ANGLE Advanced Efficiency Calibration Software
for High Purity Germanium Detectors

• An easy way to create HPGe efficiency calibrations for Marinelli Beakers, bottles and other sample shapes directly from a point source calibration. (No replicate standards required.)

• Reads in GammaVision point source calibration, adjusts the calibration to the new geometry, and exports the revised calibration back to GammaVision.

• WORKS WITH ANY DETECTOR. No need for expensive and time consuming “return to factory” characterization.

• Works with a wide variety of HPGe Detector types from any manufacturer – templates included.

• Works with the majority of container types commonly found in Nuclear Counting Laboratories – templates included.

• Reduces radioactive waste disposal problems and lowers lab operational costs.

Before a High Purity Germanium spectrometer is ready for use, it must be calibrated for energy and efficiency. Conventionally, the efficiency calibration is performed using a radioactive source. This source must be in a geometry that exactly mimics the container of the sample to be measured, as well as the physical make-up (matrix) of the sample. A typical laboratory could have 2, 3, or perhaps even more types of containers for holding samples. Add to this the varying types of matrices (soil, water, sludge, filters) and the cost of calibrating a detector can be condsiderable, not to mention the hazard of having to maintain so many radioactive standards. Since many of the nuclides in the calibration standard may be short lived, they must be replaced on a regular basis (a recurring cost).

ANGLE uses a single reference efficiency curve calibration, which can be performed by the user in their own counting laboratory, and information about the detector, container, geometry, and source is then added to generate the efficiency calibrations. Since only one source and one count are needed, the time and money saved adds up quickly.

ANGLE utilizes a mathematical concept of effective solid angle to derive multiple calibrations from the single reference calibration.

ANGLE has been developed over 14 years and is now fully compatible with ORTEC’s GammaVision gamma spectroscopy software.

How It Works

An easy step by step process that allows the user create efficiency calibrations in moments.

 • Using GammaVision, count a mixed gamma point source, or a series of point sources with varying isotopes, to create energy/efficiency pairs.
• Open ANGLE and enter the data for the Container, Geometry, Source, and Detector.
• Import the energy/efficiency pair data from GammaVision to ANGLE.
• ANGLE calculates a “relative efficiency curve calibration.”
• Transfer the “relative efficiency” data back to GammaVision.
• Start counting samples.

STEP 1: Use GammaVision to Create the Reference Efficiency Calibration

ORTEC’s premier Gamma Spectroscopy software package allows quick and easy calibrations. Simply create a certificate file and library for the calibration source, count the source, and use GammaVision’s automatic calibration routine to generate an efficiency curve.

Next, open ANGLE and enter parameters for sample Container, Geometry, Source configuration, and the information about the Detector.

This process can also be done while the calibration source is being counted, providing further time savings.

STEP 2: Container Information

Select and enter a container name.

ANGLE comes with some predefined container templates for ease of use. The software provides a graphical display showing the user which parameter to enter. Once the container is defined, it can be used over and over with any detector configuration.

STEP 3: Geometry Information

The Geometry information screen also utilizes the graphical display to make data entry simple.

Simply select a name for the geometry and enter in a few data points.

The software comes with predefined holder materials, or you can define your own.

Additionally, you can define or select up to 5 intercepting layers to compensate for absorption of the gamma rays.

STEP 4: Source Information

Next, enter the parameters that define your source.

ANGLE includes predefined common source materials, but also allows the user to define their own material, which can consist of one element, a mixture of elements, a compound, or even a mixture of compounds. Entering the density of the source material allows ANGLE to compensate for self absorption. This provides even more flexibility.

STEP 5: Detector Information

Enter the Detector dimensional data and other detector information about the:

            Window
            End Cap
            Vacuum housing
            Crystal housing

All of these factors come with templates for common materials, but also allow you to define them yourself.

This information must be provided by the detector manufacturer.

STEP 6: Reference Efficiency Curve Information

Once the calibration source(s) have been counted, the energy/efficiency pairs and source container/geometry data is entered into ANGLE, which then generates the relative efficiency curve calibration.

For GammaVision users, the transfer of data is quick and accurate by simply selecting the IMPORT icon.

With one click of the button, the Calibration information is transferred from GammaVision to ANGLE.

The next step is to associate this calibration with the appropriate “target” combination of Geometry, Container, and Source. In seconds Angle will generate an appropriate calibration for this configuration. From the one Reference calibration you can create any number of relative efficiency curves that match your configurations.

After you create the Relative Efficiency Calibration, simply select the newly created EXPORT button to transfer the calibration to GammaVision.

Now you are ready to count your samples – it’s that simple!

ACCURACY

There are many factors that can effect the accuracy of the results, however, with the correct entry of the information about the detector, container, geometry and source, routine applications can expect 3–4% accuracy.

With ANGLE calibration software, GammaVision-32 Advanced Spectroscopy Software, and a Single Point Source Calibration, you have an accurate alternative to purchasing and counting multiple calibration sources, saving time and money.

PREREQUISITES

Windows 2000/XP/Vista

Detailed detector dimensional and material information. (Contact the detector manufacturer.)

Detailed container dimensional and material information. (Contact the container manufacturer.)

ORDERING INFORMATION

Model                                Description
ANGLE-B32               Advanced Efficiency Calibration software for HPGe detectors
ANGLE-G32              Operators Manual for ANGLE software
ANGLE-U32              Update for ANGLE software