New data base for Lα, Lβ, Lγ x-ray production by protons, new empirical fits, extraction of L-subshell ionization cross sections with various atomic parameters, and their comparison with the ECPSSR theory and its modifications: a recommendation for reliable choice of atomic parameters and ionization theory for PIXE analysis

Partial K-x ray production cross sections of dysprosium, erbium and lutetium by proton and 3He-ion impact have been measured over the incident energy range of 3-40 MeV/amu. It is found that the measured ionization cross sections become larger in comparison with the prediction of PWBA theory and agree well with the ECPSSR theory in the wide energy region. This fact means that relativistic effect of inner-shell electrons is the most predominant among many effects such as the energy loss and the Coulomb deflection of the projectile and also the effects of polarization and increased binding energy of orbital electrons in the perturbed stationary states.

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L AND M X-RAY PRODUCTION CROSS SECTIONS OF HEAVY RARF EARTH ELEMENTS IN THE 3-40 MeV/amu PROJECTILE-ENERGY RANGE

International Journal of PIXE ◽

10.1142/s0129083598000285 ◽

1998 ◽

Vol 08 (04) ◽

pp. 253-266 ◽

Cited By ~ 1

Author(s):

K. SERA ◽

K. ISHII ◽

H. ORIHARA

Keyword(s):

Energy Range ◽

Cross Sections ◽

Production Cross ◽

Projectile Energy ◽

Ionization Cross ◽

X Ray ◽

Ion Impact ◽

Ionization Cross Sections ◽

Ecpssr Theory ◽

First Time

Partial L- and M-x-ray production cross sections for Dy , Er and Lu have been systematically measured over the wide projectile-energy range of 3-40 MeV/amu for proton and 3 He -ion impact, and values of partial x-ray production cross sections were compared with those predicted by the ECPSSR theory. As the result, it is confirmed that the ECPSSR theory gives consistent ionization cross sections for each subshell in L- and M-shells. It is also found that values of x-ray transition rate are correct for Mα,β and Lα12 lines which are predominant in M and L x-ray spectra, respectively. However, it is pointed out that some of the values of x-ray transition rates must be revised, and improved values were obtained experimentally for the first time.

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L-subshell X-ray Production by 100?250 keV/a.m.u. Ions

Australian Journal of Physics ◽

10.1071/ph840475 ◽

1984 ◽

Vol 37 (5) ◽

pp. 475 ◽

Cited By ~ 10

Author(s):

MF Harrigan ◽

BM Spicer ◽

DD Cohen

Keyword(s):

Cross Sections ◽

Experimental Results ◽

Ionization Cross ◽

X Ray ◽

Theoretical Predictions ◽

Ion Velocity ◽

Ionization Cross Sections ◽

The Individual ◽

Ecpssr Theory ◽

Key Steps

Individual L-subshell ionization cross sections have been measured for bombardment of 100-200 keY H+ ions in 10 keY steps upon a thick Gd (Z = 64) target and for bombardment of 600-1000 keY He+ ions in 100 keY steps upon thick W (Z = 74) and thick and thin Au (Z = 79) targets. Experimental results for the individual L subshells are compared with the theoretical predictions of the ECPSSR theory as developed by Brandt and Lapicki. The differences are discussed as a function of the reduCi:,d ion velocity. The occurrence of collision induced intra-shell transitions is discussed as a possible source for the discrepancy between experiment and theory.

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

International Journal of PIXE ◽

10.1142/s0129083502000020 ◽

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.

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Ultrafast photodissociation of Br2: Laser-generated high-harmonic soft x-ray probing of the transient photoelectron spectra and ionization cross sections

The Journal of Chemical Physics ◽

10.1063/1.1504084 ◽

2002 ◽

Vol 117 (13) ◽

pp. 6108-6116 ◽

Cited By ~ 31

Author(s):

Lora Nugent-Glandorf ◽

Michael Scheer ◽

David A. Samuels ◽

Veronica M. Bierbaum ◽

Stephen R. Leone

Keyword(s):

Cross Sections ◽

High Harmonic ◽

Photoelectron Spectra ◽

Ionization Cross ◽

X Ray ◽

Ionization Cross Sections

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

Canadian Journal of Physics ◽

10.1139/p11-149 ◽

2012 ◽

Vol 90 (2) ◽

pp. 125-130 ◽

Cited By ~ 7

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.

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