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.

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