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The performance characteristics of the Off Specular MicrOstrip Neutron Detector (OSMOND) are described. Based on microstrip gas chamber (MSGC) detectors, OSMOND is a high counting rate detector, with sub-millimeter position resolution, capable of replacing the existing rate limited scintillator detectors currently in use on the suite of reflectometer instruments of the ISIS spallation neutron source. The detector system is described together with results of neutron beam tests carried out on the CRISP and POLREF reflectometers. [ABSTRACT FROM PUBLISHER]

The development and testing of the SuPerior Rate for INTER (SPRINTER) detector is described. Based on a microstrip gas chamber (MSGC), the aim of the project was to produce a matched pair of high-counting-rate detectors capable of replacing the existing ^3He tubes currently used on the INTER reflectometer of the ISIS spallation neutron source. The detector system is described, and the results from the first neutron beam tests carried out on an ISIS neutron reflectometer are also shown. [ABSTRACT FROM PUBLISHER]

Over the past 10 years combined techniques such as small angle and wide angle X-ray scattering (SAXS/WAXS) and X-ray absorption spectroscopy (XAS) with X-ray diffraction (XRD), have become the mainstay of time resolved experimental studies carried out at synchrotron radiation sources (SRS). However, these techniques have been limited by the detectors used to measure the wide angle scattering/diffraction pattern, and therefore restrict the dynamic experiments that can be studied. The HOTWAXS (High Overall Throughput Wide-Angle X-ray Scattering) detector project was designed to address this issue by producing a position sensitive, parallax free, high count rate, photon counting detector based on microstrip gas chamber (MSGC) technology. The initial experiments, performed on station 16.1 of the Daresbury SRS, with a high density polyethylene sample, confirmed the local count rate per channel to be 1 × 106 counts per second. A global count rate over the 512 channel detector of 27 × 106 counts per second was also measured for this sample. Time resolved experiments on stations 2.1 and 9.3 with real 'user' samples have also been performed, the results of which are presented. [ABSTRACT FROM AUTHOR]

The development and testing of a two-dimensional (2-D) prototype detector based on a microstrip gas chamber (MSGC) is reported using a gas mixture of 2.5 bar ³He and 2.5 bar CF4. The second coordinate is obtained by utilising a plane of wires as pick up electrodes. The detector is operated with the wire plane at such a potential so as not to induce any gain around the wires. This means that the high tolerances normally associated with wire planes in multi wire proportional counters are not mandatory. The detector comprises of 48 individually instrumented channels in both X (MSGC strips) and Y (orthogonal wire plane). A specially designed encoding module has been constructed which feeds digital addresses for each event to the ISIS Data Acquisition Electronics (DAE) system. An intrinsic detector resolution of ∼1 mm full-width at half-maximum has been measured for both dimensions (in experimental exposures on the ROTAX beamline at ISIS) which is degraded slightly by the digital resolution for the overall system. This readout method is shown to be very tolerant of a poor signal to noise ratio in the readout channels (unlike traditional analogue wire chamber readout systems) and permits the operation of the MSGC at low avalanche gains (∼10) which helps to maximize the rate and lifetime performance of the detector as well as permitting data capture rates in the megahertz range. The event timing resolution is comfortably submicrosecond and is, therefore, suitable for applications on spallation neutron sources. [ABSTRACT FROM AUTHOR]

The development and testing of a two-dimensional (2-D) prototype detector based on a microstrip gas chamber (MSGC) are reported. The second coordinate is obtained by utilising a plane of wires as pick up electrodes. The detector is operated with the wire plane at such a potential so as not to induce any gain around the wires. This means that the high tolerances normally associated with wire planes in multiwire proportional counters are not necessary, making the manufacture and repair of such a device relatively easier. The detector comprises of 48 individually instrumented channels in both X (MSGC strips) and Y (transverse wire plane). A specially designed encoding module has been constructed which feeds digital addresses for each event to the ISIS data acquisiton electronics (DAE) system. (ISIS is the spaliation neutron source at the Rutherford Appleton Laboratory.) An intrinsic detector resolution of ∼ 0.5 mm full-width at half-maximum (FWHM) has been measured for both dimensions which is degraded slightly by the digital resolution for the overall system. This readout method is shown to be very tolerant of a poor signal-to-noise ratio in the readout channels (unlike traditional analogue wire chamber readout systems) and permits the operation of the MSGC at moderate avalanche gains (∼ 1000) which helps to maximize the rate and lifetime performance of the detector as well as permitting data capture rates in the MHz range. [ABSTRACT FROM AUTHOR]

Presents a study which investigated the dependence of the gas gain and pulse-height resolution of the plate as a function of various geometric and gas parameters. Capabilities of the microstrip gas counter (MSGC); Basic gain parameters of an MSGC; Gain dependence on strip geometry; Gain dependence on the drift gap width.