Trigger efficiencies at BES III

TL;DR

This paper reports on the measurement of trigger efficiencies at BES III for various physics events, demonstrating efficiencies above 99%, which meet the experiment's design goals.

Contribution

First comprehensive measurement of trigger efficiencies at BES III across multiple event types, confirming system performance aligns with design specifications.

Findings

Trigger efficiencies exceed 99% for all studied events

Efficiencies meet BES III design specifications

Data from dedicated runs and physics datasets were used

Abstract

Trigger efficiencies at BES III were determined for both the J/psi and psi' data taking of 2009. Both dedicated runs and physics datasets are used; efficiencies are presented for Bhabha-scattering events, generic hadronic decay events involving charged tracks, dimuon events and psi' -> pi+pi-J/psi, J/psi -> l+l- events (l an electron or muon). The efficiencies are found to lie well above 99% for all relevant physics cases, thus fulfilling the BES III design specifications.