ANGLE 5 FAQ

Detector

No, one copy will be enough. Angle has no limitations regarding the number of detectors you can define.

Of course. You can use Angle with any semiconductor (Ge) or scintillation (NaI) detector, regardless of the manufacturer. You just need to have a detector datasheet showing the characteristic detector dimensions and materials used.

No. The only thing you need for characterization is the detector datasheet showing the detector dimensions and materials used. Just enter these data in Angle and your detector is characterized immediately! Of course, in order to get the final result, i.e. to calculate detector efficiencies for particular counting arrangements, you need, in addition, to experimentally obtain a reference efficiency curve for your detector (efficiency transfer principle).

Indeed, there is no exact/consistent terminology in the literature and among manufacturers for particular detector construction details – different names are often used for the same thing. For example, “housing” could be also a “mount cap”, “inactive Ge layer” could be named “dead layer” or “outside contact layer” etc. In order to avoid ambiguity/confusion/misunderstanding, Angle always – while entering/editing/reviewing the data – displays a schematic drawing representing the data being currently entered. While entering the dimensions, a red dimension line is showed on the illustration indicating the required dimension. Thus, it is important what is actually indicated this way on the detector drawing, and not what it is called.

Yes. You can define up to four additional absorbing layers in your geometry. Additional absorbing layer is any material gamma-rays encounter on their way from source to detector. For each layer you can define its top and side (relative to the detector) thickness and material.

No. Just choose the detector you would like to use, click “Edit”, change whatever you want, click the “Save as” button and give a name to the new detector.

This can also be applied to simply vary the parameters of the same detector towards its better characterization (“optimization”) – for example, to estimate the real values of some parameters which are not directly accessible/measurable (dead layers, vacuum dimensions) by comparing Angle calculations with experimental data (measurements).

Technically, all cylindrical detectors have similar configurations. You can, without any worry, use the option for the equivalent coaxial detector (e.g. “closed-end coaxial”), just be sure to enter the correct dimensions.

All GMX type detectors belong to “Closed-end coaxial HPGe” in Angle detector specification – they essentially have the same configuration. If the detector is made of (high purity) Germanium, then just choose the one which configuration corresponds to those of your detectors (consult the drawing Angle provides).

No. Demo detectors are there for demonstration purposes and you cannot change their parameters.

In principle, when detector characteristics change (worsen) due to ageing (dead layer drifting), then efficiency curve changes/shifts as well, normally to lower values, and especially at lower energies. You should just re-calibrate your detector, obtaining a new reference efficiency curve (REC) and go on. That’s all!

Angle does not support that. However, this effect usually does not have any dramatic effect. Recommended reading: Literature [17].