TY - JOUR
T1 - X-ray position resolution in proportional chambers in the region of 100 μm (FWHM) above the xenon K-edge
AU - Smith, G. C.
AU - Cox, D. E.
AU - Jephcoat, A. P.
N1 - Funding Information:
Position-sensitive proportional chambers have important applications in many areas of science. At Brookhaven we have been developing these devices for X-ray scattering and diffraction studies for several years. It is very helpful in these applications to understand the fundamental limitation to position resolution due to specific characteristics of the detector. Photoelectron and Auger electron range, electron diffusion, anode avalanche spreading, electronic noise of the position encoder and parallax are several factors which can contribute to the position accuracy . We have already determined experimentally the limitation to position resolution in argon, krypton and xenon, due to the range in the detector gas of the photoelectron and Auger electron emitted from the target atom, for X-rays in the energy range 5 to 25 keV [1,2]; these studies showed the importance of low anode charge and optimized position readout, and yielded the smallest X-ray position resolution measured so far in a gas proportional detector of 14 p,m (FWHM) for 8 keV photons in a Xe/10%CO 2 mixture at 10 bar. Similar, very accurate measurements at photon energies above 25 keV have not yet been carried out. For X-rays with energy just above the xenon K-edge of 34 .6 keV, advantage may be taken of the low energy (and short range) photoelectron created, using the technique of escape peak gating that has already demonstrated excellent position resolution in krypton for photon energies just above This research was supported by the US Department of Energy : Contract No . DE-AC02-76CH00016, and by NATO CRG 890994 . * Corresponding author. Tel. + 1 516 282 4253, gsmith@bnluxl .bnl .gov .
PY - 1994/11/1
Y1 - 1994/11/1
N2 - A brief discussion is presented of the X-ray absorption process in xenon above its K-edge of 34.6 keV. Experimental measurements from a one-dimensional proportional chamber, operating with a gas mixture of Xe/10%CO2, show that position resolution in the region of 100 μm FWHM can be achieved for X-rays with energy just above the K-edge.
AB - A brief discussion is presented of the X-ray absorption process in xenon above its K-edge of 34.6 keV. Experimental measurements from a one-dimensional proportional chamber, operating with a gas mixture of Xe/10%CO2, show that position resolution in the region of 100 μm FWHM can be achieved for X-rays with energy just above the K-edge.
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U2 - 10.1016/0168-9002(94)91267-X
DO - 10.1016/0168-9002(94)91267-X
M3 - Letter
AN - SCOPUS:0028546236
SN - 0168-9002
VL - 350
SP - 621
EP - 623
JO - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
JF - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
IS - 3
ER -