Rachel simulated yield output

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(Major changes reflect the output and operation of version 1.)
(Accuracy checking)
 
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===Accuracy checking===
===Accuracy checking===
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The predicted absolute counts (cross sections) for p-<math>\gamma</math> events were checked against perturbation calculations for weakly-coupled two-state systems where the perturbation method is valid.  Both the total count rates and solid angle factors have been re-checked in version 2.0.8.beta and agree with the perturbation calculations where they are applicable.
+
The predicted absolute counts (cross sections) for p-<math>\gamma</math> events were checked against perturbation calculations for weakly-coupled two-state systems where the perturbation method is valid.  Both the total count rates and solid angle factors have been re-checked in version 2.0.8.beta and agree with the perturbation calculations where they are applicable.  Many tests of fits to simulated yield data without the optional random error scatter resulted in <math>\chi^2</math> values very close to zero, as expected.
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The ''intrinsic'' efficiency has been estimated more accurately in version 2.0.8.beta.  This will make a noticeable change in the "Raw counts" column.
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The ''intrinsic'' efficiency has been estimated more accurately in version 2.0.8.beta.  This will make a noticeable change in the "Raw counts" column.
===Simulated data passed to Gosia===
===Simulated data passed to Gosia===
Note that Rachel operates Gosia such that efficiency-corrected "incident gamma" counts are passed to Gosia, but first they are divided by the solid angle of each Ge detector to match Gosia's calculation of yield per unit solid angle.  (This is true in Rachel versions >= 2.0.7.beta; in earlier versions this solid angle factor was neglected, which usually did not result in accuracy errors.)  All yields sent to Gosia are then multiplied by <math>4\pi</math> so that weak transitions have counts >=1.  This overall multiplicative constant of <math>4\pi</math> has no effect on fitting.  Refer to the page [[Normalization_of_yield_data | Normalization of yield data]] for more detail.
Note that Rachel operates Gosia such that efficiency-corrected "incident gamma" counts are passed to Gosia, but first they are divided by the solid angle of each Ge detector to match Gosia's calculation of yield per unit solid angle.  (This is true in Rachel versions >= 2.0.7.beta; in earlier versions this solid angle factor was neglected, which usually did not result in accuracy errors.)  All yields sent to Gosia are then multiplied by <math>4\pi</math> so that weak transitions have counts >=1.  This overall multiplicative constant of <math>4\pi</math> has no effect on fitting.  Refer to the page [[Normalization_of_yield_data | Normalization of yield data]] for more detail.

Latest revision as of 16:02, 28 January 2012

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