Bonn 2010 – wissenschaftliches Programm
HK 36.74: Poster
Mittwoch, 17. März 2010, 14:00–16:00, HG Aula
Development of a thin beam counter with high quantum efficiency photomultipliers for the COMPASS experiment — •Christoph Adolph1, Jens Bisplinghoff2, Wolfgang Eyrich1, Christopher Braun1, and Rainer Joosten2 — 1Physikalisches Institut IV der Universität Erlangen-Nürnberg — 2Helmholtz Institut für Strahlen- und Kernphysik Universität Bonn
The beam counting at the COMPASS experiment is done up to now by a small scintillating plate with a single photomultiplier readout three meters in front of the target. To improve the information, especially the spatial resolution, a beam counter built of scintillating fibers with an active size of 4.2×4.2cm2 was developed. Each of the two layers of the two planes consists of 64 fibers with a length of 14cm and a diameter of 1mm leading to a thickness of only 2.5mm per plane. This allows the use of this new beam counter not only for myon beam but also for hadron beam. To increase the number of detected photons, which is essential for such thin scintillator planes, new Hamamatsu super-cathode 16 channel multi-anode photomultiplier (MaPMT) type H6568-100 with increased cathode quantum efficiency will be used. Results from first studies of the beam counter during the 2009 myon run period and the characteristics of the H6568-100 MaPMT will be shown.
supported by German BMBF