D3 - The Spin Polarised Hot Neutron Beam Facility
D3 - The Spin Polarised Hot Neutron Beam Facility
It is a very versatile diffractometer for magnetic structure analysis. It offers several set-ups:
- a high field set-up for 1D polarimetry up to 10 Tesla ;
- a zero-field set-up for spherical neutron polarimetry with CRYOPAD ;
- a non-polarized set-up for experiments requiring both short wavelengths and high magnetic fields.
Recently a "liquids setup" has been added, to use the polarised neutrons to measure separately (and subtract) the spin-incoherent background.
Applications
High field configuration
- Magnetic form factors (reflecting the state of the magnetic ions);
Magnetisation distributions
Zero-field configuration
- Non-collinear magnetic structures ;
Antiferromagnetic form factors ;
Spherical polarimetry
Liquids configuration
- Separation of coherent and spin-incoherent scattering in hydrogenous liquids
Non-polarized beam with high magnetic field
Instrument layout
The high-field option implement a 10 Tesla cryomagnet.
The low-field option implement a third-generation CRYOPAD (CRYOgenic Polarisation Analysis Device) for precision measurement of neutron spin rotations occurring in the scattering process.
High field setup
Here, D3 is equiped with a 10 Tesla cryomagnet with a wide opening angle and a lifting detector. The neutron beam is polarised vertically. Large portions of the reciprocal space can be explored due to the relatively short wavelengths.
Zero field setup
Here, D3 is equiped with CRYOPAD and a 3He spin filter (DECPOL). This makes it possible to monitor separately the polarisations of the incident and scattered beams, in 3 dimensions.