An accuracy assessment of photo-ionization cross-section datasets for 1–2 keV x-rays in light elements using PIXE

2013 ◽  
Vol 46 (18) ◽  
pp. 185602 ◽  
Author(s):  
C M Heirwegh ◽  
I Pradler ◽  
J L Campbell
Keyword(s):  
Cross Section ◽  
Ionization Cross Section ◽  
Accuracy Assessment ◽  
X Rays ◽  
Light Elements ◽  
Ionization Cross ◽  
Photo Ionization

α- Excited Auger Spectra

1969 ◽  
Vol 13 ◽  
pp. 418-425
Author(s):  
L. I Yin ◽  
L. Adler ◽  
R. E. Lamothe
Keyword(s):  
Cross Section ◽  
Ionization Cross Section ◽  
Auger Spectroscopy ◽  
Low Energy ◽  
Vacuum System ◽  
Light Elements ◽  
Ionization Cross ◽  
High Ionization ◽  
Auger Spectra

The possibility of obtaining Auger spectra excited by a Po 210 α-source has been investigated. The obvious advantages in the use of radioactive α-sources are simplicity, stability, and high ionization cross section for light elements. Typical spectra obtained with this method, as well as parameters affecting the characteristics of these spectra, are presented and discussed The following observations have been made: the intense low energy continuum background make it difficult to detect the presence of Auger lines in this region; the abundance of Auger lines in the above region makes identification difficult; the intensity of higher energy Auger lines is too low to be observed with the present α-source and low vacuum system; thus the practicability of α-excited Auger spectroscopy will need further investigation.

The photo-ionization cross-section of neon

1953 ◽  
Vol 220 (1140) ◽  
pp. 71-76 ◽  
Keyword(s):  
Cross Section ◽  
Ionization Cross Section ◽  
Wave Length ◽  
Grazing Incidence ◽  
Absorption Coefficients ◽  
Ionization Cross ◽  
Ionization Limit ◽  
Resonance Transitions ◽  
Photo Ionization ◽  
Dipole Length

The absorption of radiation of wave-length between 230 and 800 Å in neon was measured photometrically in a grazing incidence vacuum spectrograph. For wave-lengths longer than that corresponding to the first ionization limit the absorption coefficients were found to be zero except for photo-excitation of resonance transitions. Two sharp absorption edges were observed at 575 and 256 Å corresponding to the L 3 - and L 1 -edges respectively with a flat maximum between them. The photo-ionization cross-section at the first ionization limit was found to be 5⋅4 x 10 -18 cm 2 independent of the pressure between 50 and 500 μ ; this should be compared with the theoretical value of 5⋅8 x 10 -18 cm 2 obtained by Seaton using a dipole-length approximation. Between 575 and 400 Å the calculated and experimental curves agreed closely within the limits of measurement.

PIXE MICROANALYSIS OF VERY LOW Z ELEMENTS BY SUB MeV PROTON BEAM

1993 ◽  
Vol 03 (02) ◽  
pp. 109-120 ◽  
Author(s):  
USAMA M. EL-GHAWI
Keyword(s):  
Experimental Data ◽  
Proton Beam ◽  
Cross Section ◽  
Ionization Cross Section ◽  
Theoretical Calculations ◽  
X Rays ◽  
Ionization Cross ◽  
Ge Detector ◽  
Minimum Detection Limits ◽  
Modified Theory

Analysis of very low Z elements between Be and Si using sub MeV proton beam is explored based on theoretical calculations and supported by experimental data. With the availability of the new LE Ge detector, Be K α X-rays can be recorded with reasonable efficiency and high resolution. PWBA and the modified theory, ECPSSR, have been used for ionization cross-section calculation. Minimum detection limits (MDL’s) for thin target conditions are presented in the energy range of 150–2500 keV.

scholarly journals The quantal calculation of the photo-ionization cross-section of atomic potassium

1947 ◽  
Vol 188 (1014) ◽  
pp. 350-357 ◽  
Keyword(s):  
Cross Section ◽  
Ionization Cross Section ◽  
Great Sensitivity ◽  
Wave Functions ◽  
Laboratory Measurement ◽  
Frequency Curve ◽  
Ionization Cross ◽  
The Cross ◽  
Photo Ionization

The photo-ionization of atomic potassium is investigated using quantal methods. Emphasis is laid on the great sensitivity of the cross-section to the wave functions employed. The general features of the cross-section as revealed by the laboratory measurement can be understood. To explain the finite minimum observed in the cross-section-frequency curve it is necessary to take into account non-separability effects.

Sign in / Sign up

Export Citation Format

Share Document