
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Topic revision: r21 - 2015-03-29 - JanosKarancsi
 
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