Update on Z+jets cross section at 8TeV &

First look at Z+Jets double differential cross sections, dsigma/dpTdy, at 8 TeV

Buğra BilinMETU

Kittikul Kovitanggoon, Sung-Won LeeTexas Tech

Efe YazganUniversity of Ghent

2

Datasets

/*/Run2012A − 13Jul2012 − v 1/*/Run2012A −recover – 6Aug2012 – v1/*/Run2012B − 13Jul2012 − v 1/*/Run2012C − 24Aug 2012 − v 1*/Run2012C –EcalRecover –11Dec2012 – v1 /*/Run2012C − Prompt − v 2/*/Run2012D − Prompt − v 1

Datasets of 2012 *: DoubleMu(DoubleElec)

JSON from https://twiki.cern.ch/twiki/bin/viewauth/CMS/PdmV2012Analysis

Cert_190456-196531_8TeV_13Jul2012ReReco_Collisions12_JSON_v2.txtCert_190782-190949_8TeV_06Aug2012ReReco_Collisions12_JSON.txtCert_198022-198523_8TeV_24Aug2012ReReco_Collisions12_JSON.txtCert_190456-203002_8TeV_PromptReco_Collisions12_JSON_v2.txtCert_201191-201191_8TeV_11Dec2012ReReco-recover_Collisions12_JSON.txtCert_190456-208686_8TeV_PromptReco_Collisions12_JSON.txt

MC

Total Lumi:19.626 fb-1

All plots normalized to integrated luminosity

NO QCD BACKGROUND ESTIMATION YET

Cross Check Study on Central Z Jet x-sec measurement

4

Selections Triggers

HLT_Mu17_Mu8_v*HLT_Mu17_TkMu8_v*

Muon

Muon matched trigger objectsMuon pT > 20 GeV and |Muon eta| < 2.4Opposite charge muonsTight Muon ID from Muon POGLoose PF base Combined relative ISO from Muon POGZ mass window of 71 to 111 GeV

Jets

Loose Jet ID from POGTight jet PU MVAPFNo Pileup (Charge Hadron Subtraction)Jet pT > 30 GeV|Jet eta| < 2.4Clean Jets from leptonswith DeltaR<0.5

MC is ID, Iso,and trigger efficiency corrected. Official PU reweighting is used.

• Electrons

Elec matched trigger objectsElec pT > 20 GeV and |Elec eta| < 2.4Opposite charge electronsMedium Electron IDEA Corrected PF ISO < 0.152012 EA’s usedZ mass window of 71 to 111 GeV

HLT_Ele17_CaloIdT_CaloIsoVL_TrkIdVL_TrkIsoVL_Ele8_CaloIdT_CaloIsoVL_TrkIdVL_TrkIsoVL*

5

Z mass

Njet

≥0 Njet

≥0

Z Properties

Muon Channel Elec Channel

6

Z phi

Njet

≥0 Njet

≥0

Z Properties

Muon Channel Elec Channel

7

Z pT

Njet

≥0 Njet

≥0

Z Properties

Muon Channel Elec Channel

8

Z Y

Njet

≥0 Njet

≥0

Z Properties

Muon Channel Elec Channel

9

Jet Multiplicity

Central region (|jet η| <2.4 )

Muon Channel Elec Channel

10

Leading jet in Central (|jet η| <2.4 )

Leading Jet pT Njet≥1

Muon Channel Elec Channel

11

SubLeading jet in Central (|jet η| <2.4 )

2nd Leading Jet pT Njet≥1

Muon Channel Elec Channel

12

Unfolding

Exclusive jet mult. (|jet η| <2.4 )

Muon Channel Elec Channel

13

Unfolding

Central region (|jet η| <2.4 )

Muon Channel Elec Channel

First Look to 2D x-sec measurement

15

Selections Triggers

HLT_Mu17_Mu8_v*HLT_Mu17_TkMu8_v*

Muon

Muon matched trigger objectsMuon pT > 20 GeV and |Muon eta| < 2.4Opposite charge muonsTight Muon ID from Muon POGLoose PF base Combined relative ISO from Muon POGZ mass window of 71 to 111 GeV

Jets

Loose Jet ID from POGTight jet PU MVAPFNo Pileup (Charge Hadron Subtraction)Jet pT > 30 GeV|Jet eta| < 4.7Clean Jets from leptonswith DeltaR<0.5

MC is ID, Iso,and trigger efficiency corrected. Official PU reweighting is used.

• Electrons

Elec matched trigger objectsElec pT > 20 GeV and |Elec eta| < 2.4Opposite charge electronsMedium Electron IDEA Corrected PF ISO < 0.152012 EA’s usedZ mass window of 71 to 111 GeV

HLT_Ele17_CaloIdT_CaloIsoVL_TrkIdVL_TrkIsoVL_Ele8_CaloIdT_CaloIsoVL_TrkIdVL_TrkIsoVL*

Jet PT

Muon Channel Elec Channel

Muon Channel Elec Channel

Jet eta

CONCLUSIONS

-> Added PFNoPileUp to the seuence.

-> The general distributions are in agreement with Tomislav et. al.’s results

-> Working on unfolding as support & cross check.

-> First distributions regarding the 2D measurement shown.

->We will proceed to Unfolding.

->We have to understand the forward jets better.