Absorption and Counting-Efficiency Data for X-Ray Detectors

Abstract

Mass absorption coefficient data published by Allen, Bragg, and Victoreen for the wavelength region 0.1 to 50 A are plotted for several common x-ray tube and counter windows (Al, Be, and mica) and gases (Xe, Kr, A, and Ne) used in x-ray detectors. A graph of the calculated percentage transmission of the windows is presented. The calculated quantum-counting efficiencies for the range 0.1 to 15 A are shown for an end-window argon-filled Geiger counter, side-window Xe, Kr, A, and Ne proportional counters and an NaI·Tl scintillation counter. Some of the factors to be considered in the choice of detectors for x-ray diffractometry and x-ray spectroscopy are discussed particularly with respect to the spectral sensitivity.

Microdetermination of Heavy Elements Such as Mercury and Iodine, in Solution, by X-Ray Absorption

“…An argon-filled Geiger counter, having a quantum-counting efficiency of about 15% for the range of wave lengths discussed here, wTas used as an x-ray de-tector. More accuracy could probably be attained by using a krypton proportional counter having an efficiency of approximately 40% in this wave length range, or a scintillation counter as discussed by Taylor and Parrish (11). Nevertheless, the data obtained for these two examples substantiate the theory well enough to indicate that this technique may be applied to other elements when experimental conditions can be adjusted to satisfy Equation 5.…”

“…The other solutions were ex'aporated at 110°C. Siliconetreated Kirk ultramicropipets (11) were used for pipetting.…”

Monochromatic Diffraction-Absorption Technique for Direct Quantitative X-Ray Analysis

“…Taylor and Parrish (8) compare the proportional counter with the Geiger counter and discuss its advantages. In particular, the xenon proportional counter has about the same counting efficiency at all wave lengths as the Geiger counter and has a linear response to very high counting rates.…”

Solar X-ray observations by Injun 1

“…The 213 Geiger tube (213 GM) in Injun I was intended only for particle measurements, and no experimental X-ray calibrations in the energy range below 30 kev were performed before launch. Hence, following other workers [Taylor and Parrish, 1955;Kreplin, 1961], we estimated the absolute photon effi- VAN of iron is of particular concern.) (b) The mass absorption coefficient of some of the elements in mica are not listed in standard tables for X-ray energies below I key.…”