scholarly journals How do Uncertainties in Atomic Parameters Influence Theoretical Predictions of X-Ray Production Cross Sections By Proton Impact?

2020 ◽  
Vol 7 (2) ◽  
pp. 71-76
Author(s):  
J Miranda
Keyword(s):  
Cross Sections ◽  
Transition Probabilities ◽  
Production Cross ◽  
Emission Rates ◽  
X Rays ◽  
X Ray ◽  
Proton Impact ◽  
Analytical Technique ◽  
Ionization Cross Sections ◽  
Atomic Parameters

The emission of characteristic X-rays induced by proton impact is a phenomenon known since the first half of the 20th century. Its more widely known application is the analytical technique Particle Induced X-ray Emission (PIXE). Several models have been developed to calculate, first, ionization cross sections and then the subsequent X-ray production cross sections. However, to carry out the comparisons of these predictions with experimental data it is necessary to use atomic parameters databases (fluorescence yields, Coster-Kronig transition probabilities, emission rates) that also have experimental uncertainties. In this work it is demonstrated how these values do not allow to decide which model describes more accurately the cross sections, due to a final “theoretical uncertainty” obtained through the propagation of the original uncertainties.

CHOICE OF ATOMIC PARAMETERS FOR THEORETICAL CALCULATIONS OF L X-RAY PRODUCTION CROSS SECTIONS

1993 ◽  
Vol 03 (01) ◽  
pp. 45-61 ◽  
Author(s):  
RAVINDER KAUR ◽  
SATINDER SINGH
Keyword(s):  
Cross Sections ◽  
Transition Probabilities ◽  
Theoretical Calculations ◽  
Production Cross ◽  
Emission Rates ◽  
Excitation Energies ◽  
X Ray ◽  
Experimental Values ◽  
Atomic Parameters

Photon-induced L X-ray production cross sections have been calculated for even Z in the region Z=40–92 at different excitation energies. The results have been compared with the experimental values, and the effects of the choice of atomic parameters — like fluorescence yields, Coster-Kroning transition probabilities and relative emission rates — used in calculating L X-ray production cross sections have been discussed.

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.

X-RAY PRODUCTION, INNER SHELL IONIZATION AND READING’S THEOREM IN ION · ATOM COLLISIONS

1992 ◽  
Vol 02 (03) ◽  
pp. 197-209
Author(s):  
KEIZO ISHII
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Production Cross ◽  
X Rays ◽  
Ionization Cross ◽  
Heavy Charged Particles ◽  
X Ray ◽  
Inner Shell Ionization ◽  
Ionization Cross Sections ◽  
Shell Ionization

When a solid or gaseous target is bombarded with heavy charged particles, inner shell electrons of target atoms are ionized and characteristic x rays are produced. We can easily observe these x rays with a Si(Li) detector and derive inner-shell ionization cross section from the x-ray production cross sections. In this paper, we make a review of x-ray production, inner shell ionization and Reading’s theorem in light ion·atom collisions. This theorem is one of the most important ones in the ion·atom collision physics and permits precise discussion on comparison between experimental inner-shell ionization cross sections obtained with a Si(Li) detector and the calculations based on usual theories where the incident particle is assumed to interact with only one electron in an atom and the presence of other electrons is ignored.

MATRIX EFFECTS ON K-SHELL IONIZATION CROSS SECTIONS IN Al/Si ALLOYS

2002 ◽  
Vol 12 (01n02) ◽  
pp. 1-5
Author(s):  
M. NEKAB ◽  
Ch. HEITZ
Keyword(s):  
Cross Sections ◽  
Matrix Effects ◽  
Production Cross ◽  
Heavy Ion ◽  
Double Scattering ◽  
Scattering Mechanism ◽  
Ionization Cross ◽  
X Ray ◽  
Ionization Cross Sections ◽  
Shell Ionization

Thick targets consisting in Al/Si alloys were bombarded with 1.0 to 5.0 MeV Ar ions. The K X-ray production cross sections were deduced from the measured yields by using the Merzbacher-Lewis formula extended to heavy ion bombardment. The density dependence on the K X-ray production cross sections of Al and Si was observed. This phenomena can be interpreted within the molecular orbital double-scattering mechanism.

X-Ray Fluorescence Cross-Section Measurements in the Energy Range 4-18 keV

1995 ◽  
Vol 39 ◽  
pp. 845-855
Author(s):  
Krassimir N. Stoev ◽  
Joseph F. Dlouhy
Keyword(s):  
Cross Sections ◽  
Transition Probabilities ◽  
Weighted Average ◽  
Physical Parameters ◽  
Emission Rates ◽  
Excitation Energies ◽  
X Ray ◽  
Fluorescence Cross Section ◽  
Theoretical Results

K, L and M shell x-ray fluorescence cross sections have been measured for elements 11 ≤, Z ≤, 92 at excitation energies corresponding to weighted average energies of K-lines of Ti-K (4.558 keV), Fe-K (6,480 keV), Ge-K (10.024 keV), Se-K (11.391 keV) and Mo-K (17.805 keV) . The measurements were performed with an energy-dispersive x-ray spectrometer in a vacuum chamber using thin ultra-pure targets. Rh x-ray tube and secondary targets were used for excitation of x-ray radiation. The measured x-ray fluorescence cross-sections have been compared to previously published experimental and theoretical results. Presented data can be used for determination of physical parameters such as photoionization cross-sections, fluorescence yields, x-ray emission rates, Coster-Kronig transition probabilities and jump ratios.

L X-ray Production Cross Sections for Proton Impact on Fe, Cu, Zn, and Ge

2009 ◽  
Author(s):  
Sam J. Cipolla ◽  
Floyd D. McDaniel ◽  
Barney L. Doyle
Keyword(s):  
Cross Sections ◽  
Production Cross ◽  
X Ray ◽  
Proton Impact

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.

K-shell ionization cross sections of K and Lα X-ray production cross sections of I by 10–30 keV electron impact

2012 ◽  
Vol 90 (2) ◽  
pp. 125-130 ◽  
Author(s):  
Y. Wu ◽  
Z. An ◽  
Y.M. Duan ◽  
M.T. Liu ◽  
X.P. Ouyang
Keyword(s):  
Experimental Data ◽  
Electron Impact ◽  
Cross Sections ◽  
Production Cross ◽  
Carbon Substrate ◽  
Ionization Cross ◽  
X Ray ◽  
Pure Carbon ◽  
Ionization Cross Sections ◽  
Shell Ionization

The absolute K-shell ionization cross sections of K and Lα X-ray production cross sections of I by 10–30 keV electron impact have been measured. The target was prepared by evaporating a thin film of compound KI to a thick pure carbon substrate. The effects of multiple scattering of electrons penetrating the target films, electrons reflected from the thick pure carbon substrates and bremsstrahlung photons produced when incident electrons impacted on the targets were corrected by using the Monte Carlo method. For K K-shell and I L-shell X-ray characteristic peaks, the spectra were fitted using the spectrum-fitting program ALLFIT to extract the Kα and Kβ peak counts more accurately for element K, and Lα peak counts for element I. The experimental results were compared with some theoretical results developed recently and available experimental data from the literature. The experimental data for I L-shell X-ray production cross sections by 10–30 keV electron impact are given here for the first time.

Sign in / Sign up

Export Citation Format

Share Document