BNMR-Oxford

4inch (101.7mm) UHV warm bore superconducting solenoid manufactured by Oxford Instruments (OI Project #01247). Maximum field 9T (at maximum current 89.534 A). Homogeneity over central 10x10mm : 20ppm radial, 3ppm axial, drift <0.1ppm/hr. This magnet is normally operated in persistent mode with an Oxford IPS120 magnet power supply via CAMP slow controls. This magnet has 10 inch Conflat flanges on both ends and is integrated into the spectrometer vacuum system. Beta-NMR is equiped with a UHV cryostat for axial access only. Standard sample holders accept samples 8x10mm, 0.2 - 0.5 mm thick. Samples are introduced into UHV and cryostat via a load lock. DC magnetic field is normal to tha sample face; AC field in plane of sample face. Two detectors count beta decay events in forward and backward directions. DAQ allows CW and pulsed RF and beam. Typical Li-8 rates 1E6/s per detector at high field > 1T.