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Calculating the concentration of radon?

  1. Sep 2, 2010 #1
    Hello people, I'm needing help in calculating data or treating the data. I get measures of counts vs channel, using a silicon detector for detecting radon progeny. These peaks are Po218 and Po214, now how obtain or how understand... obtaining the concentration of radon?

    http://a.imageshack.us/img837/1483/graph02.png [Broken]

    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Sep 2, 2010 #2


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    It would help if one attaches smaller images or uses an external image storage system.

    One must use the counts, decay constant and time to determine the number of radionuclide collected.

    Bascially one has to integrate the equation for N(t) of each nuclide and relate the number of atoms back to the number of Radon atoms.

    The concentration comes from the continuity equation integrated over time.

    The number of Rn atoms is just the number in the volume of air sampled over time times the concentration. The concentration is related to the decay, but keep in mind, the decays related only to that amount detected. One also has to relate that to the amont that didn't decay.
  4. Sep 2, 2010 #3
    Thank you Professor, I am understanding a little more, I'm not a good student but I understand things. Analyzing the case of Po-218, for example.

    Now, I have: counts, decay constant and time to determine the number of radionuclide collected.

    [PLAIN]http://a.imageshack.us/img36/1310/dibujofofm.png[/CENTER] [Broken]

    And also I calculate Are = Integrate(Data, counts, channel) from 250 to 350 channel, I'm obtaining and What are type of numerical integral use?, I have use now "Trapezoidal numerical integration", for test. Is correct it? Can I use other?

    [PLAIN]http://a.imageshack.us/img6/739/graph03.png[/CENTER] [Broken]

    Later, I have Are = counts*channel in time. this value is?

    grgrgr sorry profesor, I'm to little donkey in it.​
    Last edited by a moderator: May 4, 2017
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