TRIPLE AXIS

NSF: Triple Axis Spectrometer (TAS)

The schematic shown above illustrates the use of NSFs on the BT-7, triple axis spectrometer. In this configuration, a NSF is used as both the polarizer and the analyzer. On the polarizer side (upstream of sample), a ³He cell is located inside a mumetal shielded box or "MAGIC" Box or a mumetal shielded solenoid. On the analyzer side (downstream of sample), a ³He cell is located inside a mumetal shielded solenoid. The polarization of each ³He cell is monitored using in-situ NMR. All Triple Axis publication can be found here.

PDF slide provided for presentation use: Neutron Spin Filters on BT-7

Specifications or NSF on BT-7 Triple Axis

Credit: Wangchun Chen

3He cell as polarizer and analyzer 3He polarization flipping capability Elastic and inelastic measurements Sample field magnitude: H ~ 10G P \({\parallel}\) Q or P \({\perp}\) Q Superconducting Magnet field: up to 2 T Four cross-section polarization efficiency correction both horizontal and vertical field 3He transmission: \({\leq}\) 50% (for desired spin state) Flipping ratio: \({\leq}\) 60