Top -> l+jets @ 10 TeVUpdates on Efficiencies and Event

Shapes

Xiaowen Lei, Ken Johns, Venkat Kaushik

(U. Arizona)

Outline

Top with C++ ARA Redesign of code

Update on efficienciesUpdate on likelihood study

Analysis redone with bug-fixed Wjets sample; results look reasonable

TMVA approach

Started Muon Isolation Study

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Top with C++ ARAARATopAnalysis package developed by

Venkat is committed into the Arizona group cvs area

http://atlas-sw.cern.ch/cgi-bin/viewcvs-atlas.cgi/groups/Arizona/ARATopAnalysis/

ARATopAnalysis package provides the following Steering base class with common functions A default steering class with default selectors

Analysis in this talk was done by selection routines written by user (not the default ones)

Configuration and messaging service Scripts and executables for submitting jobs to

pandaAdditional details is available on twiki

https://twiki.cern.ch/twiki/bin/view/Sandbox/VKaushikSandbox#ARATopAnalysis

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ARATopAnalysis

Top with C++ ARASteering in ARATopAnalysis is used nowAnalysis methods are rewritten to separate

classes They serve as the user-implemented

“selectors” (processors)Helper classes for “communication”

between the processors are added. Selected objects are stored in

mySelectedObjects Event weights, trigger information, as well as

the cut bits are stored in myEventInfoRewrote the class for calculating

topological variables. Fixed some mistakes. Now it’s ready to be put into cvs

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Changes to the user analysis code

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EfficienciesLepton+jets selection efficiencies

were updated Weights are properly included Corrected W+jets samples are used

E368_s463_r563 Began processing smaller background samples

Updated samples include Wenu+Np: 108241, 108242, 108243; Wmunu+Np:

108245, 108246, 108247 Single top: 108240(schan_enu),

108241(schan_munu), 108243(tchan_enu), 108244(tchan_munu)

Tables are on the twiki page https://twiki.cern.ch/twiki/bin/viewauth/AtlasProtected/

TopCSBenchMark#Single_lepton_channel

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Cuts from the Spreadsheet Cut 1 – lepton trigger

EF_e20i or EF_mu20 Cut 2 – exactly 1 (medium) lepton with Pt>20GeV

For electron require isem(egammaPID::ElectronLoose) ==0 |eta|<2.5 && !(1.37<eta<1.52) etcone20<6GeV

For muon require |eta|<2.5 etcone20<6GeV

Note for muon, for the mc08 data, isolation is shifted down

etcone40 returns energy in cone with radius 0.3 should probably correct for it

Cut 3 – MET>20GeV Cut 4 – 4 good jets with Pt>30GeV Cut 5 – 3 good jets with Pt>40GeV Cut 6 – 150<m_jjj<190GeV

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e+jet Efficiencies

EfficienciesMC sample # Evt Cut 1 Cut 1-2 Cut 1-3 Cut 1-4 Cut 1-5 Cut 1-6

105200 55298 13861 9966 9016 2970 2558 611

105204              

105205              

105206 108396 29284 21348 18732 6510 5628 1460

               

108240              

108241 23980 13018 10504 8820 111 78 11

108242 8500 4240 3420 2905 340 270 27

108243 3000 1357 1075 912 311 263 25

               

108340 10808 6186 5161 4561 73 68 8

108342              

108343 2858 1505 1224 1091 37 28 2

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mu+jet Efficiency

Efficiencies

MC sample events cut 1 cut 1-2 cut 1-3 cut 1-4 cut 1-5 cut 1-6

105200 55298 14685 11850 10784 3745 3216 781

105204              

105205              

105206 108396 30428 24925 22124 7894 6820 1791

               

108244              

108245 10500 5394 5250 4570 143 102 18

108246 6313 3193 3102 2708 496 385 52

108247 3000 1594 1543 1365 563 468 44

               

108341 11039 6243 6009 5382 58 45 7

108342              

108344 8065 4516 4314 3855 150 115 16

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Topological Variables Analysis was redone with corrected W+jets

samples (e368_s462_r563) As a first step, used only 8242 (Np4) for Wenu+jets

and 8246(Np4) for Wmunu+jets Repeated our previous analysis to see if it works

No further optimization of the likelihood is done yet

Use events which passed cuts 1-5 A total number of 12 transformed variables are

currently used See following slides for plots of topological varialbes and

template functions

TMVA approach TMVA seems to be a good tool for optimizing the

likelihood

Topological Variables – mu+jetslog(ht):

sum(et) for jets et>15GeV

log(ht_2):log(et_j1+et_j2)

log(ht_3):log(et_j3+et_j4)

log(ht’_2):log(Sum(et)_j234/

Sum(pz)_j1234)

log(he) is also used but not shown here

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Topological Variables – mu+jets

log(centrality):log(ht/he)To remove?

exp(-11apla):apla = 3/2Q_1

log(sphe):sphe =

3/2(Q_1+Q_2)

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Topological Variables – mu+jetsLog(mjj_min):

minimum dijet mass

Use 4 leading jets

dPhi:angle between

leading lepton and missing et

log(K’_Tmin):minimum dijet

distance * et of the lower in the pair / hadronic W et

masschisq12

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Topological Variable Fits – mu+jets

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Topological Variable Fits – mu+jets

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Topological Variable Fits – mu+jets

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Topological Likelihood Lt

e+jets:

mu+jets:

Study with TMVA Get similar comparison plots and likelihood plots. TMVA

also give extra outputs which I am learning to understand TMVA is nice because it gives correlation between

variables. It can also be easily configured to use diferent variables

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Muon Isolation We started looking at muon isolation

As a first step we compared etcone20 (cone size 0.1) of ttbar (105200) and bbmu15X (108405)

No cuts on muons We are still at a very initial stage but plots can be

easily added and quickly produced A few things on our to-do list:

Compare etcone for different cone sizes. Also need to compare different inner cone sizes

Come up with cuts to extract the signal (muon from W)

Need to add cuts and change to log scale to see more clearly

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Conclusions Conclusions

We changed our C++ ARA code into a better design The code is ready to be put into cvs

We updated lepton+jets efficiency tables for bug-fixed W+jets samples and single-top samples

We redid our likelihood analysis with the new W+jets sample

Background still has low statistics We tried the same likelihood analysis with TMVA

Looked at the correlation matrix We made preliminary plots for muon isolation study

To-Do List To-do list:

We need to take into account the problem of shifted muon isolation

Since Atlfast samples for W+jets are available now (e368_a68), we can use them to increase the background statistics

Next we will consider single top as a background in our likelihood study

TMVA seems to be a nice tool for optimizing likelihood analysis. We want to use it to:

Try different combination of the variables Study the correlation between the variables

We would like to continue with muon isolation study

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