Advanced Gamma-Spectrometry Software


Angle 4 is the latest version of the long existing and well known software for semiconductor detector gamma-efficiency calculations, now also supporting scintillation ones. Angle allows for accurate determination of the activities of gamma-spectroscopic samples for which no “replicate” standard exists, in terms of geometry and matrix. Semi-empirical “efficiency transfer” (ET) approach is used, based on the effective solid angle (Ω) calculations.

Angle 4 combines advantages of both absolute (no experimental evidence, e.g. Monte Carlo calculations only) and relative (fully experimental, calibrated-source-based) methods – minimizing potential for systematic errors in the former and reducing practical limitations of the latter.

Angle 4 is a result of 28 years of development, practical experience in numerous gamma-spectrometry laboratories worldwide and constructive users’ feedback. For the list of some prominent Angle users click here.


Angle 4 is broadly applicable in:

  • environmental monitoring
  • food safety
  • nuclear industry
  • waste management
  • fuel cycle
  • nuclear decommissioning
  • regulatory control
  • laboratory quality management
  • medicine
  • health physics and radiation protection
  • emergency preparedness and response
  • homeland security
  • safeguards
  • geology and hydrology
  • research
  • education and training

Angle 4 can be used in most of counting arrangements in gamma-spectrometry practice in respect to:

  • detector types and configuration
  • source shapes and volumes
  • matrix composition
  • source-to-detector distance
  • calibration source
  • gamma energy range of interest, etc.

Angle 4 outline

Main characteristics can be summarized as:

  • Broad application range, covering the vast majority of counting situations in gamma-spectrometry related sciences and applications (environmental monitoring, nuclear industry, waste management, food safety, medicine, regulatory control, homeland security, safeguards, research, education, etc.)
  • High accuracy (uncertainties are of the order of a few percent - usually less than from other uncertainty sources in the measurement), based upon the concept of the ET and effective solid angle calculations; the latter proved to be among the most reliable efficiency determination approaches
  • Easy data manipulation with friendly and intuitive graphical user interface
  • Short computation times of the order of seconds on standard PCs (normally less than a minute)
  • Flexibility in respect with changing input parameters, which enables easy estimation of the impact of a particular parameter on the detection efficiency and, related to this
  • Teaching/training/studying aspect (e.g. in gamma-spectrometry courses), since practically all parameters characterizing the detection process are found therein, systematically grouped and easy to follow and understand
  • No need for “factory characterization” of the detector – Angle can be used with any HPGE detector; when necessary, the detector performance is easily re-validated without intervention from the vendor
  • Possibility to expand, so as to meet changing users’ counting conditions/requirements
  • Possibility to accommodate other ET methods for efficiency calculations

Work on further Angle improvements and upgrading continues – towards meeting spectrometrists’ needs and requirements.

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