NXvelocity_selector¶
Status:
base class, extends NXobject
Description:
A neutron velocity selector
Symbols:
No symbol table
- Groups cited:
Structure:
@default: (optional) NX_CHAR
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
velocity selector type
rotation_speed: (optional) NX_FLOAT {units=NX_FREQUENCY}
velocity selector rotation speed
radius: (optional) NX_FLOAT {units=NX_LENGTH}
radius at beam centre
spwidth: (optional) NX_FLOAT {units=NX_LENGTH}
spoke width at beam centre
length: (optional) NX_FLOAT {units=NX_LENGTH}
rotor length
num: (optional) NX_INT {units=NX_UNITLESS}
number of spokes/lamella
twist: (optional) NX_FLOAT {units=NX_ANGLE}
twist angle along axis
table: (optional) NX_FLOAT {units=NX_ANGLE}
offset vertical angle
height: (optional) NX_FLOAT {units=NX_LENGTH}
input beam height
width: (optional) NX_FLOAT {units=NX_LENGTH}
input beam width
wavelength: (optional) NX_FLOAT {units=NX_WAVELENGTH}
wavelength
wavelength_spread: (optional) NX_FLOAT {units=NX_WAVELENGTH}
deviation FWHM /Wavelength
depends_on: (optional) NX_CHAR
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 velocity selector and NXoff_geometry to describe its shape instead
OFF_GEOMETRY: (optional) NXoff_geometry
This group describes the shape of the beam line component
TRANSFORMATIONS: (optional) NXtransformations
This is the group recommended for holding the chain of translation and rotation operations necessary to position the component within the instrument. The dependency chain may however traverse similar groups in other component groups.
Hypertext Anchors¶
List of hypertext anchors for all groups, fields, attributes, and links defined in this class.
