base class, extends NXobject


A Fermi chopper, possibly with curved slits.


No symbol table

Groups cited:

NXgeometry, NXoff_geometry, NXtransformations


@default: (optional) NX_CHAR

Declares which child group contains a path leading ...

Declares which child group contains a path leading to a 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.

type: (optional) NX_CHAR

Fermi chopper type

rotation_speed: (optional) NX_FLOAT {units=NX_FREQUENCY}

chopper rotation speed

radius: (optional) NX_FLOAT {units=NX_LENGTH}

radius of chopper

slit: (optional) NX_FLOAT {units=NX_LENGTH}

width of an individual slit

r_slit: (optional) NX_FLOAT {units=NX_LENGTH}

radius of curvature of slits

number: (optional) NX_INT {units=NX_UNITLESS}

number of slits

height: (optional) NX_FLOAT {units=NX_LENGTH}

input beam height

width: (optional) NX_FLOAT {units=NX_LENGTH}

input beam width

distance: (optional) NX_FLOAT {units=NX_LENGTH}

distance. Note, it is recommended to use NXtransformations instead.

wavelength: (optional) NX_FLOAT {units=NX_WAVELENGTH}

Wavelength transmitted by chopper

energy: (optional) NX_FLOAT {units=NX_ENERGY}

energy selected

absorbing_material: (optional) NX_CHAR

absorbing material

transmitting_material: (optional) NX_CHAR

transmitting material

depends_on: (optional) NX_CHAR

NeXus positions components by applying a set of translations and rotations ...

NeXus positions components by applying a set of translations and rotations to apply to the component starting from 0, 0, 0. The order of these operations is critical and forms what NeXus calls a dependency chain. The depends_on field defines the path to the top most operation of the dependency chain or the string “.” if located in the origin. Usually these operations are stored in a NXtransformations group. But NeXus allows them to be stored anywhere.

GEOMETRY: (optional) NXgeometry

DEPRECATED: Use the field depends_on and NXtransformations to position the chopper and NXoff_geometry to describe its shape instead

geometry of the fermi chopper

OFF_GEOMETRY: (optional) NXoff_geometry

This group describes the shape of the beam line component

TRANSFORMATIONS: (optional) NXtransformations

Hypertext Anchors

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

NXDL Source: