.. auto-generated by script ../../../../utils/nxdl2rst.py from the NXDL source NXfermi_chopper.nxdl.xml

.. index::
    ! NXfermi_chopper (base class)
    ! fermi_chopper (base class)
    see: fermi_chopper (base class); NXfermi_chopper

.. _NXfermi_chopper:

===============
NXfermi_chopper
===============

**Status**:

  base class, extends :ref:`NXobject`

**Description**:

  A Fermi chopper, possibly with curved slits.

**Symbols**:

  No symbol table

**Groups cited**:
  :ref:`NXgeometry`

.. index:: NXgeometry (base class); used in base class

**Structure**:

  .. _/NXfermi_chopper@default-attribute:

  .. index:: default (file attribute)

  **@default**: (optional) :ref:`NX_CHAR <NX_CHAR>`

    .. index:: plotting

    Declares which child group contains a path leading 
    to a :ref:`NXdata` group.

    It is recommended (as of NIAC2014) to use this attribute
    to help define the path to the default dataset to be plotted.
    See https://www.nexusformat.org/2014_How_to_find_default_data.html
    for a summary of the discussion.

  .. _/NXfermi_chopper/type-field:

  .. index:: type (field)

  **type**: (optional) :ref:`NX_CHAR <NX_CHAR>`

    Fermi chopper type

  .. _/NXfermi_chopper/rotation_speed-field:

  .. index:: rotation_speed (field)

  **rotation_speed**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_FREQUENCY <NX_FREQUENCY>`}

    chopper rotation speed

  .. _/NXfermi_chopper/radius-field:

  .. index:: radius (field)

  **radius**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_LENGTH <NX_LENGTH>`}

    radius of chopper

  .. _/NXfermi_chopper/slit-field:

  .. index:: slit (field)

  **slit**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_LENGTH <NX_LENGTH>`}

    width of an individual slit

  .. _/NXfermi_chopper/r_slit-field:

  .. index:: r_slit (field)

  **r_slit**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_LENGTH <NX_LENGTH>`}

    radius of curvature of slits

  .. _/NXfermi_chopper/number-field:

  .. index:: number (field)

  **number**: (optional) :ref:`NX_INT <NX_INT>` {units=\ :ref:`NX_UNITLESS <NX_UNITLESS>`}

    number of slits

  .. _/NXfermi_chopper/height-field:

  .. index:: height (field)

  **height**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_LENGTH <NX_LENGTH>`}

    input beam height

  .. _/NXfermi_chopper/width-field:

  .. index:: width (field)

  **width**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_LENGTH <NX_LENGTH>`}

    input beam width

  .. _/NXfermi_chopper/distance-field:

  .. index:: distance (field)

  **distance**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_LENGTH <NX_LENGTH>`}

    distance

  .. _/NXfermi_chopper/wavelength-field:

  .. index:: wavelength (field)

  **wavelength**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_WAVELENGTH <NX_WAVELENGTH>`}

    Wavelength transmitted by chopper

  .. _/NXfermi_chopper/energy-field:

  .. index:: energy (field)

  **energy**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_ENERGY <NX_ENERGY>`}

    energy selected

  .. _/NXfermi_chopper/absorbing_material-field:

  .. index:: absorbing_material (field)

  **absorbing_material**: (optional) :ref:`NX_CHAR <NX_CHAR>`

    absorbing material

  .. _/NXfermi_chopper/transmitting_material-field:

  .. index:: transmitting_material (field)

  **transmitting_material**: (optional) :ref:`NX_CHAR <NX_CHAR>`

    transmitting material

  .. _/NXfermi_chopper/GEOMETRY-group:

  **GEOMETRY**: (optional) :ref:`NXgeometry`

    geometry of the fermi chopper


Hypertext Anchors
-----------------

Table of hypertext anchors for all groups, fields,
attributes, and links defined in this class.


================================================================================================== ==================================================================================================
documentation (reST source) anchor                                                                 web page (HTML) anchor                                                                            
================================================================================================== ==================================================================================================
:ref:`/NXfermi_chopper/absorbing_material-field </NXfermi_chopper/absorbing_material-field>`       :ref:`#nxfermi-chopper-absorbing-material-field </NXfermi_chopper/absorbing_material-field>`      
:ref:`/NXfermi_chopper/distance-field </NXfermi_chopper/distance-field>`                           :ref:`#nxfermi-chopper-distance-field </NXfermi_chopper/distance-field>`                          
:ref:`/NXfermi_chopper/energy-field </NXfermi_chopper/energy-field>`                               :ref:`#nxfermi-chopper-energy-field </NXfermi_chopper/energy-field>`                              
:ref:`/NXfermi_chopper/GEOMETRY-group </NXfermi_chopper/GEOMETRY-group>`                           :ref:`#nxfermi-chopper-geometry-group </NXfermi_chopper/GEOMETRY-group>`                          
:ref:`/NXfermi_chopper/height-field </NXfermi_chopper/height-field>`                               :ref:`#nxfermi-chopper-height-field </NXfermi_chopper/height-field>`                              
:ref:`/NXfermi_chopper/number-field </NXfermi_chopper/number-field>`                               :ref:`#nxfermi-chopper-number-field </NXfermi_chopper/number-field>`                              
:ref:`/NXfermi_chopper/r_slit-field </NXfermi_chopper/r_slit-field>`                               :ref:`#nxfermi-chopper-r-slit-field </NXfermi_chopper/r_slit-field>`                              
:ref:`/NXfermi_chopper/radius-field </NXfermi_chopper/radius-field>`                               :ref:`#nxfermi-chopper-radius-field </NXfermi_chopper/radius-field>`                              
:ref:`/NXfermi_chopper/rotation_speed-field </NXfermi_chopper/rotation_speed-field>`               :ref:`#nxfermi-chopper-rotation-speed-field </NXfermi_chopper/rotation_speed-field>`              
:ref:`/NXfermi_chopper/slit-field </NXfermi_chopper/slit-field>`                                   :ref:`#nxfermi-chopper-slit-field </NXfermi_chopper/slit-field>`                                  
:ref:`/NXfermi_chopper/transmitting_material-field </NXfermi_chopper/transmitting_material-field>` :ref:`#nxfermi-chopper-transmitting-material-field </NXfermi_chopper/transmitting_material-field>`
:ref:`/NXfermi_chopper/type-field </NXfermi_chopper/type-field>`                                   :ref:`#nxfermi-chopper-type-field </NXfermi_chopper/type-field>`                                  
:ref:`/NXfermi_chopper/wavelength-field </NXfermi_chopper/wavelength-field>`                       :ref:`#nxfermi-chopper-wavelength-field </NXfermi_chopper/wavelength-field>`                      
:ref:`/NXfermi_chopper/width-field </NXfermi_chopper/width-field>`                                 :ref:`#nxfermi-chopper-width-field </NXfermi_chopper/width-field>`                                
:ref:`/NXfermi_chopper@default-attribute </NXfermi_chopper@default-attribute>`                     :ref:`#nxfermi-chopper-default-attribute </NXfermi_chopper@default-attribute>`                    
================================================================================================== ==================================================================================================


**NXDL Source**:
  https://github.com/FAIRmat-Experimental/nexus_definitions/tree/fairmat/base_classes/NXfermi_chopper.nxdl.xml