4.3.1.33. NXmonochromator¶
Status:
base class, extends NXobject
Description:
A wavelength defining device.
This is a base class for everything which selects a wavelength or energy, be it a monochromator crystal, a velocity selector, an undulator or whatever.
The expected units are:
wavelength: angstrom
energy: eV
Symbols:
No symbol table
- Groups cited:
NXcrystal, NXdata, NXgeometry, NXgrating, NXoff_geometry, NXtransformations, NXvelocity_selector
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.
wavelength: (optional) NX_FLOAT {units=NX_WAVELENGTH}
wavelength selected
wavelength_error: (optional) NX_FLOAT {units=NX_WAVELENGTH}
DEPRECATED: see https://github.com/nexusformat/definitions/issues/820
wavelength standard deviation
wavelength_errors: (optional) NX_FLOAT {units=NX_WAVELENGTH}
wavelength standard deviation
energy: (optional) NX_FLOAT {units=NX_ENERGY}
energy selected
energy_error: (optional) NX_FLOAT {units=NX_ENERGY}
DEPRECATED: see https://github.com/nexusformat/definitions/issues/820
energy standard deviation
energy_errors: (optional) NX_FLOAT {units=NX_ENERGY}
energy standard deviation
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.
distribution: (optional) NXdata
geometry: (optional) NXgeometry
DEPRECATED: Use the field depends_on and NXtransformations to position the monochromator and NXoff_geometry to describe its shape instead
OFF_GEOMETRY: (optional) NXoff_geometry
This group describes the shape of the beam line component
CRYSTAL: (optional) NXcrystal
Use as many crystals as necessary to describe
VELOCITY_SELECTOR: (optional) NXvelocity_selector
GRATING: (optional) NXgrating
For diffraction grating based monochromators
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.