Jet energy correction (Zmumu, 10k)

June 4,2008 Jongseok Lee(Sungkyunkwan University)

1

# of jet

2

red : calojetgreen : genjetpt>15, ΔR(jet,mu)>0.5

Jet energy correction factor

3

PT(calojet)

factor

Matching jet with MC μ

4

ΔR

(gen

jet,

mcm

u)

PT(genjet)/PT(mcmu)

ΔR

(corj

et,

mcm

u)

PT(corjet)/PT(mcmu)

ΔR

(gen

jet,

mcm

u)

ΔR

(corj

et,

mcm

u)

PT(genjet)/PT(mcmu) PT(corjet)/PT(mcmu)

no cut no cut

pt>15 pt>15

nConstituent

5

no corrected nCpt>15

no corrected nCpt>15ΔR(jet,mcmu)>0.5

red : corjet, black : genjet

corrected nCpt>15

corrected nCpt>15ΔR(jet,mcmu)>0.5

Average PT of jet tower

6

corrected nCpt>15

corrected nCpt>15ΔR(jet,mcmu)>0.5

red : corjet, black : genjet

# of jet

7

pt>15, ΔR(jet,mu)>0.5

pt>15

pt>15, nC>=5, ΔR(jet,mu)>0.5

pt>15, nC>=5

red : corjet, black : genjet

PT

8

red : corjet, black : genjet

pt>15, ΔR(jet,mu)>0.5

pt>15

pt>15, nC>=5, ΔR(jet,mu)>0.5

pt>15, nC>=5

η

9

red : corjet, black : genjet

pt>15, ΔR(jet,mu)>0.5

pt>15

pt>15, nC>=5, ΔR(jet,mu)>0.5

pt>15, nC>=5

Jet efficiency (corjet/genjet)

10

pt>15, ΔR(jet,mu)>0.5

pt>15, ΔR(jet,mu)>0.5

pt>15

pt>15

black : pt>15, ΔR(jet,mu)>0.5red : pt>15

black : pt>15, ΔR(jet,mu)>0.5red : pt>15

back up

11

Jet energy correction factor

12

Many reasons why a calorimeter jet energy differs

from anunderlying particle and parton jet energies:

Energy offset due to electronics noise and event pile-up

Energy lost due to energy thresholds applied at cell and

tower level

Energy lost due to particles bent away in 4T magnetic field

Nonlinear HCAL response (e/h < 1)