Measurements of the HLT performance of displaced muons using Cosmics data ( CMS DP-2019/028)

This note presents the performance of a dedicated displaced standalone muon reconstruction at the High Level Trigger in cosmics data recorded with the CMS detector in 2016. The results are presented as a function of the impact parameter of the offline reconstructed muon. A double muon trigger based on this muon reconstruction has been developed for the search of long-lived particles decaying into dimuons with 2018 data. The trigger relies only on information from the muon detectors to allow sensitivity to decays beyond the inner tracking detector. Details can be found in the public note CMS-DP-2019-028.

Event display of a typical cosmic muon recorded in CMS A cosmic muon is reconstructed as two offline back-to-back dSA muons in CMS. Left: Rho-Phi plane; Right: Rho-Z plane. Contact: Sebastian Templ

Efficiency of the trigger HLT_L2Mu10_NoVertex_CosmicSeed for displaced muons HLT_L2Mu10_NoVertex_CosmicSeed reconstruction efficiency for offline displaced standalone (dSA) muons measured in Cosmics data as a function of the transverse impact parameter d0. Efficiencies are computed w.r.t. events with lower-leg offline dSA muons with pT > 25 GeV selected with a SingleMuOpen L1 trigger. For all results, abs(eta)< 1.2 is applied. [Get pdf version] Contact: Sebastian Templ

Trigger efficiency for HLT_L2Mu23_NoVertex_CosmicSeed Trigger turn-on efficiencies for HLT_L2Mu23_NoVertex_CosmicSeed as a function of the transverse momentum pT of offline displaced standalone (dSA) muons in different bins of the transverse impact parameter d0. Efficiencies are measured w.r.t. events recorded with HLT_L2Mu10_NoVertex_CosmicSeed with a SingleMuOpen seeding at L1 that triggered in the lower detector hemisphere. Measurements with cosmic ray muons (blue) are compared to ones with MC signal samples (orange). For all results, abs(eta) < 1.2 is applied. [Get pdf version] Contact: Sebastian Templ

Trigger efficiency for HLT_L2Mu28_NoVertex_CosmicSeed Trigger turn-on efficiencies for HLT_L2Mu28_NoVertex_CosmicSeed as a function of the transverse momentum pT of offline displaced standalone (dSA) muons in different bins of the transverse impact parameter d0. Efficiencies are measured w.r.t. events recorded with HLT_L2Mu10_NoVertex_CosmicSeed with a SingleMuOpen seeding at L1 that triggered in the lower detector hemisphere. Measurements with cosmic ray muons (blue) are compared to ones with MC signal samples (orange). For all results, abs(eta) < 1.2 is applied. [Get pdf version] Contact: Sebastian Templ

-- ElisabettaGallo - 2019-09-26