Files with reference efficiency curve data have a “.recx” extension. The structure of REC data is:
<referenceEfficiencyCurve name=str description=str0> <experimentalPoints> <point energy=float efficiency=float /> ... </experimentalPoints> <regions> <region start=float end=float polynomOrder=float /> ... </regions> <detector name=str /> <container Reference container specification /> <geometry Reference geometry specification /> <source Reference source specification /> </referenceEfficiencyCurve>
REC parameters contain values for experimental points, interpolation, the detector name, and a container, geometry and the source used for the reference measurement.
Experimental points, i.e. the results of the reference measurement, are defined inside the “experimentalPoints” element. Each energy-efficiency pair is represented by one “point” sub-element with two attributes: “energy” and “efficiency”.
Reference efficiency curve interpolation is specified inside the “regions” element (if the curve is interpolated, not discrete). Each region is defined by one “region” element and its attributes “start”, “end” and “polynomOrder” which define the boundary energies of the region and the polynomial order. The “start” attribute is mandatory for the first region, but it is not used in any subsequent region, since the end of one region is automatically assumed to be the start of the next one.
Angle will calculate polynomial coefficients and insert them in form of a comment for each region.
The name of the detector used for reference measurements is specified by the “name” attribute of the “detector” element.
The rest of the REC data are parameters for the reference container and geometry (if any) and the radioactive source used, the structure of which was specified earlier (see Container data specification, Geometry data specification and Source data specification).
<?xml version="1.0" encoding="utf-8"?> <angle generator="ANGLE" version="4.0" build="5.0.0.274" units="mm"> <referenceEfficiencyCurve name="Eff_curve" description="20 mL LSC vial"> <experimentalPoints> <point energy="99.45" efficiency="0.006404" /> <point energy="129.02" efficiency="0.006427" /> <point energy="277.29" efficiency="0.004213" /> <point energy="338.22" efficiency="0.003766" /> <point energy="510.52" efficiency="0.003055" /> <point energy="583.03" efficiency="0.002497" /> <point energy="755.27" efficiency="0.002089" /> <point energy="772.33" efficiency="0.002063" /> <point energy="835.41" efficiency="0.002043" /> <point energy="964.79" efficiency="0.001715" /> <point energy="968.96" efficiency="0.001654" /> </experimentalPoints> <regions> <region start="70" end="130" polynomOrder="2" /> <region end="1200" polynomOrder="2" /> </regions> <detector name="43-TN21827A" /> <container type="Cylindrical" name="20 mL plastic vial" description=""> <shape innerRadius="26" sideThickness="1" bottomThickness="1" footHeight="0" /> <material name="Plastic" /> </container> <geometry type="General" name="Plastic rings" description="Plastic rings below the container "> <holder outerRadius="10" height="20"> <cap thickness="0" /> <wall thickness="10"> <material name="Plastic" /> </wall> </holder> </geometry> <source radius="13" height="10"> <material name="Water" /> </source> </referenceEfficiencyCurve> </angle>