The effects of pressure on X-ray fluorescence analyses: pXRF under high altitude conditions

2018 ◽  
Vol 33 (5) ◽  
pp. 792-798 ◽  
Author(s):  
Javier Merrill ◽  
Victor Montenegro ◽  
Michael F. Gazley ◽  
Leandro Voisin
Keyword(s):  
High Altitude ◽  
Atomic Weight ◽  
Low Energy ◽  
X Rays ◽  
X Ray ◽  
Air Density

As altitude increases, air density decreases, and the physics of X-rays being transmitted through air mean that the transmission of low-energy X-rays increases and accordingly the transmission effectiveness of low-atomic weight elements (e.g. Mg, Al, and Si) also increases. Here we assess the performance of pXRF units across a range of pressures.

scholarly journals The use of fricke dosimetry for low energy x-rays

2006 ◽  
Vol 49 (spe) ◽  
pp. 17-23 ◽  
Author(s):  
Carlos de Austerlitz ◽  
Viviane Souza ◽  
Heldio Pereira Villar ◽  
Aloisio Cordilha
Keyword(s):  
Ionization Chamber ◽  
Parallel Plate ◽  
Low Energy ◽  
Calibration Factor ◽  
X Rays ◽  
Measuring Systems ◽  
X Ray ◽  
Dose Measurements

The performance of four X-ray qualities generated in a Pantak X-ray machine operating at 30-100 kV was determined with a parallel-plate ionization chamber and a Fricke dosimeter. X-ray qualities used were those recommended by Deutsch Internationale Normung DIN 6809 and dose measurements were carried out with Plexiglas® simulators. Results have shown that the Fricke dosimeter can be used not only for soft X-ray dosimetry, but also for the maintenance of low-energy measuring systems' calibration factor.

SOFT X-RAY EMISSION IN THE (1.0–1.5 KEV) WINDOW WITH NITROGEN FILLING IN A LOW ENERGY PLASMA FOCUS

2002 ◽  
Vol 16 (09) ◽  
pp. 309-318 ◽  
Author(s):  
M. SHAFIQ ◽  
SARTAJ ◽  
S. HUSSAIN ◽  
M. SHARIF ◽  
S. AHMAD ◽  
...  
Keyword(s):  
Plasma Focus ◽  
Pressure Range ◽  
Filling Pressure ◽  
Pinhole Camera ◽  
Low Energy ◽  
X Rays ◽  
System Efficiency ◽  
Current Sheath ◽  
Pin Diodes ◽  
X Ray

A study of soft X-ray emission in the 1.0–1.5 keV energy range from a low energy (1.15 kJ) plasma focus has been conducted. X-rays are detected with the combination of Quantrad Si PIN-diodes masked with Al (50 μm), Mg (100 μm) and Ni (17.5 μm) filters and with a pinhole camera. The X-ray flux is found to be measurable within the pressure range of 0.1–1.0 mbar nitrogen. In the 1.0–1.3 keV and 1.0–1.5 keV windows, the X-ray yield in 4π-geometry is 1.03 J and 14.0-J, respectively, at a filling pressure of 0.25 mbar and the corresponding efficiencies are 0.04% and 1.22%. The total X-ray emission in 4π-geometry is 21.8 J, which corresponds to the system efficiency of about 1.9%. The X-ray emission is found dominantly as a result of the interaction of energetic electrons in the current sheath with the anode tip. Images recorded by the pinhole camera confirm the emission of X-rays from the tip of the anode.

Exosat Observations of H2252−035: Pulse Phase and Orbital Phase Dependent Low Energy Absorption and Iron Line Emission

1987 ◽  
Vol 93 ◽  
pp. 281-292
Author(s):  
W. Pietsch ◽  
W. Voges ◽  
E. Kendziorra ◽  
M. Pakull
Keyword(s):  
Energy Absorption ◽  
Line Emission ◽  
Low Energy ◽  
Gas Absorption ◽  
X Rays ◽  
Medium Energy ◽  
Iron Line ◽  
X Ray ◽  
Low Energies ◽  
Optical Light Curve

AbstractThe 805 sec pulsing X-ray source H2252−035 has been observed for 7 h on September 14/15 and on September 17, 1983 in X-rays with the low energy telescope and the medium energy detectors of EXOSAT. While below 2 keV the semiamplitude of the 805 s pulses is ~ 100% in the 2.3–7.9 keV band it is only ~ 40%. X-ray dips that are more pronounced in low energies occur simultaneously with the orbital minimum of the optical light curve. The medium energy spectra during dips with respect to the non dip spectrum can be explained by just enhanced cold gas absorption of an additional absorbing column of 2 1022 cm−2. Model spectra for the 805 s minimum have to include a strong iron emission line at 6.55 keV with an equivalent width of 3 keV in addition to a reduced continuum intensity (radiating area) and enhanced low energy absorption.

Low-energy cosmic X-ray measurements

1969 ◽  
Vol 47 (23) ◽  
pp. 2651-2666 ◽  
Author(s):  
A. J. Baxter ◽  
B. G. Wilson ◽  
D. W. Green
Keyword(s):  
Spectral Analysis ◽  
Energy Range ◽  
Crab Nebula ◽  
Spectral Characteristics ◽  
Low Energy ◽  
Data Recovery ◽  
X Rays ◽  
X Ray ◽  
Recovery System ◽  
The Crab Nebula

An experiment is described to investigate cosmic X rays in the energy range 0.25–12 keV. The data-recovery system and methods of spectral analysis are considered. Results are presented for the energy spectrum of the diffuse X-ray component and its distribution over the northern sky down to 1.6 keV with a limited extension at 0.27 keV.In the energy range 1.6 to 12 keV, the spectrum is represented by:[Formula: see text]although separate analyses indicate a flattening below 4.5 keV to give:[Formula: see text]and[Formula: see text]At the lowest energies, the flux appears to increase more rapidly and exhibits some anisotropy in arrival directions related to the gross galactic structure. Spectral characteristics of the Crab Nebula and Cygnus X-2 have also been determined.

scholarly journals Soft X-ray absorption spectroscopy in the low-energy region explored using an argon gas window

2020 ◽  
Vol 27 (4) ◽  
pp. 959-962
Author(s):  
Masanari Nagasaka
Keyword(s):  
Absorption Spectroscopy ◽  
Energy Region ◽  
Low Energy ◽  
X Rays ◽  
Argon Gas ◽  
X Ray ◽  
First Order ◽  
Helium Gas ◽  
Transmission Window ◽  
X Ray Absorption

The soft X-ray region below 200 eV is important for investigating chemical and biological phenomena since it covers K-edges of Li and B and L-edges of Si, P, S and Cl. Helium gas is generally used as the soft X-ray transmission window for soft X-ray absorption spectroscopy (XAS) under atmospheric conditions. However, the helium gas window cannot be applied to XAS in the low-energy region since transmitted soft X-rays mostly consist of high-order X-rays due to the low transmission of first-order X-rays. In this study, the argon gas window is proposed as a new soft X-ray transmission window in the low-energy region. High-order X-rays are removed by the absorption of the Ar L-edge (240 eV), and first-order X-rays become the major contribution of transmitted soft X-rays in the low-energy region. Under atmospheric argon conditions, the double-excitation Rydberg series of helium gas (60 eV), Si L-edge XAS of an Si3N4 membrane (100 eV) and S L-edge XAS of dimethyl sulfoxide gas (170 eV) are successfully measured, indicating that the argon gas window is effective for soft X-ray transmission in the low-energy region from 60 eV to 240 eV.

scholarly journals Optimalisasi Penggunaan Variasi Filter Pada Pesawat Sinar-X Mobile Guna Mencapai Nilai Entrance Skin Exposure (Ese) Sesuai Organ Pemeriksaan

2020 ◽  
Vol 5 ◽  
Author(s):  
Oki Dewi Pamungkas ◽  
Utari Utari ◽  
Suharyana Suharyana ◽  
Riyatun Riyatun ◽  
Nining Hargiani
Keyword(s):  
Tolerance Limit ◽  
Low Energy ◽  
X Rays ◽  
Tolerance Limits ◽  
Tube Voltage ◽  
X Ray ◽  
Skin Exposure ◽  
Measurement Results ◽  
Irradiation Field ◽  
Field Area

<p class="AbstractEnglish"><strong><span lang="EN-GB">Abstract:</span></strong><span lang="EN-GB"> This study was to determine the effect of variations in the type and thickness of the filter on the ESE and HVL values. The use of filters aims to eliminate low energy X-rays, increase effective energy, and reduce dose acceptance to patients. This variation of Al with Cu and Al with Zn filters uses a voltage (70, 80, and 90) kV, 20 mAs, 100 cm SSD, and an irradiation field area of 10 cm x 10 cm. The result of measuring the consistency of the X-ray tube voltage has the largest error value of 4.93%. At a voltage of 90 kV, the measurement results of the variation of Al filter with Cu thickness of 0.2 mm and 0.3 mm and Al filter with Zn thickness of 0.25 mm and 0.50 mm are within the tolerance limits of the thorax examination organ. While the measurement results of the Al filter variants with a Cu thickness of 0.4 mm and an Al filter with a Zn thickness of 0.75 mm are within the tolerance limit of the cranium examination organ. The ESE half value can use 3.03 mm Al, equivalent to 0.135 mm Cu or 0.22 mm Zn.</span></p><p class="AbstractEnglish"><span lang="EN-GB"><strong>Abstrak:</strong> Penelitian ini untuk mengetahui pengaruh variasi jenis dan ketebalan filter terhadap nilai ESE dan HVL. Penggunaan filter bertujuan untuk mengeliminasi sinar-X energi rendah, meningkatkan energi efektif, dan mengurangi penerimaan dosis pada pasien. Variasi filter Al dengan Cu dan Al dengan Zn ini menggunakan tegangan (70, 80, dan 90) kV, 20 mAs, SSD 100 cm, dan luas lapangan penyinaran 10 cm x 10 cm. Hasil pengukuran konsistensi tegangan tabung sinar-X memiliki nilai <em>error</em> terbesar 4,93%. Pada tegangan 90 kV hasil pengukuran variasi filter Al dengan Cu ketebalan 0,2 mm dan 0,3 mm dan filter Al dengan Zn ketebalan 0,25 mm dan 0,50 mm dalam batas toleransi organ pemeriksaan <em>thorax</em>. Sedangkan hasil pengukuran varisi filter Al dengan Cu ketebalan 0,4 mm dan filter Al dengan Zn ketebalan 0,75 mm dalam batas toleransi organ pemeriksaan <em>cranium</em>. Nilai setengah ESE dapat menggunakan 3,03 mm Al, setara dengan 0,135 mm Cu atau 0,22 mm Zn.</span></p>

scholarly journals Detection of Low-Energy X-rays Using YSO Scintillation Crystal Arrays for GRB Experiments

Universe ◽  
2021 ◽  
Vol 7 (11) ◽  
pp. 396
Author(s):  
Minbin Kim ◽  
Jakub Ripa ◽  
Il H. Park ◽  
Vitaly Bogomolov ◽  
Søren Brandt ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Low Earth Orbit ◽  
Low Energy ◽  
X Rays ◽  
Engineering Model ◽  
Scintillation Crystal ◽  
X Ray ◽  
Detector Materials ◽  
Flight Model ◽  
Intrinsic Background

We developed an X-ray detector using 36 arrays, each consisting of a 64-pixellated yttrium oxyorthosilicate (YSO) scintillation crystal and a 64-channel multi-anode photomultiplier tube. The X-ray detector was designed to detect X-rays with energies lower than 10 keV, primarily with the aim of localizing gamma-ray bursts (GRBs). YSO crystals have no intrinsic background, which is advantageous for increasing low-energy sensitivity. The fabricated detector was integrated into UBAT, the payload of the Ultra-Fast Flash Observatory (UFFO)/Lomonosov for GRB observation. The UFFO was successfully operated in space in a low-Earth orbit. In this paper, we present the responses of the X-ray detector of the UBAT engineering model identical to the flight model, using 241Am and 55Fe radioactive sources and an Amptek X-ray tube. We found that the X-ray detector can measure energies lower than 5 keV. As such, we expect YSO crystals to be good candidates for the X-ray detector materials for future GRB missions.

scholarly journals Low Z Elements of High Grade Metamorphic Rocks by PIXE Analysis – A Comprehensive Review

2020 ◽  
Author(s):  
Avupati Venkata Surya Satyanarayana ◽  
Mokka Jagannadha Rao ◽  
Byreddy Seetharami Reddy
Keyword(s):  
Cross Section ◽  
Analytical Techniques ◽  
Thick Target ◽  
Light Energy ◽  
Low Energy ◽  
High Grade ◽  
X Rays ◽  
Pixe Analysis ◽  
X Ray ◽  
Line Intensities

Abstract. The majority of PIXE analytical study on geosciences has used 3 MeV proton beams for excitation and these studies generally uses the K-X-rays for low Z elements and L-X-rays for high Z elements. The present study of resulting spectra of metamorphic high grade rocks like charnockite can require striping techniques to resolve interference problems between low and high Z elements on the applications of light energy-PIXE using Si (Li) detector. In all forms of X-ray analysis, including thick-target light energy-PIXE, the X-ray signal is a dependent of the ionization cross section and for low-energy protons, the cross section is high for the K shells of light elements and the L shells of heavy elements in charnockite rock providing sufficient fluorescent yield for analytical purposes. For Z > 55, 3 MeV protons cannot ionize K-shell electrons and analysis depends on the use of L-X-ray lines in charnockite rock. Such L-X-ray spectra are complicated and can be affected by interferences K-X-rays from low Z elements. The low Z elements present in the charnockite were identified by previous complementary analytical techniques, but not identified in this study due to the above PIXE experiment limitations, and also particularly due to the dimensions of Si (Li) detector because of low energy K-X-rays of the elements absorbed by the detector window. Both interferences complexity and detector efficiency can lead to difficulties and ambiguity in the interpretation of spectra of low Z charnockite composition, a problem that is exacerbated by uncertainty in relative K-X-ray line intensities of low Z elements. From this investigation, the light energy-PIXE is ideal for the analysis of low Z 

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