Alpgen MC Samples

Jet Flavour Identifier

Lepton ID Plots

Alpgen Settings for CMS

Alpgen v2.05 CMS Default kinematic cuts in Alpgen

Pt(l,c,b) > 20 GeV |eta (j,c,b)| < 5.0 |eta(e,mu,tau)| < 3.0 dR(jj)>=0.7 dR(lj)>=0.0 M_top = 175 GeV

Alpgen Data Samples

W+NJets Wbb+NJets Z+NJets Zbb+NJets (running & failing on grid) WW/WZ/ZZ

Jet Multiplicity

Hard process has to be showered. Afterwards two possible modes:

Inclusive: Events with extra Jets due to the parton shower are kept.

Exclusive: Events with extra jets are rejected. For a exclusive sample set the one with the

highest jet mulitplicity must be a inclusive sample

Cuts in Event Selection

Electron |eta| < 2.4 Pt > 26 GeV

Muon |eta| < 2.1 Pt > 19 GeV

TQAF ID LeptonID >= 1 Track Isolation < 0.1 Likelihood Ratio > 0.5

Jets |eta| < 5 Pt > 30 GeV btag > 0.54 MET > 30

Selection Efficiency W+Jets

W+0 Jets W+1Jet W+2 Jets W+3 Jets W+4 Jets W+5 Jets W+6 Jets

Cross section [pb] 30 000 8 000 2 500 722 174 45 31

Total Events 195 933 191 966 180 937 50 199 72 585 55 209 19 619

2 Jet Bin 3 814 36 005 82 848 22 885 11 520 3 146 155

After Cuts:

All 6 36 808 252 150 53 3

Barrel Electrons 1 3 208 59 38 15 0

Endcap Electrons 1 2 64 28 16 11 1

Muons 4 31 536 165 96 27 2

Efficiency [%] 0.0031 0.019 0.45 0.50 0.21 0.096 0.015

JetslJetsWqq '

Jet Flavour Identifier

Algorithmic Definition Physics Definition

JFI – Algorithmic Definition

Find Parton that most likely determines the properties of the jet and assign its flavour as the “true” jet flavour

If b or c quark matches to jet cone (ΔR < 0.3) label jet as b or c jet

Else assign flavour of hardest parton to the jet

JFI – Physics Definition

Match reco jet to initial partons from primary process with ΔR < 0.3

No matching if hard final state radiation changes the parton direction significantly

No flavour assignement if matching is ambigous: >1 initial partons match the jet

Gluon jets splitting to c or b quarks are labeled as gluon

Jet Flavour in W+Jets

0 1 2 3 4 5 6

uds 56.1 57.4 49.4 44.0 40.3 37.6 33.5

c 0.8 12.9 10.9 9.8 8.5 7.7 6.8

b 0 0.2 0.6 0.9 1.1 1.5 2.1

g 43.1 29.4 39.1 45.2 50.1 53.3 57.6

W+Jets Pretag Sample TQAF uses Algorithmic Definition all jets in the events after preselection

Selection Efficiency Wbb+Jets

Wbb+2 Jets Wbb+3 Jets

Cross section [pb] 100

Total Events 147 894 22 982

2 Jet Bin 14 322 788

After Cuts:

All 768 40

Barrel Electrons 199 14

Endcap Electrons 90 3

Muons 479 23

Efficiency [%] 0.52 0.17

JetsbblJetsbbWqq '

Wbb+0/1 Jets not available yet

Selection Efficiency Z+Jets

Z+0 Jets Z+1Jet Z+2 Jets Z+3 Jets Z+4 Jets Z+5 Jets Z+6 Jets

Cross section [pb] 2 436 670 230 66 17 4 3

Total Events 43 814 47 869 46 560 47 913 21 402 4 779 4 185

2 Jet Bin 5 267 12 390 19 310 13 018 2 657 209 26

After Cuts:

All 1 31 86 81 25 5 1

Barrel Electrons 1 12 20 19 4 1 0

Endcap Electrons 0 5 6 10 2 0 0

Muons 0 14 60 52 19 4 1

Efficiency [%] 0.0023 0.065 0.18 0.17 0.12 0.10 0.024

JetsllJetsZqq 0

Selection Efficiency Di-Boson

WW (?) WZ ZZ

Cross section [pb] 10.5 4.3 2.6

Total Events 230 959 200 000 69 478

2 Jet Bin 72 601 59 631 20 239

After Cuts:

All 461 530 65

Barrel Electrons 126 148 14

Endcap Electrons 42 51 5

Muons 293 331 46

Efficiency [%] 0.20 0.27 0.094

llxZW llxZZ llWW

Selection Efficiency

tt Single top

Cross section [pb] 833 250

Total Events 2 732 326 192 400

2 Jet Bin 189 519 85 845

After Cuts:

All 42 463 12 845

Barrel Electrons 13 277 4 074

Endcap Electrons 2 707 795

Muons 26 479 7 976

Efficiency [%] 1.55 6.68

Track Probability Jet Tags Distribution

Peaks stem from bug in CMSW 1.3.6 algorithm. Fixed in CMSSW >= 1.5X

Lepton ID - ElectronsTQAF 136 070822 TQAF 136 071018

55 30245 978

55 209

45 978

Likelihood Ratio - ElectronsTQAF 136 070822 TQAF 136 071018

55 30245 978

55 209

45 978

Likelihood Ratio - Muon

11 50252 321

11 502

52 321

Track Isolation - ElectronsTQAF 136 070822 TQAF 136 071018

55 30245 978

55 209

45 978

Track Isolation - MuonTQAF 136 070822 TQAF 136 071018

52 32111 502

52 32111 502