A high position resolution X-ray detector: an "Edge on" illuminated capillary plate combined with a gas amplification structure

Abstract

Abstract-We have developed and successfully tested a prototype of a new high position resolution hybrid X-ray detector. It contains a thin-wall lead glass capillary plate converter of X-rays combined with a microgap parallel-plate avalanche chamber operating in various gas mixtures at 1 atm.The operation of these converters was studied in a wide range of X-ray energies (from 6 to 60 keV) at incident angles varying from 0-90 . The detection efficiency, depending on the geometry, photon's energy, incident angle and the mode of operation was between 5-30% in single step mode and up to 50% in a multi-layered combination. Depending on the capillary's geometry, the position resolution achieved was between 50-250 m in digital form and was practically independent of the photon's energy or gas mixture. The usual lead glass capillary plates operated without noticeable charging up effects at counting rates of 50 Hz/mm 2 and hydrogen treated capillaries-up to 10 5 Hz/mm 2 . The developed detector has several important potential advantages over the exciting X-ray detectors and may open new possibilities for medical imaging, for example in mammography, portal imaging, radiography (including security devices), as well as many other applications.

Position-Sensitive Gaseous Photomultipliers

“…In this case solid photocathodes were used as efficient converters. One of the latest developments is a high position resolution X-ray scanner for radiography [51].…”

The radiation gas detectors with novel nanoporous converter for medical imaging applications

“…But these detectors have usually poor energy resolution and also low detection affciency for energetic Xrays. The radiation gaseous detectors are currently employed in digital X-ray radiography [1], angiography [2], mammography [3,4] and high-pressure ones for Computerized Tomography (CT) [5]. For more energitic gamma rays, for example in a Positron Emission Tomography (PET) imaging system [6], usually a solid converter such as thick metal-grid converter is coupled to a position-sensitive gas avalanche detectors, [7].…”

Characterisation of NEXT-DEMO using xenon KαX-rays

“…Gas detector and, particularly, time projection chamber (TPC) technology have been developed over a number of years and now find applications in a diverse range of fields. The relative ease with which noble gases can be cleaned of impurities as well as the availability of both scintillation and ionization signals when using these materials as target has meant that such detectors have been extensively used in medical imaging, dark matter detection, X-ray astronomy, and for the observation of double beta decay (see for example [1][2][3][4]). Xenon, both as a gas and liquid, is of special interest for applications in which the energy of the interacting particle must be measured.…”