标题： 高能γ/π⁰簇射的分离 显示英文标题

标题： Separation of γ/π^0 showers at high energies

摘要： 我们设计并进行了模拟研究，针对30到150 GeV能量范围内区分 \$\pi ^0\$ 洗脱和\gamma 洗脱的二层斜置（SMD-dos）淋洗最大检测器进行了优化。对于90%的\gamma 接受度，当入射能量分别为30 GeV、50 GeV和150 GeV时，SMD-dos分别达到了92±4%、87±4%和32±2%的 \$\pi ^0\$ 排斥效率。我们发现，与同等分辨率的传统几何结构单层或多层淋洗最大检测器（SMD）相比，在50到150 GeV的能量范围内，SMD-dos的性能平均高出约1.5倍。同时，我们还发现，与SMD相比，SMD-dos在相同通道数的情况下具有更好的 \$\pi ^0\$ 排斥能力。在强子-强子对撞机上，探测质量范围为120到160 GeV的希格斯粒子的最佳信号是通过衰变 \$H \to\gamma \gamma \$ 来实现的。 在LHC计划中的探测器中加入SMD-dos，将显著减少来自丰富的\pi 0生产的\gamma 信号的背景。 显示英文摘要

摘要： We have designed and carried out simulation studies of a two layer Shower Maximum Detector diagonally off-set (SMD-dos) optimized for the separation of \pi^0 showers from \gamma showers in the 30 to 150 GeV energy range. For 90% \gamma acceptance the SMD-dos yields \pi^0 rejection efficiency of 92+-4%, 87+-4% and 32+-2%, respectively, for 30, 50 and 150 GeV incident energies. We find that the SMD-dos is superior to a conventional geometry single-layer or mutiple-layer shower maximum detector (SMD), of equal granularity, by an average factor of ~1.5 over the 50 to 150 GeV energy range. We also find that the SMD-dos gives better \pi^0 rejection, for the same number of channels, than a SMD. At hadron - hadron colliders the signature of choice for the detection of the Higgs particle, in the mass range of 120 to 160 GeV, is via the decay H-->\gamma\gamma. The addition of a SMD-dos to the planned detectors at the LHC would significantly reduce the background to the \gamma-signal coming from prolific \pi^0 production.