BESⅡ上光子探测效率的研究

Study of Photon Detection Efficiency at BESⅡ

利用J/ ψ→ρπ衰变道 ,对BESⅡ上BSC对于光子的探测效率做了细致的研究 .结果表明在从探测器光子能量阈值直到BES上可产生的最大光子能量范围内 ,用目前的MonteCarlo可以在1%— 3%的精度下模拟光子的探测效率 .并且对MonteCarlo在探测效率上与数据的差别进行了详细研究 .同时用质心系能量s =3.770GeV处的e+e- →γe+e- 数据检验了高能区MonteCarlo和数据的探测效率都达到 10 0 % ,并且在

The photon detection efficiencies of Monte Carlo simulation and data are studied using three methods in the decay of J/ψ→ρπ at BESⅡ.The results show that the Monte Carlo can simulate the photon detection efficiency of data in the precision of 1%-3%.The source of discrepancy between Monte Carlo and data is also studied in this work.The sample of e +e -→γe +e - at the center of mass energy of s =3.770GeV is used to study the detection efficiencies of the photons with the energies greater than 1.4 GeV for Monte Carlo and data that are both 100%,and the difference of the photon detection efficiency between Monte Carlo and data is less than 1%.