INVESTIGADORES
CASTELLANO Gustavo Eugenio
artículos
Título:
Review of ɸ(ρz) curves in electron probe microanalysis
Autor/es:
J. A. RIVEROS; G. CASTELLANO
Revista:
X-RAY SPECTROMETRY
Editorial:
JOHN WILEY & SONS LTD
Referencias:
Lugar: Bethesda, Maryland; Año: 1993 vol. 22 p. 3 - 10
ISSN:
0049-8246
Resumen:
Several workers have proposed different models for the
ionization distribution function (z), involving features related to the
interaction of electrons with matter, e.g. ionization cross-section,
stopping power, electron back-scattering and mass absorption
coefficients (MACs). A number of expressions have been developed for
these parameters, on which the accuracy of the correction procedures
depends. This paper presents a comparison among three of the more
successful models for (z): Packwood and Brown's Gaussian model,
the quadrilateral model proposed by Sewell et al. and Pouchou and
Pichoir's model.In order to test these models, a set
of 1547 measurements in binary samples of known composition has been
complied. Several models for the ionization cross-section have been
tested, along with different expressions for the mean ionization
potential J, in which the shell effect can be taken into account.
In addition, two possibilities for both the MACs and the electron
backscattering coefficient are available. In general, all the tested
models showed similar performances. Finally, the advantages of the
models related to basic principles over the mathematically optimized
ones, in the shape of (z) or in the parameters, are considered.