D10 with 12T, 15T
We present below the magnetic forces measured on D10 with the 12T asymmetric split-pair coil magnet of the CEA CRG team.
The measurements have been performed with the analyser in a fixed position (-50°) because it cannot be used above 8T. The goniometer was removed before the test and it is therefore assumed that it will be removed each time the 12T magnet is installed.
The curves show the evolution of the radial and axial magnetic forces for a detector at 150° (elastic mode). These forces remain well below the limits imposed by the CRG CEA team for that cryomagnet, even when the detector is placed at the worse position of 60°.
In conclusion, this magnet can be used up to the maximum field when the goniometer is dismounted.
We present below the magnetic forces measured on D10 with the 15T symmetric split-pair coil magnet 158OXHV26. The two positions considered are those for which the cryomagnet is the nearest to the neutron guide, i.e. for which the magnetic forces are maximum. These take-off angles are 105.7 and 130° for the Cu (200) and pyrolytic graphite monochromators.
With the goniometer of the sample shaft in place, the vertical magnetic forces are very strong essentially because of the presence of the magnetic materials of the X and Y translation tables. The measurements show that with the goniometer mounted, the maximum allowable field is 7T.
When the goniometer and the translation tables are removed, the vertical forces are reduced by a factor 5 but the horizontal force is multiplied by 2 at the same take-off. Below 105.7°, the magnet can be used up to the maximum field but when the maximum take-off angle of 130° is chosen the field must be limited to 14T.