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Update on Z(μμ)ϒ

Liang HAN, Liang HE, Suen Hou, Minghui LIU,Hongye SONG IPAS&USTC

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Data and MC comparison

Data: Period D-M (2701 events)

MC:Z+ϒ sample : mc11_7TeV.126016.Sherpa_Zmumugamma_1jetZ+jet sample:

mc11_7TeV.117661.AlpgenPythiaZmumuNp0/1/2/3/4/5_pt20

1.Compare MC Vs. data2.Estimate jet background

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Period #

D 112

E 27

F 86

G 279

H 167

I 203

J 134

K 331

L 799

M 563

Total 2701

MC(S+B) 2512.0+308.7

Event Selection of Period D-M

*1.Signal MC using MCFM NLO cross-section;*2. Background MC using data matrix method estimation;

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Gamma pT region

# uncertainty

(15,20) 958 0.0323(20,25) 611 0.0405(25,30) 332 0.0549(30,40) 350 0.0535(40,60) 257 0.0624

(60,100) 149 0.0819(100,200) 44 0.1508

Total Event in Each pT_ϒ bins

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pT_ϒ

dR(lϒ)

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pT_leading μ

pT_subleading μ

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InvMass of μμϒ

InvMass of μμ

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{ 𝑁 𝐿𝑜𝑜𝑠𝑒=𝑁 𝑠+𝑁 𝑏

𝑁 h𝑇𝑖𝑔 𝑡=𝜀𝑠❑𝑁 𝑠+𝜀𝑏

❑𝑁 𝑏

NLoose : photon pass 12 Tight shower shape

NTight : photon pass 12 Tight shower shape + Econe30t<6GeV

εs : make use of FSR photon muon stream sampleM(ll)<83GeV && 80GeV<M(llϒ)<96GeV

εb : get from dijet jet trigger sample W,Z vetoFind EM object back to back a jetpassT8 Reverse T4 (Anti-Tight)

Z+jet background estimation

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Z+jet background estimation

{ 𝑁 𝑙𝑜𝑜𝑠𝑒=𝑁 𝑠+𝑁 𝑏

𝑁 h𝑇𝑖𝑔 𝑡=𝜀𝑠❑𝑁 𝑠+𝜀𝑏

❑𝑁 𝑏

2939

2701

0.9944

0.5787

** 308.7

Loose

Tight

s

b

Loose Tights

b bs b

N

N

N NN

Uncertainty is still a work in progress

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