Normalization of yield data

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(corrected a typo in the DeltaOmega expression under "exceptions")
(fixed details of the solid angle factors for clusters)
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==Ge detector solid-angle corrections==
==Ge detector solid-angle corrections==
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If all of the Ge detectors span the same solid angle, then all of the data will be consistent if each count is efficiency-corrected by dividing by the relative efficiency <math>\epsilon (E_\gamma)</math> with an arbitrary overall normalization.  However, if two data sets from different detector ''[[physical_germanium_type | types]]'' are included, then the following additional correction is necessary, since Gosia calculates (OP,INTI) yield per unit Ge solid angle to be used in fits (OP,MINI).
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If all of the Ge detectors span the same solid angle, then all of the data will be consistent if each count is efficiency-corrected by dividing by the relative efficiency <math>\epsilon (E_\gamma)</math> with an arbitrary overall normalization.  However, if two data sets from different detector ''[[physical_germanium_type | types]]'' are included, then the following additional correction is necessary, since Gosia calculates (OP,INTI) yield per unit Ge solid angle and expects the same yield per unit solid angle in fitting (OP,MINI).
Gosia expects to read "corrected" yields of  
Gosia expects to read "corrected" yields of  
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In cases where the overall normalization doesn't matter, the efficiency can absorb the solid angle and be taken on a scale of 0 < efficiency < 4pi, ''but the solid angle factor must not be included twice.''
In cases where the overall normalization doesn't matter, the efficiency can absorb the solid angle and be taken on a scale of 0 < efficiency < 4pi, ''but the solid angle factor must not be included twice.''
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===Exceptions===
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===Exceptions and warnings===
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If the counts from different types of Ge detectors are being summed into one data set, and there are no other data sets (Ge detectors or arrays), then the <math>\Delta\Omega_{Ge}</math> term amounts to only an overall normalization and can be neglected.
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If the data sets are from detector clusters (see OP,RAW in the user manual), all of the Ge crystals in the cluster should be of the same physical type.  This is because Gosia gives output and expects data from the user representing the count per unit solid angle ''of the crystal type,'' not of the total cluster solid angle.
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The OP,RAW command can be used to pass data to Gosia without an efficiency correction.  The solid angle divisors are still required.
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It is not clear how to handle summed Ge clusters of ''different physical types'' in Gosia.
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The OP,RAW command can be used to pass data to Gosia without an efficiency correction and/or for summed clusters.  The solid angle divisors are still required, and for each cluster should be taken as <math>\Delta\Omega_{crystal}</math>&mdash;the solid angle of a single Ge detector in the cluster!

Revision as of 15:39, 16 June 2011

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