A driftless gas proportional scintillation counter for muonic hydrogen X-ray spectroscopy under strong magnetic fields

An experiment involving muonic hydrogen requires an X-ray detector having l arge area and working under strong magnetic fields (5 T) with good energy a nd timing resolution. A compact, driftless gas proportional scintillation c ounter (GPSC capable of operating under such magnetic fields is investigate d. This GPSC uses a CsI photocathode deposited onto a microstrip plate as t he UV scintillation readout photosensor. This photocathode has the advantag e of operating in direct contact with the scintillation gas. The detector i s filled with pure xenon and is designed to have a high detection efficienc y for 2 keV X-rays. Energy resolutions of 23 % and 22% were obtained for 1. 74 and 2.3 keV X-rays, respectively. The low-energy detector limit due to t he electronic noise is 300 eV. Its performance in the presence of strong ma gnetic fields was tested. At magnetic field of 5 T the detector pulse ampli tudes are reduced by less than 25%, while the detector energy resolution an d pulse rise time present a relative increase of less than 10%. (C) 2001 El sevier Science B.V. All rights reserved.