A description is given of the prototype polarized neutron reflectometer installed at the intense pulsed neutron source. This instrument is designed for determining the magnetic depth profiles near the surfaces of ferromagnets and superconductors, by measuring the spin-dependent reflectivities of a well-collimated (0.01°) beam of cold neutrons from surfaces of a few cm2. Magnetic profiles can be determined with the spatial resolution of 40 Å, over thicknesses up to 5000 Å. Variations of the magnetic flux of the order of 10−5 G cm2 can be detected.

Two time-of-flight powder diffractometers have operated at the Intense Pulsed Neutron Source (IPNS) since August 1981. These instruments use dedicated microcomputers to focus time-of-flight events so that data from different detectors can be summed into a single histogram. Thus, large multidetector arrays can be employed at any scattering angle from 12 to 157 °. This design permits data to be collected over a uniquely wide range of d spacings while maintaining high resolution and count rates. The performance of the two instruments is evaluated by analyzing data from a standard A1203 sample by the Rietveld method. These instruments provide the capability for moderate-to high-resolution measurements with the duration of a typical run being a few hours.

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We have designed and constructed a stable isotope ratiometer-multipie ion detector unit, which can drive existing gas chromatograph-quadrupole or magnetic sector mass spectrometers to monitor up to six ions in turn. Each of the three pairs of ions can be selected for quantitation; thus three different or successive components can be analyzed in a single gas-chromatographic run. A background subtraction option permits the ion intensity in the absence of sample to be subtracted automatically during sample measurement. Displays of accumulated counts and isotope ratio are updated twice per second during the measurement and can be printed out at its conclusion. All six ions can be monitored in the analog mode by parallel outputs to a multipen recorder. Experience gained in the construction of this prototype indicates that such units could be commercially available for $10 000, or about a third to a sixth of the cost of even an inexpensive computer system.

The submitted manuscript has been authored by a contractor of the U. S. Government under contract No. W-31-109-ENG-38-Accordingly, the U. S. Government retains a nonexclusive, royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for U. S. Government purposes.