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arXiv · 0909.3544

Making spherical GEMs

Serge Duarte Pinto·Marco Villa·Matteo Alfonsi·Ian Brock·Gabriele Croci·Eric David·Rui de Oliveira·Leszek Ropelewski·Miranda van Stenis·Hans Taureg
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Abstract

We developed a method to make GEM foils with a spherical geometry. Tests of this procedure and with the resulting spherical GEMs are presented. Together with a spherical drift electrode, a spherical conversion gap for x-rays can be formed. This would eliminate the parallax error in an x-ray diffraction setup, which limits the spatial resolution at wide diffraction angles. The method is inexpensive and flexible towards possible changes in the design. We show advanced plans to make a prototype of an entirely spherical triple-GEM detector, including a spherical readout structure. This detector will have a superior position resolution, also at wide diffraction angles, and a high rate capability. A completely spherical gaseous detector has never been made before.

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Serge Duarte Pinto, Marco Villa, Matteo Alfonsi, Ian Brock, Gabriele Croci, Eric David, Rui de Oliveira, Leszek Ropelewski, Miranda van Stenis, Hans Taureg. 2009-09-18. Making spherical GEMs. https://doi.org/10.1088/1748-0221/4/12/p12006

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