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Update the rho correction of photon isolation using linear and quadratic Effective area values from Egamma for Run3 Hgg photon preselection

Updating the rho correction of photon isolation For Run3 From Egamma recommendations. For Run3, Quadratic EA corrections are recommended.

Link to Egamma studies : https://indico.cern.ch/event/1204277/contributions/5064356/attachments/2538496/4369369/CutBasedPhotonID_20221031.pdf

Link to the values of EA : https://prrout.web.cern.ch/prrout/Egm_Run3_Effective_Area/EA_rho_corr_photonIso_fromShubham.png

Corrected photon Isolation = photon isolation - (rho x EA1) - (rho x rho x EA2)

The EA1 and EA2 are the linear and quadratic values and are provided for EB and EE separately in Egamma.

NB : The PU correction study was done for both particle (photon isolation) and cluster isolation (ECAL isolation). The cluster isolations perform better than particle isolations in Run3. The linear and quadratic EA values for correcting ECAL isolation is provided in the Run3 from Egamma. Since Hgg uses photon isolation, so the linear and quadratic values for EA are provided here to correct the photon isolation.

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