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Homework Help: Another radiation

  1. Nov 29, 2005 #1
    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...
  2. jcsd
  3. Nov 29, 2005 #2
    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?
  4. Nov 30, 2005 #3
    @@a you can't figure out the intensity with that limited amount of information, right?
  5. Nov 30, 2005 #4
    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.
  6. Dec 1, 2005 #5
    thank you very much!!! :)
  7. Nov 2, 2011 #6
    can someone show the working out for this. Do we have to draw simultaneous equations ?
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