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Output data CR-39

The output file contains the Following information:

1. Date and time of the scan

2. Code of dosimeter

3. Track density (Tracks/cm²)

4. Poisson uncertainty of track density

5. Area covered by the tracks (cm²)

6. Test result of reduced CHI²

7. Threshold tracks area (pixels²)

8. Exposure to radon

9. Uncertainty in exposure to radon

10. Notice of error in reading the code

11. Error wro
ng focus alert


Special note:

Point 5 means that the sum of the areas of all tracks on the detector is done and is a key parameter for the calculation of exposure to radon.

The point 6 is the test result of the reduced CHI² calculated on the number of acquisitions. It is defined as the ratio of the estimated variance and the mean estimate of the number of tracks counted in each frame analyzed: the traces should follow a Poisson distribution, if not it means that the scan may have been subject to a problem (e.g a detector damaged or surface contaminated by dust particles).

For example: in the case of 100 acquisitions, we have that 0.778 <CHI2 <1.244 with a probability of 90%.

Point 7 sets out the threshold area applied for acceptance of the tracks. This is calculated at the end of the scan for each detector on the basis of the distribution of the track areas. This analysis is particularly useful in the case of having very old CR39 detectors in which there is a tendency for a decrease in the medium track area.

Reserved Area