| Airborne spectrometer |
| Detector size | 4x4x16 inch |
| Volume | 4 litre |
| Weight (ex. housing) | 20kgs |
| Material | CsI(Na) |
| MCA channels | 512 |
| Base | 14 pins |
| I/O | USB |
| Transmission | 10Hz |
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| Environmental correction unit |
| Air pressure meter | 1 hz sampling rate |
| Air temperature meter | 1 hz sampling rate |
| Elevation meter | RA3000 from Freeflight |
| Positioning system | dGPS system |
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| Logging software |
| Quality control | On-line inspection of the gamma ray spectra;
10Hz display and storage of data for post-processing;
Display and recording of dGPS positions |
| Recording of environmental factors | Elevation
Temperature
Pressure |
| Failure detection | Detector breakdown
GPS loss of data |
| Synchronisation and storage | Data storage for off-line correction and analysis
GPS, nuclear and environmental data in Excel format
Output for mission planning, x,y, total gamma activity (uncorrected for environment) |
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| Off-line correction and analysis software |
| Gain stabilization | The system uses sophisticated automatic gain stabilization (AGS) algorithms. Using our AGS, the system is stabilized for temperature drifts and other electronics-induced spectral drifting. (c.f. Hendriks, 2001). The system therefore does not need a built-in source or other hardware to stabilize the system. |
| Background correction | In airborne surveying, cosmic and Radon background radiation needs to be accounted for. In Medusa post processing software, such background corrections are accounted for, via means of enhanced spectral analysis (c.f. Minty 1998). These backgrounds will be removed during the post-processing stage. |
| Spectral analysis Patented | data analysis algorithms use the full spectral information in determining the nuclide concentrations (Hendriks, 2001) |
| Calibration | The system is calibrated by means of Monte Carlo modelling and measurements in the Medusa calibration facility |
| Data gridding | To account for the inherent statistical fluctuations in the data, the data is smoothed and interpolated by using enhanced Kriging interpolation. this interpolation method allows to specify the statistical uncertainty in data analysis |
| Output | Ground concentrations of U, Th, K in Bq/kg |
