Performance of a MICROMEGAS-based TPC in a high-energy neutron beam

Lucas Snyder; Brett Manning; Nathaniel S. Bowden; Jeremy Bundgaard; Robert J. Casperson; Daniel A. Cebra; Timothy Classen; Dana L. Duke; Joshua Gearhart; Uwe Greife; Christian Hagmann; Michael Heffner; David Hensle; Daniel Higgins; Donald Isenhower; Jonathan King; Jennifer L. Klay; Verena Geppert-Kleinrath; Walter Loveland; Joshua A. Magee; Michael P. Mendenhall; Samuele Sangiorgio; Brandon Seilhan; Kyle T. Schmitt; Fredrik Tovesson; Rusty S. Towell; Nicholas Walsh; Shon Watson; Liangyu Yao; Walid Younes

doi:10.1016/j.nima.2017.10.028

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arXiv · 1712.01830

Performance of a MICROMEGAS-based TPC in a high-energy neutron beam

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Abstract

The MICROMEGAS (MICRO-MEsh GAseous Structure) charge amplification structure has found wide use in many detection applications, especially as a gain stage for the charge readout of Time Projection Chambers (TPCs). Here we report on the behavior of a MICROMEGAS TPC when operated in a high-energy (up to 800 MeV) neutron beam. It is found that neutron-induced reactions can cause discharges in some drift gas mixtures that are stable in the absence of the neutron beam. The discharges result from recoil ions close to the MICROMEGAS that deposit high specific ionization density and have a limited diffusion time. For a binary drift gas, increasing the percentage of the molecular component (quench gas) relative to the noble component and operating at lower pressures generally improves stability.

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Lucas Snyder, Brett Manning, Nathaniel S. Bowden, Jeremy Bundgaard, Robert J. Casperson, Daniel A. Cebra, Timothy Classen, Dana L. Duke, Joshua Gearhart, Uwe Greife, Christian Hagmann, Michael Heffner, David Hensle, Daniel Higgins, Donald Isenhower, Jonathan King, Jennifer L. Klay, Verena Geppert-Kleinrath, Walter Loveland, Joshua A. Magee, Michael P. Mendenhall, Samuele Sangiorgio, Brandon Seilhan, Kyle T. Schmitt, Fredrik Tovesson, Rusty S. Towell, Nicholas Walsh, Shon Watson, Liangyu Yao, Walid Younes. 2017-12-04. Performance of a MICROMEGAS-based TPC in a high-energy neutron beam. https://doi.org/10.1016/j.nima.2017.10.028

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