Upgrades to the Polarized Neutron Reflectometer Asterix at LANSCE

Pynn, Roger

关键词: Polarized Neutrons;    Neutron Spin Echo;    Neutron Reflectometry;   

DOI  :  10.2172/1172630
RP-ID  :  DOE-INDIANA-0002012
PID  :  OSTI ID: 1172630

美国|英语

来源: SciTech Connect

【 摘 要 】

We have upgraded the polarized neutron reflectometer, Asterix, at the Lujan Neutron Scattering Center at Los Alamos for the benefit of the research communities that study magnetic and complex-fluid films, both of which play important roles in support of the DOE???s energy mission. The upgrades to the instrument include: ??? A secondary spectrometer that was integrated with a Huber sample goniometer purchased with other funds just prior to the start of our project. The secondary spectrometer provides a flexible length for the scattered flight path, includes a mechanism to select among 3 alternative polarization analyzers as well as a support for new neutron detectors. Also included is an optic rail for reproducible positioning of components for Spin Echo Scattering Angle Measurement (SESAME). The entire secondary spectrometer is now non-magnetic, as required for neutron Larmor labeling. ??? A broad-band neutron polarizer for the incident neutron beam based on the V geometry. ??? A wide-angle neutron polarization analyzer ??? A 2d position-sensitive neutron detector ??? Electromagnetic coils (Wollaston prisms) for SESAME plus the associated power supplies, cooling, safety systems and integration into the data acquisition system. The upgrades allowed a nearly effortless transition between configurations required to serve the polarized neutron reflectometry community, users of the 11 T cryomagnet and users of SESAME.