分类: 物理学 >> 核物理学 提交时间: 2016-09-13
摘要: We study the photon detection efficiency and position resolution of the electromagnetic calorimeter (EMC) of the BESIII experiment. The control sample of the initial-state-radiation (ISR) process of e+e−→γμ+μ− is used at J/ψ and ψ(3770) resonances for the EMC calibration and photon detection efficiency study. Photon detection efficiency is defined as the predicted photon, obtained by performing a kinematic fit with two muon tracks, matched with real photons in the EMC. The spatial resolution of the EMC is defined as the separation in polar (θ) and azimuthal (ϕ) angles between charged track and associated cluster centroid on the front face of the EMC crystals.
分类: 物理学 >> 核物理学 提交时间: 2016-09-06
摘要: We study the photon detection efficiency and position resolution of the electromagnetic calorimeter (EMC) of the BESIII detector. The control samples of the initial-state-radiation (ISR) process of e+e−→γμ+μ− at J/ψ and ψ(3770) resonances are used for the calibration of the photon cluster shapes and photon detection efficiency study. The photon detection efficiency is defined as the fraction of predicted photon, determined by performing a kinematic fit with the four momenta of two charged tracks only, matched with the actual photons in the EMC. The spatial resolution of the EMC is studied in polar (θ) and azimuthal (ϕ) angle directions in a cylindrical coordinate system centered at the interaction point, with z-axis along the beam direction.