Search results for "Mechanical compression"

showing 2 items of 2 documents

He-3 spin filter for neutrons

2005

The strongly spin-dependent absorption of neutrons in nuclear spin-polarized (3)He opens up the possibility of polarizing neutrons from reactors and spallation sources over the full kinematical range of cold, thermal and hot neutrons. This paper gives a report on the neutron spin filter (NSF) development program at Mainz. The polarization technique is based on direct optical pumping of metastable (3)He atoms combined with a polarization preserving mechanical compression of the gas up to a pressure of several bar, necessary to run a NSF. The concept of a remote type of operation using detachable NSF cells is presented which requires long nuclear spin relaxation times of order 100 hours. A sh…

Optical pumpingNuclear physicsPhysicsMetastabilityNuclear TheoryMechanical compressionThermalGeneral EngineeringNeutronSpallationSpin filterNuclear ExperimentPolarization (waves)Journal of Research of the National Institute of Standards and Technology
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Interdisciplinary experiments with polarized 3He

1998

Abstract Optical pumping of metastable 3 He atoms is a very efficient method to produce large quantities of nuclear spin-polarized 3 He. Recent developments in mechanical compression of the gas, its storage and transport allow for its flexible use in different fields of physics and applied science. Among these are (1) scattering experiments of polarized beams from polarized 3 He-targets, (2) 3 He as neutron spin filter to polarize neutron beams at research reactors, and (3) polarized 3 He gas inhaled into the lungs to perform magnetic resonance imaging. The paper discusses the different topics along with results obtained in a first round of experiments.

PhysicsOptical pumpingNuclear and High Energy PhysicsNeutron magnetic momentSpin polarizationScatteringMetastabilityMechanical compressionNeutronNeutron scatteringAtomic physicsInstrumentationNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
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