Bridgman Growth of SrI2

ABSTRACTEu2+– activated strontium iodide is a promising material for x-ray and gamma ray detector. A lot of difficulties are though encountered growing strontium iodide crystals due to the high oxygen-sensitivity, hygroscopic property and high impurity concentration. Single crystals of SrI2:Eu were grown from zone refined starting materials in silica ampoules. The crystals showed good optical qualities. The light yield of two samples cut from the same ingot was determined to be 53 000 photons/MeV and 119±22 photons/keV for a 0.4 cm3 sample and a 360 μm sample respectively, indicating some level of light trapping in the bulk sample.

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Wide Band X-Ray Imager (WXI) And Soft Gamma-Ray Detector (SGD) for the NeXT Mission

10.2172/839862 ◽

2005 ◽

Cited By ~ 1

Author(s):

T Takahashi

Keyword(s):

Gamma Ray ◽

Wide Band ◽

X Ray ◽

Gamma Ray Detector

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Defects in Silver-Doped Mercuric Iodide Crystals and their Effect on X-Ray and Gamma-Ray Detector Performance

MRS Proceedings ◽

10.1557/proc-302-103 ◽

1993 ◽

Vol 302 ◽

Cited By ~ 1

Author(s):

R. B. James ◽

X. J. Bao ◽

T. E. Schlesinger ◽

A. Y. Cheng ◽

V. M. Gerrish

Keyword(s):

Gamma Ray ◽

Electrical Contacts ◽

Source Material ◽

Broad Emission Band ◽

Interfacial Region ◽

Mercuric Iodide ◽

Detector Performance ◽

X Ray ◽

Silver Silver ◽

Gamma Ray Detector

ABSTRACTThe processing steps associated with purification of source material, crystal growth, and attachment of electrical contacts can introduce defects into mercuric iodide (HgI2) that degrade the performance of detectors. We have employed low-temperature photoluminescence (PL) spectroscopy to study radiative recombination centers in the interfacial region between a thin semitransparent film of silver and mercuric iodide. The Ag film was found to introduce a new broad emission band centered at 5490 Å in the photoluminescence spectrum of HgI2. This PL feature can be used as a signature to identify the existence of Ag as a contaminant in HgI2 crystals and detectors. Experiments were also conducted on mercuric iodide surfaces that had been doped with silver, and the results showed that Ag is a rapid diffuser in bulk HgI2. Detectors with silver electrodes were also fabricated and tested using an americium-241 gamma-ray source. Large increases in the leakage currents were observed for the Ag-doped HgI2 devices, indicated that Ag impurities are electrically active in HgI2. These measurements show that silver is unacceptable as an electrode material for mercuric iodide x-ray and gamma-ray detector applications. In addition, they reveal that caution must be taken during handling of mercuric iodide source material, crystals, and detectors to avoid contact with silver, silver compounds, or with any material that contains silver as a contaminant.

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New development of HgI2 X-ray and soft gamma ray detector for synchrotron radiation research and dosimetry applications

Sensors and Actuators A Physical ◽

10.1016/0924-4247(92)80028-2 ◽

1992 ◽

Vol 32 (1-3) ◽

pp. 455-463 ◽

Cited By ~ 2

Author(s):

Gianpiero Gervino ◽

Eugenio Monticone

Keyword(s):

Synchrotron Radiation ◽

Gamma Ray ◽

X Ray ◽

New Development ◽

Gamma Ray Detector ◽

Radiation Research

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Growth and Scintillation Properties of Directionally Solidified Ce:LaBr3/AEBr2 (AE = Mg, Ca, Sr, Ba) Eutectic System

Crystals ◽

10.3390/cryst10070584 ◽

2020 ◽

Vol 10 (7) ◽

pp. 584 ◽

Cited By ~ 1

Author(s):

Kyoung Jin Kim ◽

Yuki Furuya ◽

Kei Kamada ◽

Rikito Murakami ◽

Vladimir V. Kochurikhin ◽

...

Keyword(s):

Optical Fiber ◽

Decay Time ◽

Gamma Ray ◽

Light Yield ◽

Fiber Bundles ◽

Eutectic System ◽

Directionally Solidified ◽

X Ray ◽

Scintillation Decay Time ◽

Ionic Size

Ce-doped LaBr3/AEBr2 (AE = Mg, Ca, Sr, Ba) eutectics were grown using the Bridgman–Stockbarger (BS) method in quartz ampoules. The eutectics (AE = Mg and Ca) showed optical transparency like optical fiber bundles. A grown Ce-doped LaBr3/MgBr2 eutectic shows a 355 nm emission ascribed to Ce3+ 4f-5d transition under X-ray excitation. The smaller the ionic size of AE, the higher the light yield of the sample was. The light yield of Ce:LaBr3/MgBr2 was 34,300 photon/MeV, which is higher than Ce:LYSO standard. Scintillation decay time under 662 keV gamma-ray excitation was 18.8 ns.

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PUC Program: the pulse pile up correction for X-ray and gamma ray spectrometry

Canadian Journal of Physics ◽

10.1139/cjp-2019-0431 ◽

2020 ◽

Vol 98 (9) ◽

pp. 877-882

Author(s):

S.M. Karabıdak ◽

S. Kaya

Keyword(s):

Gamma Ray ◽

Systems Design ◽

Main Peak ◽

Gamma Ray Spectrometry ◽

Background Count ◽

X Ray ◽

Quantitative Accuracy ◽

Pile Up ◽

Gamma Ray Detector ◽

Time Limitations

Pile up and dead time are two important corrections in the analysis of X-ray and gamma ray spectra. The most important of these is pile up correction because these peaks do not really exist in the spectra; they only seem to exist. For this reason, these peaks affect both the qualitative and quantitative accuracy of the analysis. In addition, the pile up pulses forming the pile up peaks increase the background count in the spectrum. Companies that produce X-ray or gamma ray detector systems design pile up reject circuits and integrate them into detector systems to prevent these pulses. These circuits have time limitations because they are made up of electronic devices. For this reason, the pile up problem cannot be solved completely in these circuits. Therefore, mathematical models based on a statistical approach are needed. Such a model was developed in this study. A computer program based on this model was developed. This developed program has been applied to X-ray and gamma ray spectra. It has been shown that this model provides about 2% correction in the main peak regions and significantly reduces background counts.

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