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Performance of the AMS-02 Transition Radiation Detector

P. v. Doetinchem·S. Fopp·W. Karpinski·T. Kirn·K. Luebelsmeyer·J. Orboeck·S. Schael·A. Schultz von Dratzig·G. Schwering·T. Siedenburg·R. Siedling·W. Wallraff·U. Becker·J. Burger·R. Henning·A. Kounine·V. Koutsenko·J. Wyatt
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Abstract

For cosmic particle spectroscopy on the International Space Station the AMS experiment will be equipped with a Transition Radiation Detector (TRD) to improve particle identification. The TRD has 20 layers of fleece radiator with Xe/CO2 proportional mode straw tube chambers. They are supported in a conically shaped octagon structure made of CFC-Al-honeycomb. For low power consumption VA analog multiplexers are used as front-end readout. A 20 layer prototype built from final design components has achieved proton rejections from 100 to 2000 at 90% electron efficiency for proton beam energies up to 250 GeV with cluster counting, likelihood and neural net selection algorithms.

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P. v. Doetinchem, S. Fopp, W. Karpinski, T. Kirn, K. Luebelsmeyer, J. Orboeck, S. Schael, A. Schultz von Dratzig, G. Schwering, T. Siedenburg, R. Siedling, W. Wallraff, U. Becker, J. Burger, R. Henning, A. Kounine, V. Koutsenko, J. Wyatt. 2006-08-29. Performance of the AMS-02 Transition Radiation Detector. https://doi.org/10.1016/j.nima.2005.12.187

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