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Detailed Specifications

Monochromators:

  1. Pyrolytic Graphite, 4.0" high and 3.0" (75 mm) long, 30‘ mosaic, vertically focused to optimize 14.7 meV neutrons. Reflection geometry.
    Plots Information Page
  2. Heusler Alloy, 4.0" high and 3.0" long, 18’ mosaic, vertically focused to optimize 14.7 meV neutrons.Reflection geometry.

Collimation:

In-pile Rotating Shutter either 21' or 60' (FWHM)
Monochromator to Sample Brass, 2.5 x 1.5” with Cd coated brass blades
Sample to Analyzer Brass, 2 x 1.5" with Cd coated brass blades to 5'
Detector Steel Fixed at 40' or 20' (separate collimators)

For the Monochromator-to-sample and Sample-to-analyzer collimators, there are separate collimators for 5' and 10': Do Not Remove the Blades in these Collimators under any circumstances!!! There is also a 20' collimator for each position, and the blades can be removed from these to achieve coarser collimations when needed.

Analyzer:

  1. Flat Pyrolytic Graphite
  2. Flat Heusler Alloy in magnet assembly
  3. 2 Θ c supermirror polarizer in Söller slit arrangement
    supermirror polarizer
    Click for larger image


  4. Horizontally Focussed PG optimized for 14.7 meV (Intensity gain ~2.5)
    Horizontally Focussed PG optimized
    Click for larger image

Filters:

Source Beam:

  1. Cold (liquid nitrogen) polycrystal beryllium block, with approximate dimensions of 3 x 3 x 6 in 3, mounted on an elevator and remotely operated.
  2. PG filter, with dimensions of 2.5 x 2 x 2 in3, mounted in an elevator and remotely operated. The tilt and rotation of the filter may also be manually adjusted remotely.
Scattered Beam: PG filter

Motors and Ranges:

Motors 1 & 2 are computer driven in a q M:2 Θ M motion. The range of the monochromator drum 2 qM is from 21 º to 77º.

Motor 3 is the sample angle, 0-360º

Motor 4 is the scattering angle, which can go from -9-120º

Motor 5 is the analyzer, 0-360º

Motor 6 is the detector angle, which can go from -1-145º (Note: make sure the detector is not obstructed by extra shielding inside)

Motors 7 and 8 are the sample goniometer tilts ( ±22º )

Motors 9 and 10 are the sample goniometer translations (± 20 mm)

Motor 11 is the monochromator tilt,
Motor 12 is the monochromator translation

Motor 13 is the monochromator height (to switch from PG to Heusler)

Motors 15 and 16 are for the beam-limiter slits before the sample

Motors 17 and 18 are for the beam-limiter slits after the sample



General Specifications  •   Detailed Specifications   •   Operational Notes   •   Polarized Beam Operation



Last modified 12-November-2003 by website owner: NCNR (attn: Jeff Lynn)