Thermal neutron guide H22
Thermal D2O moderator


Height (mm) 200 (96.8m)
50 (5m)
Width (mm) 30
Total length [2] (m) 101.8
Curvature radius (main part) (m) -29700
Material Borkron/
Mixed Borkron-Borofloat/
Coating [3] m=2
Date of first commissioning 1972
Date of last major upgrade 2003-2006: replacement of the optical part before SALSA
Manufacturer (optical part) S-DH / SN / CILAS
Initial capture neutron flux at 58.6 MW (x1010 n/cm2/s) 0.185 [5]
0.113 [5]
Capture neutron flux June 2006 at 58.6 MW (x1010 n/cm2/s) 0.506
Instruments / Comments D1B


[1] Guide length from the rear plate ( 5.9 m de la source) to first instrument / first bifurcation.

[2] Guide length from the rear plate ( 5.9 m from source) to last instrument.

[3] Coating out of pile part. m=1 natural nickel ; m=1.2 58Ni ; m=2/m=3 Ti-Ni supermirror.

[4] In-pile optical part installed by Swiss Neutronics for all the guides H1 and H2 in 2006.

[5] Linearily scaled flux to 58.3 MW (most of the time the starting value is 57 MW).