120289524
Calculation of the intensity of Touschek electrons in the VEPP-4M storage ring
Formulas for calculating the intensity of intrabeam scattering of electrons in the Born approximation for the one- and two-dimensional collision models have been obtained for the nonrelativistic and relativistic cases. The Baier-Katkov-Strakhovenko two-dimensional relativistic model with Coulomb corrections has been analyzed. Formulas in the ultrarelativistic limit have been obtained using this model. Different models have been compared. The intensities of Touschek electrons and the polarization contribution have been calculated under the conditions of the detection of scattered particles at the VEPP-4M storage ring. The calculations have been compared to experimental data.
118623741
PARAMETERS OF CHARMONIUM STATES FROM KEDR
We report results of experiments performed with the KEDR detector at the VEPP-4M e+e- collider. They include final results for the mass and other parameters of the J/ψ, ψ(2S) and ψ(3770) and J/ψ → γηc branching fraction determination.
119195362
Measurement of the ratio of the leptonic widths $\Gamma_{ee}/\Gamma_{\mu\mu}$ for the $J/\psi$ meson
The ratio of the electron and muon widths of the $J/\psi$ meson has been measured using direct $J/\psi$ decays in the KEDR experiment at the VEPP-4M electron-positron collider. The result $\Gamma_{ee}(J/\psi)/\Gamma_{\mu\mu}(J/\psi)=1.0022\pm0.0044\pm0.0048\ (0.65\%)$ is in good agreement with the lepton universality. The experience collected during this analysis will be used for a $J/\psi$ lepton width determination with up to 1% accuracy.
123339284
The KEDR detector
The KEDR detector is a universal magnetic detector designed for studying the c- and b-quarks and two-photon physics, and is employed at the VEPP-4M e + e − collider. A specific feature of the experiment is the measurement of absolute beam energy using two methods: the resonant depolarization and the faster but less precise Compton backscattering of laser photons. This allowed a large series of measurements to be performed, in which the accuracy of determination of such fundamental parameters of particles as mass and total and leptonic widths was improved.
62830427
MEASUREMENT OF THE ENERGY DEPENDENCE OF TOUSCHEK ELECTRON COUNTING RATE
We have measured a dependence of the intra-beam scattering rate on the VEPP-4M beam energy and compared it with our theoretical estimates. Measurements have been performed at several energy points in a wide range: from 1.85 up to 4.0 GeV.
49381889
60 KEV 30 KW ELECTRON BEAM FACILITY FOR ELECTRON BEAM TECHNOLOGY
At the Budker Institute of Nuclear Physics, Novosibirsk, the 60 keV 30 kW electron beam facility for electron beam technology has been developed. The electron gun provides continuous or modulated beam within the current range from 1 mA up to 500 mA. The optical system allows both static and dynamic focusing of the electron beam within the 50÷500 mm range of distance from the gun outlet, the beam scanning and its parallel displacement from the optical axis. The electron gun facility is controlled by the computer via the CAN interface. This paper presents the general description of the facility, its block diagram and main parameters.