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| === Proposed Measurement Program === | | === Proposed Measurement Program === |
| + | The following procedure uses as a unit of radiation dose the '''rem''' based on the neutron dosimeter used in [http://www.jlab.org/Hall-D/software/wiki/index.php?title=SiPM_Radiation_Hardness_Test&redirect=no the study by Y. Qiang et.al. referenced above]. |
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− | # Irradiation with about 40 rem over the course of a few days (source strength selected appropriately) with ''full measurement'' performed periodically. | + | # Irradiation with monitoring until the dark rate in the SiPM has increased by a factor 2 over the initial conditions, then allow the SiPM to self-anneal and monitor its recovery. |
− | # Relaxation time (of duration determined by the apparent healing rate) with ''full measurement'' performed periodically. | + | # Monitoring will consist of ''full measurements'' (see below) taken at several points during irradiation, and periodically during annealing. |
− | # Repetition of 1. and 2. as desired to determine the recovery extent | + | # The initial period between measurements while irradiating should be 1 rem, to be adjusted after a trend is observed. |
− | # Proceed with a longer irradiation period until significant curvature is seen in the change of the performance parameters in order to measure the decay function (e.g. two exponential?) | + | # The initial period between measurements while annealing should be one day, to be adjusted after a relaxation time is observed. |
| + | # Once the data up to factor-2 dark rate increase and subsequent annealing have been analyzed, proceed with a longer irradiation period until significant curvature is seen in the dark rate vs. dose curve. then repeat the annealing measurements to compare with the initial relaxation rates. |
| # Irradiate the unit for a much longer duration - until some saturation of the performance parameters is seen. This will help determine the offset in the model of the deterioration of performance parameters. | | # Irradiate the unit for a much longer duration - until some saturation of the performance parameters is seen. This will help determine the offset in the model of the deterioration of performance parameters. |
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