A new technique is developed to identify dielectrons (e+e−) with Lorentz boost γL?> 20 that produce one single merged cluster in the electromagnetic calorimeter of the CMS detector. The identification uses two multivariate models: one for the case where both electron tracks are reconstructed, and another where only one of the tracks is reconstructed. The efficiency is determined using proton-proton collision data collected at a center-of-mass energy of 13 TeV. Boosted J=ψ mesons decaying into e+e− pairs are used to estimate the efficiency of the model with two tracks, yielding an overall efficiency of 80%. The Z → μþμ−γ events, where the photon converts into a collimated dielectron, are used for the model with a single track, yielding an efficiency of about 60%. A dedicated energy correction for dielectron candidates is also developed using B± → J=ψK± → e+e−K± data.
Highly boosted dielectron identification in proton-proton collisions at √ s = 13 TeV
Abbrescia, M.;Barbieri, M.;Buonsante, M.;Colaleo, A.;De Palma, M.;Elmetenawee, W.;Louka, M.;Mastrapasqua, V.;My, S.;Nenna, F.;Nuzzo, S.;Pellecchia, A.;Pompili, A.;Radogna, R.;Stamerra, A.;Troiano, D.;Venditti, R.;Zaza, A.;D'Anzi, B.;
2026-01-01
Abstract
A new technique is developed to identify dielectrons (e+e−) with Lorentz boost γL?> 20 that produce one single merged cluster in the electromagnetic calorimeter of the CMS detector. The identification uses two multivariate models: one for the case where both electron tracks are reconstructed, and another where only one of the tracks is reconstructed. The efficiency is determined using proton-proton collision data collected at a center-of-mass energy of 13 TeV. Boosted J=ψ mesons decaying into e+e− pairs are used to estimate the efficiency of the model with two tracks, yielding an overall efficiency of 80%. The Z → μþμ−γ events, where the photon converts into a collimated dielectron, are used for the model with a single track, yielding an efficiency of about 60%. A dedicated energy correction for dielectron candidates is also developed using B± → J=ψK± → e+e−K± data.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


