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arXiv · 0707.3257

Investigations of a THGEM-based imaging detector

M. Cortesi·R. Alon·R. Chechik·A. Breskin·D. Vartsky·V. Dangendorf
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Abstract

We present the results of our recent studies on a Thick Gas Electron Multiplier (THGEM)-based imaging detector prototype. It consists of two 100x100 mm^2 THGEM electrodes in cascade, coupled to a resistive anode. The event location is recorded with a 2D double-sided readout electrode equipped with discrete delay-lines and dedicated electronics. The THGEM electrodes, produced by standard printed-circuit board and mechanical drilling techniques, a 0.4 mm thick with 0.5 mm diameter holes spaced by 1 mm. Localization resolutions of about 0.7 mm (FWHM) were measured with soft x-rays, in a detector operated with atmospheric-pressure Ar/CH4; good linearity and homogeneity were achieved. We describe the imaging-detector layout, the resistive-anode 2D readout system and the imaging properties. The THGEM has numerous potential applications that require large-area imaging detectors, with high-rate capability, single-electron sensitivity and moderate (sub-mm) localization resolution.

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M. Cortesi, R. Alon, R. Chechik, A. Breskin, D. Vartsky, V. Dangendorf. 2007-12-26. Investigations of a THGEM-based imaging detector. https://doi.org/10.1088/1748-0221/2/09/p09002

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