Eff. & En. Calibrations

[FRAMEP@ORAU.GOV]

A few additional thoughts:

Even with an energy calibration (versus an efficiency calibration) the
relationship can't be expected to be linear at high energies. As such, it
would be desirable to have a calibration point every 200 kev if possible.
Certainly, that would also be true for an efficiency calibration. 

Assuming we are doing quantitative work and need an efficiency
calibration, the source should be relatively long lived and NIST traceable
(I understand that there is now an ANSI standard that defines NIST
traceable).

ANSI N42.14-1991 is almost indispensible in this regard "Calibration and
Use of Germanium Spectrometers for the Measurement of Gamma Ray
Emission Rates of Radionuclides"  It includes guidance for efficiency
calibrations above 2Mev.
 
If we are trying to do good work here, something like the Bi-214 I
mentioned in my previous post is a potential problem because of cascade
summing counting losses at small source-detector distances.

Paul Frame
Professional Training Programs
ORISE
framep@orau.gov