SwissNeutronics AG - Bruehlstrasse 28 - CH-5313 Klingnau - Switzerland - phone: +4156 245 02 02 - tech@swissneutronics.ch

Heusler monochromator

SwissNeutronics has developed a dedicated design for the mechanism for focusing Heusler monochromators/analysers. The key elements are individual yokes for each row/column providing a homogeneous, high magnetic field to magnetize the Heusler crystals. Thus a very high polarization is achieved. Moreover, the arrangement of the Heusler crystals is optimized considering neutron rocking scans and variations of the size of the crystals.

 

 

Particular features are:

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High precision:

 

< ≈0.05° (RMS, absolute)

< ±0.02° (repeatability)

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Magnetic field > 1.4 kG

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Measured neutron polarisation P > 94%

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Combined with goniometer stage

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Fully equipped with stepper motor, encoder/resolver, home/limit switches

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Individual magnetic yokes for every crystal row with optimized magnetic yoke design (compact size)

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Additional features: shielding elements, integrated guide field, etc.

2d focusing Heusler analyzer - FLEX @ HZB (2013)

  • Analyser array - variable horizontal & fixed vertical focusing

     

    		Crystal:
    Crystal dimensions:
    Reflecting area:
    Number of rows:
    Number of columns:
    Gaps between rows:    		Heusler
    15 mm (w) x 40 mm (h) x 5 mm (t)
    233 mm (w) x 116.5 mm (h)
    1 (3 Heusler per row)
    1
    5
    0.6 mm
    Focusing features

     

    		Focusing direction:
    Horizontal focusing range:
    Vertical focusing:
    Accuracy:
    Repeatability:    		horizontal (variable) & vertical (fixed)
    flat -> Rh = 1250 mm
    Rv = 770 mm
    < 0.026° RMS (measured)
    < ±0.01° (measured)
    Actuation components

     

    		Motor:
    Rotary encoder:
    Switches:    		stepper motor
    resolver
    2 limit switches
    Specials

     

    		Compact design

1d focusing Heusler monochromator - HYSPEC @ SNS (2010)

  • Monochromator array

     

    		Crystal:
    Crystal dimensions:
    Reflecting area:
    Number of rows:
    Number of columns:
    Gaps between rows:    		Heusler
    50 mm (w) x 15 mm (h) x 6 mm (t)
    150 mm (w) x 207 mm (h)
    13
    1 (3 Heusler per column)
    1 mm
    Focusing features

     

    		Focusing direction:
    Vertical Focusing range:
    Accuracy:
    Repeatability:    		vertical
    flat -> Rv = 600 mm
    < 0.04° RMS (measured)
    < ±0.02° (measured)
    Actuation components

     

    		Motor:
    Rotary encoder:
    Switches:    		stepper motor
    encoder
    2 limit switches
    Specials

     

    		Integrated into exchange mechanism (vertical lift)

1d focusing Heusler monochromator - @ HFIR (2008)

  • Monochromator array

     

    		Crystal:
    Crystal dimensions:
    Reflecting area:
    Number of rows:
    Number of columns:
    Gaps between rows:    		Heusler
    75 mm (w) x 15 mm (h) x 5 mm (t)
    170 mm (w) x 150 mm (h)
    11
    1 (2 Heusler per row)
    0.5 mm
    Focusing features

     

    		Focusing direction:
    Vertical focusing range:    		vertical
    0.42m < Rv < ∞
    Actuation components

     

    		Motor:
    Rotary encoder:
    Switches:    		stepper motor
    encoder
    2 limit switches