2008/11/20 by A. Badertscher, Badertscher, A., L. Knecht +13
Engineering · Physics and Astronomy · #FOS: Physical sciences #Instrumentation and Detectors (physics.ins-det) #Particle Accelerators and Free-Electron Lasers #Particle Detector Development and Performance #Photocathodes and Microchannel Plates #physics.ins-det
paper · pdf · doi:10.48550/arxiv.0811.3384
7 pages, 12 figures, Proc. 2008 IEEE Nuclear Science Symposium, Dresden, Germany
arxiv created 2008/11/20 · openalex publication_date 2008/11/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We successfully operated a novel kind of LAr Time Projection Chamber based on a Large Electron Multiplier (LEM) readout system. The prototype, of about 3 liters active volume, is operated in liquid-vapour (double) phase pure Ar. The ionization electrons, after drifting in the LAr volume, are extracted by a set of grids into the gas phase and driven into the holes of a double stage LEM, where charge amplification occurs. Each LEM is a thick macroscopic hole multiplier of 10x10 cm2 manufactured with standard PCB techniques. The electrons signal is readout via two orthogonal coordinates, one using the induced signal on the segmented upper electrode of the LEM itself and the other by collecting the electrons on a segmented anode. Custom-made preamplifiers have been especially developed for this purpose. Cosmic ray tracks have been successfully observed in pure gas at room temperature and in double phase Ar operation. We believe that this proof of principle represents an important milestone in the realization of very large, long drift (cost-effective) LAr detectors for next generation neutrino physics and proton decay experiments, as well as for direct search of Dark Matter with imaging devices.