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arXiv · hep-ex/9610005

Separation of γ/π^0 showers at high energies

J. Grunhaus·S. Kananov
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Abstract

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 π^0 showers from γshowers in the 30 to 150 GeV energy range. For 90% γacceptance the SMD-dos yields π^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 π^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-->γγ. The addition of a SMD-dos to the planned detectors at the LHC would significantly reduce the background to the γ-signal coming from prolific π^0 production.

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J. Grunhaus, S. Kananov. 1996-10-14. Separation of γ/π^0 showers at high energies. https://doi.org/10.1016/s0168-9002(97)00520-2

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