Speaker
Dr
展翔 高
(南京大学)
Description
In the H→Zγ search, the main backgrounds are Z+jets, with jets misidentified as photons, and Z+γ, which shares the same final state as the signal. The Z+jets background is estimated using an ABCD method based on photon isolation and ID, with fake factors derived as a function of photon $P_T$
. For the Z+γ background, far-sideband samples ($M_{ll\gamma}$<100GeV, $M_{ll\gamma}$>160GeV) are used to train a BDT and extract scale factors, which are then applied to simulation. Signal extraction is performed with the reconstructed Higgs mass $M_{ll\gamma}$,This data-driven strategy achieves ~15% accuracy in sidebands and avoids relying on high order empirical functions for background modeling.
