.. _xrf_modelling:

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Modelling XRF Data
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X-ray fluorescence (XRF) is the emission of X-rays of well-defined
energies that correspond to the known electronic enery levels of
atoms.  This phenomenon is closely associated to the quantum
understanding of atom and the use of X-rays of certain characteristic
energies to identify the presence of particular elements has been used
very soon after the discovery of X-rays.  While the basic XRF
phenomenon and the use of X-ray emission to identify the presence of
certain atomic species are well understood, the quantivative analysis
of X-ray fluorescence spectra to accurately determine atomic
concentrations is a bit complicated by several different factors.
With these complicating factors accounted for, accurate elemental
abundances can be extracted from XRF data.  Here, we'll cover some of
the details of what makes XRF analysis somewhat challenging and
discuss how to use Larch to analyze XRF data to extract quantitative
values for concentrations.
