View source for Absolute scattering cross-section

The '''absolute scattering''' is the [[scattering intensity]] given in correct absolute units (as opposed to relative unites); from this quantity one can make quantify certain values (amount of material, molecular weight, etc.).

The easiest way to obtain absolute scattering is to measure a known standard (glassy carbon, water, etc.). In [[small-angle scattering]]:

:<math>
I(q) = I_0 \Omega t e^{- \mu t} \frac{ \mathrm{d} \Sigma } {\mathrm{d} \Omega} (q)
</math>

Where:
* I(q) is the [[scattering intensity]], in arbitrary units
* I_0 is the apparent source intensity (incident beam), in arbitrary units
* <math>\Omega</math> is the solid angle subtended by detector
* ''t'' is sample thickness
* <math>\scriptstyle \mu</math> is the linear [[absorption]] coefficient
* <math> \mathrm{d} \Sigma / \mathrm{d} \Omega </math> is the differential scattering cross-section per unit volume per unit solid angle (units cm<sup>−1</math>)

==See Also==
* ''J. Appl. Cryst.'' '''1972''', 5, 315-324.
* ''J. Appl. Cryst.'' '''1983''', 16, 473-478.
* ''Acta Metall. Mater.'' '''1991''', 39, 11, 2477-2487.