Neutron irradiation facilities
The HOR has various neutron irradiation facilities installed.
Most often used are the pneumatic systems (BP2 through BP4) for irradiations of a few minutes up to 10 hours. The similar near-core FlexBeFa offers a much lower gamma dose rate. For very short irradiations, as applied in activation analysis, the SBP pneumatic system offers fast transit times. For longer irradiations, the in-core BigBeBe and SmallBeBe are available. And finally, the purely thermal BISNIS facility in the thermal column of the reactor allows for long irradiations of large objects.
| thermal flux | epithermal flux | fast flux | fast flux | fast flux | max time | gamma dose rate | max sample dimensions |
0 - 0.5 eV | 0.5 eV - 1 keV | 1 keV - 1MeV | 1 MeV- 10MeV | 1 keV - 10 MeV | kGy per hour | |||
BP2-4 | 5x1012 | 1x1012 |
| 3x1011 | 10 h | 220 | 20mm dia x 100mm height | |
SBP | 1.5x1013 | 6x1012 |
| 2x1012 | 10 m | - | 9mm dia x 9mm height | |
FlexBeFa | 5x1012 | 1x1011 |
| 3x1011 | 10 h | -40 | 9mm dia x 9mm height | |
BigBeBe | 2.5x1013 | 2.5x1013 | 1.5x1013 | 5.9x1012 | 2.1x1013 | no limit | 1750 | 31mm dia x 70mm height |
SmallBeBe | 3.5x1013 | 2.5x1013 | 2x1013 | 1.5x1013 | 3.5x1013 | no limit | 3200 | 9 mm dia x 75mm height |
BISNIS | 8x108 | 0 | 0 |
|
| no limit | 0.007 | 140 mm dia x 1000 mm height |
All neutron fluxes are given in cm-2s-1. The thermal flux is defined as the integral from 0 to 0.5 eV, the epithermal flux is defined as the integral from 0.5 eV to 1 keV, and the fast flux as the integral from 1 keV to 20 MeV. The epithermal flux at 1 eV as commonly used in INAA conventions can be estimated from the one given above by dividing by 15.