Nd L-shell x-ray emission induced by light ions

2021 ◽  
Author(s):  
Xian-Ming Zhou ◽  
Jing Wei ◽  
Rui Cheng ◽  
Yan-Hong Chen ◽  
Ce-Xiang Mei ◽  
...  
Keyword(s):  
Incident Energy ◽  
Nuclear Charge ◽  
Blue Shift ◽  
Atomic Data ◽  
X Rays ◽  
X Ray ◽  
Multiple Ionization ◽  
Light Ions ◽  
Intensity Ratios ◽  
Shell Ionization

Abstract The L-shell x ray of Nd has been obtained for 300 - 600 keV He2 + ions impacting, and compared with that produced by H+ and H2 + ions. The threshold of projectile kinetic energy for L-shell ionization of Nd is crudely verified in the energy region of about 300 - 400 keV. It is found that the energy of the distinct L-subshell x rays has a blue shift. The relative intensity ratios of Lβ1, 3, 4 and Lβ2, 15 to Lα1, 2 x-ray are enlarged compared to the atomic data, and they decrease with the increase of incident energy, and increase with increasing effective nuclear charge of the incident ions. That is interpreted by the multiple ionization of outer-shells induced by light ions.

scholarly journals Energy Dependency of Proton-Induced Outer-Shell Multiple Ionization for 48Cd and 49In

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Xianming Zhou ◽  
Jing Wei ◽  
Rui Cheng ◽  
Yanhong Chen ◽  
Yongtao Zhao ◽  
...  
Keyword(s):  
Cross Sections ◽  
Relative Intensity ◽  
Outer Shell ◽  
Atomic Data ◽  
X Rays ◽  
X Ray ◽  
Direct Ionization ◽  
Multiple Ionization ◽  
Ionization Cross Sections ◽  
The Impact

L subshell X-rays of 48Cd and 49In have been measured for the impact of protons with energies from 75 to 250 keV. Obviously, it is found that Lγ2 (abbreviation Lγ2,3 for 48Cd and Lγ2,3,4 for 49In) X-ray emission is enhanced in comparison with Lγ1 X-ray emission. The relative intensity ratios of Lγ2 to Lγ1 X-ray are larger than the atomic data and increase with decreasing proton energy. This is caused by the multiple ionization of outer-shell electrons. To verify this explanation, the enhancements for relative intensity ratio of Lι and Lβ2 to Lα X-ray in experiments are discussed, and the direct ionization cross sections of 4d, 5s, and 5p electrons are calculated using BEA theory.

Influence of X-Ray Induced Fluorescence on Energy Dispersive X-Ray Analysis of Thin Foils

1977 ◽  
Vol 35 ◽  
pp. 328-329
Author(s):  
E. A. Kenik ◽  
J. Bentley
Keyword(s):  
Thin Foil ◽  
Electron Excitation ◽  
Simple Approach ◽  
Foil Thickness ◽  
X Rays ◽  
X Ray ◽  
Hole Spectrum ◽  
Illumination System ◽  
Thin Foils ◽  
Intensity Ratios

Cliff and Lorimer (1) have proposed a simple approach to thin foil x-ray analy sis based on the ratio of x-ray peak intensities. However, there are several experimental pitfalls which must be recognized in obtaining the desired x-ray intensities. Undesirable x-ray induced fluorescence of the specimen can result from various mechanisms and leads to x-ray intensities not characteristic of electron excitation and further results in incorrect intensity ratios.In measuring the x-ray intensity ratio for NiAl as a function of foil thickness, Zaluzec and Fraser (2) found the ratio was not constant for thicknesses where absorption could be neglected. They demonstrated that this effect originated from x-ray induced fluorescence by blocking the beam with lead foil. The primary x-rays arise in the illumination system and result in varying intensity ratios and a finite x-ray spectrum even when the specimen is not intercepting the electron beam, an ‘in-hole’ spectrum. We have developed a second technique for detecting x-ray induced fluorescence based on the magnitude of the ‘in-hole’ spectrum with different filament emission currents and condenser apertures.

K shell X-ray intensity ratios, K-Li, K-L, and K-M vacancy transfer probabilities of Ba and Tl following internal conversion process

2014 ◽  
Vol 92 (11) ◽  
pp. 1489-1493 ◽  
Author(s):  
P.V. Sreevidya ◽  
S.B. Gudennavar ◽  
Daisy Joseph ◽  
S.G. Bubbly
Keyword(s):  
Beta Decay ◽  
Internal Conversion ◽  
Experimental Results ◽  
Conversion Process ◽  
X Rays ◽  
X Ray ◽  
Multichannel Analyser ◽  
Intensity Ratios

K shell X-rays of barium and thallium following internal conversion decay in Cs137 and Hg203, respectively, were detected using a Si(Li) X-ray detector coupled to PC-based 8k multichannel analyser employing the method suggested earlier by our group. The K shell X-ray intensity ratios and vacancy transfer probabilities for thallium and barium were calculated. The obtained results are compared with theoretical, semiempirical, and others’ experimental results obtained via photoionization as well as decay processes. The effects of beta decay and internal conversion on X-ray emission probabilities are discussed.

Measurement of L X-ray production cross sections and relative intensities of some lanthanide compounds depending on the temperature

2020 ◽  
Vol 108 (5) ◽  
pp. 415-423
Author(s):  
Esra Cinan ◽  
Bünyamin Aygün ◽  
M. I. Sayyed ◽  
Yüksel Özdemir
Keyword(s):  
Cross Sections ◽  
Full Width Half Maximum ◽  
Production Cross ◽  
Emission Spectra ◽  
X Rays ◽  
X Ray ◽  
Different Temperatures ◽  
Intensity Ratios ◽  
Annular Source

AbstractL X-ray intensity ratios for CeO2, Sm2(SO4)3, Ho2O3, and Yb2O3 compounds were experimentally investigated. The measurements were gauged following excitation by 59.54 keV γ-rays from a 100 mCi 241Am radioactive annular source at different temperatures in situ. Temperature change occurred between 50 °C and 400 °C. L X-ray emission spectra were obtained by using a solid-state Si(Li) X-ray detector. L X-ray production cross sections, intensity ratios, and full-width half maximum (FWHM) values for the compounds were determined by evaluating the emission spectra varying with the temperature. According to the results obtained, it was observed that Lβ1 X-rays were less influenced in comparison with Lα X-rays while Lα X-rays were also less influenced in comparison with Lβ2 X-rays.

Sky survey of high-energy cosmic X-rays and spectral information on sources in the Crab nebula, Cygnus, and Scorpius

1968 ◽  
Vol 46 (10) ◽  
pp. S409-S413 ◽  
Author(s):  
Walter H. G. Lewin ◽  
George W. Clark ◽  
William B. Smith
Keyword(s):  
Crab Nebula ◽  
High Energy ◽  
X Rays ◽  
Coma Cluster ◽  
X Ray ◽  
Sky Survey ◽  
Upper Limits ◽  
Intensity Ratios ◽  
The Crab Nebula ◽  
Made In

A complete X-ray survey of the northern sky has been made in the energy range 20–100 keV. Spectra are given for Cyg X-1 and Tau X-1. Intensity ratios (Cyg X-1/Tau X-1) of 0.84 ± 0.10 and 1.30 ± 0.25 were derived in the 20–70 keV range from data obtained on July 19, 1966 and February 13, 1967, respectively. Observations on Sco X-1 and the Coma cluster show upper limits which are quite different from results reported by other groups.

X-Ray Fluorescence Spectrometric Determination of Rare Earths in Plutonium

1968 ◽  
Vol 22 (5) ◽  
pp. 434-437 ◽  
Author(s):  
E. A. Hakkila ◽  
R. G. Hurley ◽  
G. R. Waterbury
Keyword(s):  
Rare Earths ◽  
Internal Standard ◽  
Internal Standard Method ◽  
X Rays ◽  
Measured Intensity ◽  
X Ray ◽  
Low Concentrations ◽  
Relative Standard ◽  
Intensity Ratios

Two methods were evaluated for determining rare earths in plutonium: (1) For the lighter rare earths ( Z≦66), or low concentrations of the heavier rare earths, an adjacent rare earth was added as a carrier and also as an internal standard, the rare earths were separated from plutonium by fluoride precipitation, and the measured intensity ratios for the sample and for solutions having known concentrations were compared. The Lβ1 x-rays were measured for the lighter rare earths and the Lα1 x rays for the remaining lanthanides. (2) For the heavier rare earths ( Z>66), the Lα1 x-ray intensities were measured from a nitric acid solution of the sample and compared to intensities obtained for solutions having known concentrations. The minimum concentrations that could be measured with a relative standard deviation no greater than 4% by the separation internal standard method varied from approximately 0.5% for lanthanum to 0.01% for lutetium. The direct measurement of x-ray intensity was much less sensitive. Applicability of the methods was shown by successful analyses of plutonium alloys containing dysprosium, thulium, or lutetium.

IN SITU ASSEMBLY OF ZnS NANOFIBERS WITH HIGHLY ORDERED LAMELLAR MESOSTRUCTURE

2006 ◽  
Vol 05 (02n03) ◽  
pp. 245-251 ◽  
Author(s):  
JUNPING LI ◽  
YAO XU ◽  
DONG WU ◽  
YUHAN SUN
Keyword(s):  
Electron Microscope ◽  
Thermal Analyses ◽  
Blue Shift ◽  
X Rays ◽  
Energy Dispersive Analysis ◽  
Visible Absorption ◽  
X Ray ◽  
Transmission Electron ◽  
Uv Visible

ZnS nanofibers with lamellar mesostructure could be built up from in situ generated ZnS precursors via hydrothermal routes using neutral n-alkylamines as structure-directing template and ethylene diamine tetraacetic acid (EDTA) as stabilizer. The morphology and structure of the obtained products were thoroughly investigated via scanning electron microscope (SEM), energy dispersive analysis of X-rays (EDX), transmission electron microscope (TEM), X-ray powder diffraction (XRD) and thermal analyses. HRTEM and XRD results revealed that the so-produced nanofibers were lamellar mesostructure and its framework was built of crystalline wurtzite ZnS . It was also found that the distance between the layers was proportional to the chain length of the alkylamine. The UV-visible absorption spectrum showed that the nanofibers exhibited strong quantum-confined effect with a blue shift in the band gap. Finally, a probable mechanism for the assembly of the nanofibers was also proposed.

Atomic Structure and Spectra

2021 ◽  
pp. 68-146
Author(s):  
Kannan M. Krishnan
Keyword(s):  
Photoelectron Spectroscopy ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
X Rays ◽  
X Ray ◽  
Spatially Resolved ◽  
Excitation Processes ◽  
Shell Ionization

We review the structure of atoms to describe allowed intra-atomic electronic transitions following dipole selection rules. Inner shell ionization is followed by characteristic X-ray emission or non-radiative de-excitation processes leading to Auger electrons that involve three atomic levels. Photon incidence also results in characteristic photoelectron emission, reflecting the energy distribution of the electrons in the solid. We present details of laboratory and synchrotron sources of X-rays, and discuss their detection by wavelength or energy-dispersive spectrometers, as well as microanalysis with X-ray (XRF), or electron (EPMA) incidence. Characteristic X-ray intensities are quantified in terms of composition using corrections for atomic number (Z), absorption (A), and fluorescence (F). Electron detectors use electrostatic or magnetic dispersing fields; two common designs are electrostatic hemispheric or mirror analyzers. Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS), used for surface analysis, require ultra-high vacuum. AES is a weak signal, best resolved in a derivative spectrum, shows sensitivity to the chemical state and the atomic environment, provides a spatially-resolved signal for composition mapping, and can be quantified for chemical analysis using sensitivity factors. Finally, we introduce the basics of XPS, a photon-in, electron-out technique, discussed further in §3.

X-Ray Production Cross Sections for Ti, Co, Ge, Rb and Sn by 16 - 44 Mev Oxygen Ion Bombardment

1973 ◽  
Vol 17 ◽  
pp. 445-456
Author(s):  
R. F. Chaturvedi ◽  
J. L. Duggan ◽  
T. J. Gray ◽  
C. C. Sachtleben ◽  
J. Lin
Keyword(s):  
Cross Sections ◽  
Production Cross ◽  
X Rays ◽  
X Ray ◽  
Oxygen Ions ◽  
Oxygen Ion ◽  
Theoretical Predictions ◽  
Ionization Cross Sections ◽  
Binary Encounter Approximation ◽  
Shell Ionization

AbstractAbsolute K-shell ionization cross sections were measured for Ti, Co, Ge, Rb, and Sn for incident oxygen ions from 16-44 MeV. The x-rays were measured with a high resolution Si(Li) detector (166 eV at 5.9 keV). All of the data represents cross section measurements for thin targets. The measured cross sections for these elements are compared to the theoretical predictions of the Binary Encounter Approximation (BEA). Kα/Kβratios and energy shifts were also extracted from the data. The experimental data are compared to measured cross sections for other elements to give an overview of the systematics for oxygen ion induced x-ray production cross sections in this energy range. Some comment will also be given in regard to the use of oxygen ions to measure the parameters associated with ion implanted semiconductors.

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