NIST Standard Reference Database 164

 
NIST Database of Cross Sections for Inner-Shell Ionization by Electron or Positron Impact Version 1.0

Last Update to Data Content: 2014    DOI: http://dx.doi.org/10.18434/T4N881

This database provides cross sections for ionization of the K shell and of the L and M subshells of neutral atoms of the elements, from hydrogen to einsteinium, by electron and positron impact. These cross sections are available for projectile kinetic energies that extend from the ionization threshold (the binding energy of the active shell) up to 1 GeV. The cross sections were calculated from a combination of the relativistic distorted-wave and the plane-wave Born approximations using computer programs written by Bote and Salvat [1]. Simple parameterizations have been published of the cross sections as functions of projectile kinetic energy, accurate to about 1 %; these analytical formulae can be used for rapid evaluation within a computer program [2]. Extensive comparisons have been made of the calculated cross sections for inner-shell ionization by electron impact with available experimental data where it was found that the overall root-mean-square deviation between measured and calculated cross sections was 10.9 % [3]. No evaluations have yet been made of the calculated cross sections for inner-shell ionization by positrons because of the paucity of experimental data. Nevertheless, it is believed that the algorithms for the latter calculations [1] have been validated by the comparisons between calculated and measured cross sections for inner-shell ionization by electron impact.

A Java graphical user interface (GUI) is provided to visualize the inner-shell ionization cross sections for a selected element as a function of projectile energy. This GUI is also used to visualize derived quantities (vacancy-production cross sections, Auger and x-ray emission cross sections) and to export cross-section tables as formatted ASCII files.

Cross sections for the removal of atomic inner-shell electrons by electron impact are needed in many branches of physics including atomic physics, plasma physics, radiation physics, materials analysis by electron-probe microanalysis (EPMA), surface analysis by Auger-electron spectroscopy (AES), and thin-film analysis by electron energy-loss spectroscopy. For example, these cross sections are utilized in Monte Carlo simulations of EPMA and AES measurements, particularly to derive correction factors to account for diminished or enhanced EPMA and AES signal intensities from heterogeneous specimens.  

System Requirements:
Any computer with the Java Runtime Environment (JRE) installed. This software is available for free download at http://www.java.com. Detailed supporting information is available on this site. Two files containing the database can be downloaded. The first of these is the Java file (NIST164.jar) that can be run on any computer with the JRE. The second file (WIN_NIST164.ZIP) contains a compressed installer so that Windows users can, if they wish, install the database on their computers; these installations also require the JRE.

Price: No charge.

Click here to download.

Please click here to view the PDF version of the User's Guide.

For more information please contact

Standard Reference Data Program
National Institute of Standards and Technology
100 Bureau Drive, Stop 2300
Gaithersburg, MD 20899-2310
(301) 975-2200 (VOICE); email: data [at] nist.gov (data[at]nist[dot]gov)

The scientific contact for the database is

Cedric Powell
Materials Measurement Science Division
National Institute of Standards and Technology
100 Bureau Drive, Stop 8370
Gaithersburg, MD 20899-8370
(301) 975-2534 (VOICE); email: cedric.powell [at] nist.gov (cedric[dot]powell[at]nist[dot]gov) 

[1]D. Bote and F. Salvat, Phys. Rev. A 77, 042701 (2008). 

[2]D. Bote, F. Salvat, A. Jablonski, and C. J. Powell, At. Data and Nucl. Data Tables 96, 871 (2009); ibid. 97, 186 (2011). 

[3]X. Llovet, C. J. Powell, A. Jablonski, and F. Salvat, "Cross Sections for Inner-Shell Ionization by Electron Impact," J. Phys. Chem. Ref. Data 43, 013102 (2014).

Keywords: atomic physics; Auger-electron spectroscopy; electron energy-loss spectroscopy; inner-shell ionization cross sections; electron-probe microanalysis; plasma physics; radiation physics; surface analysis; thin-film analysis; vacancy-production cross sections; x-ray emission cross sections