Toward the Energy Resolution Limit of Mercuric Iodide in Room Temperature Low Energy X-Ray Spectrometry

We have previously reported on the uniqueness and potential of room-temperature spectrometry of low-energy x-rays with a mercuric iodide (HgI2) detector (1,2,3). In this paper we emphasize the use of HgI2 detectors for x-ray fluorescence (XRF) analysis.Because no vacuum plumbing or cryogenic cooling is required, the design of a mercuric iodide room-temperature x-ray spectrometer is extremely simple. Our present design consists of coupling a detector directly to the first-stage FET in a modified Tennelec 161 D preamplifier and making the configuration “light-tight”. Aside from providing a suitable entrance window, there are no other requirements for routine spectroscopy.

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Continuing Development of Mercuric Iodide X-Ray Spectrometry

Advances in X-ray Analysis ◽

10.1154/s0376030800017328 ◽

1983 ◽

Vol 27 ◽

pp. 405-414 ◽

Cited By ~ 1

Author(s):

J.S. Iwanczyk ◽

A.J. Dabrowski ◽

G.C. Huth ◽

W. Drummond

Keyword(s):

Energy Resolution ◽

Noise Level ◽

Room Temperature ◽

Optical Feedback ◽

The Other ◽

Spectral Energy ◽

Electronic Noise ◽

Mercuric Iodide ◽

X Ray ◽

Resolution Capability

The continuing development in recent years of mercuric iodide room temperature x-ray spectrometers has led to steady improvment in the spectral energy resolution capability of these systems. This has been due largely to the continuing reduction in the electronic noise level of the associated preamplification electronics. It has been demonstrated that a system consisting of a mercuric iodide detector in combination with a pulsed-optical feedback preamplifier provides superior energy resolution performance in x-ray spectrometry in comparison to the other types of preamplification. Previously, results have been reported by us of the energy resolution of such systems with both the detector and input FET of the preamplifier at room temperature and with the input FET cooled by liquid nitrogen and the mercuric iodide x-ray detectors lightly cooled.

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X-Ray Fluorescence Analysis of High Z Materials with Mercuric Iodide Room Temperature Detectors

Advances in X-ray Analysis ◽

10.1154/s0376030800007485 ◽

1980 ◽

Vol 24 ◽

pp. 303-309 ◽

Cited By ~ 3

Author(s):

J. Nissenbaum ◽

A. Holzer ◽

M. Roth ◽

M. Schieber

Keyword(s):

Solid State ◽

Energy Resolution ◽

Room Temperature ◽

Fluorescence Analysis ◽

Industrial Applications ◽

Mercuric Iodide ◽

Portable Xrf ◽

X Ray ◽

State Radiation ◽

Wide Range

AbstractMercuric iodide HgI2 room temperature solid state radiation spectrometers having 4% energy resolution at 100 KeV detected the x-ray fluorescence (XRF) of the K shell of intermediate and high Z elements. The excitation of the K shells which emit XRF more energetic than 60 KeV was achieved with 7mCi collimated 57Co and for XRF less energetic than 60 KeV the excitation was done with a 10mCi 241Am source. The K shell XRF spectra of a 1:1 mixture of U and Th, and also of the single elements of Au, Tb, Ba, Ag, Mo, and Rb are shown. The results prove the feasibility of developing mercuric iodide portable XRF spectrometers which operate at room temperature and which have a wide range of geochemical and industrial applications.

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Energy Resolution Measurements of Mercuric Iodide Detectors Using a Cooled Fet Preamplifier

Advances in X-ray Analysis ◽

10.1154/s0376030800012647 ◽

1982 ◽

Vol 26 ◽

pp. 325-330 ◽

Cited By ~ 5

Author(s):

Lawrence Ames ◽

William Drummond ◽

Jan Iwanczyk ◽

Andrzej Dabrowski

Keyword(s):

Time Constant ◽

Energy Resolution ◽

Room Temperature ◽

Fano Factor ◽

Low Noise ◽

Mercuric Iodide ◽

X Ray

AbstractThe performance of a room temperature mercuric iodide X-ray detector was investigated as a function of detector bias, amplifier time constant, and detector temperature. A Mn Kα line of 200 eV FWHM was obtained by using low noise electronics developed for Si(Li) detectors, including a cooled input PET. Measurements of the detector's resolution at various X-ray energies result in a Fano factor of 0.20.

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Background and Sensitivity Considerations of X-Ray Fluorescence Analysis with a Room-Temperature Mercuric Iodide Spectrometer

Advances in X-ray Analysis ◽

10.1154/s0376030800007540 ◽

1980 ◽

Vol 24 ◽

pp. 337-343

Author(s):

M. Singh ◽

B.C. Clark ◽

A.J. Dabrowski ◽

J.S. Iwanczyk ◽

D.E. Leyden ◽

...

Keyword(s):

Energy Resolution ◽

Proportional Counter ◽

Room Temperature ◽

Fluorescence Analysis ◽

Considerable Improvement ◽

Mercuric Iodide ◽

X Ray ◽

Water Pollutants ◽

Xrf Analysis ◽

Basic Properties

Continued development of mercuric iodide (HgI2) detectors for x-ray spectroscopy at room-temperature has led to a considerable improvement in energy resolution and a better understanding of the various detector parameters which affect sensitivity. The basic properties of a mercuric iodide detector and some of its characteristics pertinent to x-ray fluorescence analysis have been previously reported (1,2,3). In this paper we present results of studies to determine the shape o£ peaks and continuum background. Also, the use of Hgl2 in characterizing water pollutants by XRF analysis has been investigated and compared to cryogenically cooled Si(Li) and room-temperature proportional counter systems.

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The Fabrication of Mercuric Iodide Detectors for Use in Wavelength Dispersive X-Ray Analysers and Backscatter Photon Measurements

MRS Proceedings ◽

10.1557/proc-16-207 ◽

1982 ◽

Vol 16 ◽

Cited By ~ 10

Author(s):

John H. Howes ◽

John Watling

Keyword(s):

Room Temperature ◽

Gamma Ray ◽

Surface Passivation ◽

Electrical Contact ◽

Scintillation Counter ◽

Radiation Detectors ◽

Nuclear Radiation ◽

Gamma Ray Spectrometry ◽

Mercuric Iodide ◽

X Ray

ABSTRACTThis paper describes the fabrication of mercuric iodide nuclear radiation detectors suitable for X and gamma ray spectrometry at room temperature. The active area of the detectors studied are between 0.2 and 1.5cm sq and they are up to 0.5mm thick. The method of producing a stable electrical contact to the crystal using sputtered germanium has been studied. The X-ray resolution of a 1.5cm sq. area detector at 32 keV is 2.3 keV FWHM when operated at room temperature in conjunction with a time variant filter amplifier. A factor which is important in the fabrication of the detector is the surface passivation necessary to achieve a useful detector life.This type of detector has been used on a wavelength dispersive X-ray spectrometer for energy measurements between 10 and 100 keV. The advantages over the scintillation counter, more commonly used, is the improved resolution of the HgI2 detector and its smaller size. The analyser is primarily used for the detection of low levels of heavy metals on particulate filters. The detectors have also been used on an experimental basis for gamma ray backscatter measurements in the medical field.

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The Gas Proportional Scintillation Counter as a Room-Temperature Detector For Energy-Dispersive X-Ray Fluorescence Analysis

Advances in X-ray Analysis ◽

10.1154/s0376030800009496 ◽

1981 ◽

Vol 25 ◽

pp. 39-44 ◽

Cited By ~ 1

Author(s):

C. A. N. Conde ◽

L. F. Requicha Ferreira ◽

A. J. de Campos

Keyword(s):

Room Temperature ◽

Scintillation Counter ◽

Fluorescence Analysis ◽

Energy Dispersive ◽

X Rays ◽

Mercuric Iodide ◽

X Ray ◽

Temperature Detector ◽

Portable Instruments ◽

Physical Principles

AbstractA review of the basic physical principles of the gas proportional scintillation counter is presented. Its performance is discussed and compared with that of other room-temperature detectors in regard to applications to portable instruments for energy-dispersive X-ray fluorescence analysis. It is concluded that the gas proportional scintillation counter is definitely superior to all other room-temperature detectors, except the mercuric iodide (HgI2) detector. For large areas or soft X-rays it is also superior to the HgI2 detector.

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Suppression of X-Ray Fluorescence Background in X-Ray Powder Diffraction by a Mercuric Iodide Spectrometer

Advances in X-ray Analysis ◽

10.1154/s0376030800017213 ◽

1983 ◽

Vol 27 ◽

pp. 307-316

Author(s):

J. Nissenbaum ◽

A. Levi ◽

A. Burger ◽

M. Schieber ◽

Z. Burshtein

Keyword(s):

Powder Diffraction ◽

Energy Resolution ◽

Scintillation Counter ◽

Peak Height ◽

Maximum Energy ◽

Mercuric Iodide ◽

X Ray Diffraction ◽

X Ray ◽

Order Of Magnitude ◽

Diffraction Patterns

AbstractWe have explored the merits of using a Hgl2 spectrometer as a detector in x-ray diffraction systems instead of a proportional gas counter, or a scintillation counter. The full width at half maximum energy resolution of the HgI2 spectrometer used was about 1.1 keV for the CuKα line (8.1 keV), and about 1.5 keV for the MoKα line (17.4 keV), The energy resolution was utilised to eliminate x-ray fluorescence background from powder diffraction spectra. We demonstrate the suppression of Fe x-ray fluorescence in diffraction patterns of ErFe03 obtained with a Cu x-ray tube, and of Y x-ray fluorescence in diffraction patterns of Y2O3 obtained with a Mo x-ray tube. The peak height to background ratios were improved by about an order of magnitude in both cases.

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