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asdf1
Nov29-05, 10:33 AM
filters for Co K radiation are usually made of iron oxide power. If a filter contains 5 mg Fe2O3, what is the transmission factor for the Co K(alpa) line? What is the intensity ratio of Co K(alpha) to Co K(beta) in the filtered beam?

agh... i have no idea where to start on that question...

inha
Nov29-05, 12:26 PM
At the K_a energy how much of the intensity will Fe2O3 absorb? And the same for K_b? Can you figure it out from here?

asdf1
Nov30-05, 02:27 AM
@@a you can't figure out the intensity with that limited amount of information, right?

inha
Nov30-05, 11:03 AM
You'll need the mass abs. coeffs. for the relevant energies from the x-ray data booklet or from here http://physics.nist.gov/PhysRefData/XrayMassCoef/cover.html. I don't remember if the booklet has those but the site does for sure. If you assume a cross sectional area A for the beam and require the filter to be of the same A you can solve for it's thickness and the use the good ol' Lambert-Beer law to calculate the transmittance.

asdf1
Dec1-05, 04:28 AM
thank you very much!!! :)

slo43
Nov2-11, 11:03 AM
can someone show the working out for this. Do we have to draw simultaneous equations ?