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arXiv · 1612.05045

The Super-FRS GEM-TPC prototype development - TDR

Abstract

This document contains the pre-design of the beam diagnostics components Tracking Detectors for the Super-FRS. A GEM-TPC detector has been suggested as suitable tracking detector for the ion/fragment beams produced at the in-flight separator Super-FRS under construction at the FAIR facility. The detector concept combines two widely used approaches in gas filled detectors, the Time Projection Chamber (TPC) and the Gas Electron Multiplication (GEM). Three detector generations (prototypes) have been tested in 2011, 2012 and 2014 with relativistic ion beams at GSI. Due to the high-resolution achromatic mode of the Super-FRS, highly homogeneous transmission tracking detectors are crucial to tag the momentum of the ion/fragment beam. They must be able to provide precise information on the (horizontal and vertical) deviation from nominal beam optics, while operated with slow-extracted beam on event-by event basis, in order to provide unambiguous identification of the fragments. The main requirements are a maximum active area horizontally and vertically of (380x80) mm2, a position resolution of < 1 mm, a maximum rate capability of 1 MHz, a dynamic range of about 600 fC. About 32 tracking detectors operating in vacuum are needed along the Super-FRS beam line.

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F. Garcia, C. Caesar, T. Grahn, A. Prochazka, B. Voss. 2016-12-15. The Super-FRS GEM-TPC prototype development - TDR. https://arxiv.org/abs/1612.05045

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