Difference between revisions of "X-ray absorption & fluorescence"
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Alternatively ''Attenuation Length'' is defined as the distance into a material where the x-ray beam intensity has decreased to 1 / e, or about 63% of the incident beam. The X-ray beam intensity at depth x into a material is calculated by Beer-Lambert law: | Alternatively ''Attenuation Length'' is defined as the distance into a material where the x-ray beam intensity has decreased to 1 / e, or about 63% of the incident beam. The X-ray beam intensity at depth x into a material is calculated by Beer-Lambert law: | ||
<math> | <math> | ||
\operatorname{erfc}(x) = | |||
\frac{2}{\sqrt{\pi}} \int_x^{\infty} e^{-t^2}\,dt = | |||
\frac{e^{-x^2}}{x\sqrt{\pi}}\sum_{n=0}^\infty (-1)^n \frac{(2n)!}{n!(2x)^{2n}} | |||
</math> | |||
I(x) = e^(-x/lambda) | I(x) = e^(-x/lambda) | ||
Revision as of 23:49, 28 August 2011
X-ray Absorption Information (11BM page) http://11bm.xor.aps.anl.gov/absorption.html
Absorption Length
Alternatively Attenuation Length is defined as the distance into a material where the x-ray beam intensity has decreased to 1 / e, or about 63% of the incident beam. The X-ray beam intensity at depth x into a material is calculated by Beer-Lambert law:
<math>
\operatorname{erfc}(x) =
\frac{2}{\sqrt{\pi}} \int_x^{\infty} e^{-t^2}\,dt =
\frac{e^{-x^2}}{x\sqrt{\pi}}\sum_{n=0}^\infty (-1)^n \frac{(2n)!}{n!(2x)^{2n}}
</math>
I(x) = e^(-x/lambda)
ln(1/e) = ln(e ^-x/lambda)
1 = x/Lambda
1/lamda = x
1/mu = x
