.. auto-generated by dev_tools.docs.nxdl from the NXDL source contributed_definitions/NXsource.nxdl.xml -- DO NOT EDIT

.. index::
    ! NXsource (base class)
    ! source (base class)
    see: source (base class); NXsource

.. _NXsource:

========
NXsource
========

**Status**:

  base class, extends :ref:`NXobject`

**Description**:

  The neutron or x-ray storage ring/facility.

**Symbols**:

  The symbols used in the schema to specify e.g. dimensions of arrays

  **nx**: Number of points in a spectrum

**Groups cited**:
  :ref:`NXdata`, :ref:`NXgeometry`, :ref:`NXnote`

.. index:: NXnote (base class); used in base class, NXdata (base class); used in base class, NXgeometry (base class); used in base class

**Structure**:

  .. _/NXsource@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.

  .. _/NXsource/distance-field:

  .. index:: distance (field)

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

    Effective distance from sample Distance as seen by radiation from sample. This
    number should be negative to signify that it is upstream of the sample.

  .. _/NXsource/name-field:

  .. index:: name (field)

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

    Name of source

    .. _/NXsource/name@short_name-attribute:

    .. index:: short_name (field attribute)

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

      short name for source, perhaps the acronym

  .. _/NXsource/type-field:

  .. index:: type (field)

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

    Type of radiation source (pick one from the enumerated list and spell exactly)

    Any of these values:

      * ``Spallation Neutron Source``

      * ``Pulsed Reactor Neutron Source``

      * ``Reactor Neutron Source``

      * ``Synchrotron X-ray Source``

      * ``Pulsed Muon Source``

      * ``Rotating Anode X-ray``

      * ``Fixed Tube X-ray``

      * ``UV Laser``

      * ``Free-Electron Laser``

      * ``Optical Laser``

      * ``Ion Source``

      * ``UV Plasma Source``

      * ``Metal Jet X-ray``

      * ``arc lamp``

      * ``halogen lamp``

      * ``LED``


  .. _/NXsource/probe-field:

  .. index:: probe (field)

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

    Type of radiation probe (pick one from the enumerated list and spell exactly)

    Any of these values:

      * ``neutron``

      * ``x-ray``

      * ``muon``

      * ``electron``

      * ``ultraviolet``

      * ``visible light``

      * ``positron``

      * ``proton``


  .. _/NXsource/power-field:

  .. index:: power (field)

  **power**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_POWER <NX_POWER>`}

    Source power

  .. _/NXsource/emittance_x-field:

  .. index:: emittance_x (field)

  **emittance_x**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_EMITTANCE <NX_EMITTANCE>`}

    Source emittance (nm-rad) in X (horizontal) direction.

  .. _/NXsource/emittance_y-field:

  .. index:: emittance_y (field)

  **emittance_y**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_EMITTANCE <NX_EMITTANCE>`}

    Source emittance (nm-rad) in Y (horizontal) direction.

  .. _/NXsource/sigma_x-field:

  .. index:: sigma_x (field)

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

    Particle beam size in x

  .. _/NXsource/sigma_y-field:

  .. index:: sigma_y (field)

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

    Particle beam size in y

  .. _/NXsource/flux-field:

  .. index:: flux (field)

  **flux**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_FLUX <NX_FLUX>`}

    Source intensity/area (example: s-1 cm-2)

  .. _/NXsource/energy-field:

  .. index:: energy (field)

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

    Source energy. For storage rings, this would be the particle beam energy. For
    X-ray tubes, this would be the excitation voltage.

  .. _/NXsource/current-field:

  .. index:: current (field)

  **current**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_CURRENT <NX_CURRENT>`}

    Accelerator, X-ray tube, or storage ring current

  .. _/NXsource/voltage-field:

  .. index:: voltage (field)

  **voltage**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_VOLTAGE <NX_VOLTAGE>`}

    Accelerator voltage

  .. _/NXsource/frequency-field:

  .. index:: frequency (field)

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

    Frequency of pulsed source

  .. _/NXsource/period-field:

  .. index:: period (field)

  **period**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_PERIOD <NX_PERIOD>`}

    Period of pulsed source

  .. _/NXsource/target_material-field:

  .. index:: target_material (field)

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

    Pulsed source target material or other material used to generate light, e.g. He,
    Ar gas for lasers, Xe or Hg/Cd vapor for arc lamps, etc.

    Any of these values:

      * ``Ta``

      * ``W``

      * ``depleted_U``

      * ``enriched_U``

      * ``Hg``

      * ``Pb``

      * ``C``

      * ``Ar``

      * ``He``

      * ``Xe``

      * ``Hg/Cd``

      * ``H``


  .. _/NXsource/number_of_bunches-field:

  .. index:: number_of_bunches (field)

  **number_of_bunches**: (optional) :ref:`NX_INT <NX_INT>`

    For storage rings, the number of bunches in use.

  .. _/NXsource/bunch_length-field:

  .. index:: bunch_length (field)

  **bunch_length**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_TIME <NX_TIME>`}

    For storage rings, temporal length of the bunch

  .. _/NXsource/bunch_distance-field:

  .. index:: bunch_distance (field)

  **bunch_distance**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_TIME <NX_TIME>`}

    For storage rings, time between bunches

  .. _/NXsource/pulse_width-field:

  .. index:: pulse_width (field)

  **pulse_width**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_TIME <NX_TIME>`}

    Temporal width of source pulse

  .. _/NXsource/mode-field:

  .. index:: mode (field)

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

    Source operating mode

    Any of these values:

      * ``Single Bunch``: For storage rings

      * ``Multi Bunch``: For storage rings


  .. _/NXsource/top_up-field:

  .. index:: top_up (field)

  **top_up**: (optional) :ref:`NX_BOOLEAN <NX_BOOLEAN>`

    Is the synchrotron operating in top_up mode?

  .. _/NXsource/last_fill-field:

  .. index:: last_fill (field)

  **last_fill**: (optional) :ref:`NX_NUMBER <NX_NUMBER>` {units=\ :ref:`NX_CURRENT <NX_CURRENT>`}

    For storage rings, the current at the end of the most recent injection.

    .. _/NXsource/last_fill@time-attribute:

    .. index:: time (field attribute)

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

      Date and time of the most recent injection.

  .. _/NXsource/photon_energy-field:

  .. index:: photon_energy (field)

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

    The center photon energy of the source, before it is monochromatized or
    converted

  .. _/NXsource/center_wavelength-field:

  .. index:: center_wavelength (field)

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

    The center wavelength of the source, before it is monochromatized or converted

  .. _/NXsource/pulse_energy-field:

  .. index:: pulse_energy (field)

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

    For pulsed sources, the energy of a single pulse

  .. _/NXsource/peak_power-field:

  .. index:: peak_power (field)

  **peak_power**: (optional) :ref:`NX_FLOAT <NX_FLOAT>` {units=\ :ref:`NX_POWER <NX_POWER>`}

    For pulsed sources, the pulse energy divided by the pulse duration

  .. _/NXsource/bunch_number_start-field:

  .. index:: bunch_number_start (field)

  **bunch_number_start**: (optional) :ref:`NX_INT <NX_INT>`

    Some facilities tag each bunch. First bunch of the  measurement

  .. _/NXsource/bunch_number_end-field:

  .. index:: bunch_number_end (field)

  **bunch_number_end**: (optional) :ref:`NX_INT <NX_INT>`

    Last bunch of the  measurement

  .. _/NXsource/notes-group:

  **notes**: (optional) :ref:`NXnote`

    Any source/facility related messages/events that occurred during the experiment

  .. _/NXsource/bunch_pattern-group:

  **bunch_pattern**: (optional) :ref:`NXdata`

    For storage rings, description of the bunch pattern. This is useful to describe
    irregular bunch patterns.

    .. _/NXsource/bunch_pattern/title-field:

    .. index:: title (field)

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

      name of the bunch pattern

  .. _/NXsource/pulse_shape-group:

  **pulse_shape**: (optional) :ref:`NXdata`

    Source pulse shape

  .. _/NXsource/geometry-group:

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

    'Engineering' location of source

  .. _/NXsource/distribution-group:

  **distribution**: (optional) :ref:`NXdata`

    The wavelength or energy distribution of the source


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

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


* :ref:`/NXsource/bunch_distance-field </NXsource/bunch_distance-field>`
* :ref:`/NXsource/bunch_length-field </NXsource/bunch_length-field>`
* :ref:`/NXsource/bunch_number_end-field </NXsource/bunch_number_end-field>`
* :ref:`/NXsource/bunch_number_start-field </NXsource/bunch_number_start-field>`
* :ref:`/NXsource/bunch_pattern-group </NXsource/bunch_pattern-group>`
* :ref:`/NXsource/bunch_pattern/title-field </NXsource/bunch_pattern/title-field>`
* :ref:`/NXsource/center_wavelength-field </NXsource/center_wavelength-field>`
* :ref:`/NXsource/current-field </NXsource/current-field>`
* :ref:`/NXsource/distance-field </NXsource/distance-field>`
* :ref:`/NXsource/distribution-group </NXsource/distribution-group>`
* :ref:`/NXsource/emittance_x-field </NXsource/emittance_x-field>`
* :ref:`/NXsource/emittance_y-field </NXsource/emittance_y-field>`
* :ref:`/NXsource/energy-field </NXsource/energy-field>`
* :ref:`/NXsource/flux-field </NXsource/flux-field>`
* :ref:`/NXsource/frequency-field </NXsource/frequency-field>`
* :ref:`/NXsource/geometry-group </NXsource/geometry-group>`
* :ref:`/NXsource/last_fill-field </NXsource/last_fill-field>`
* :ref:`/NXsource/last_fill@time-attribute </NXsource/last_fill@time-attribute>`
* :ref:`/NXsource/mode-field </NXsource/mode-field>`
* :ref:`/NXsource/name-field </NXsource/name-field>`
* :ref:`/NXsource/name@short_name-attribute </NXsource/name@short_name-attribute>`
* :ref:`/NXsource/notes-group </NXsource/notes-group>`
* :ref:`/NXsource/number_of_bunches-field </NXsource/number_of_bunches-field>`
* :ref:`/NXsource/peak_power-field </NXsource/peak_power-field>`
* :ref:`/NXsource/period-field </NXsource/period-field>`
* :ref:`/NXsource/photon_energy-field </NXsource/photon_energy-field>`
* :ref:`/NXsource/power-field </NXsource/power-field>`
* :ref:`/NXsource/probe-field </NXsource/probe-field>`
* :ref:`/NXsource/pulse_energy-field </NXsource/pulse_energy-field>`
* :ref:`/NXsource/pulse_shape-group </NXsource/pulse_shape-group>`
* :ref:`/NXsource/pulse_width-field </NXsource/pulse_width-field>`
* :ref:`/NXsource/sigma_x-field </NXsource/sigma_x-field>`
* :ref:`/NXsource/sigma_y-field </NXsource/sigma_y-field>`
* :ref:`/NXsource/target_material-field </NXsource/target_material-field>`
* :ref:`/NXsource/top_up-field </NXsource/top_up-field>`
* :ref:`/NXsource/type-field </NXsource/type-field>`
* :ref:`/NXsource/voltage-field </NXsource/voltage-field>`
* :ref:`/NXsource@default-attribute </NXsource@default-attribute>`

**NXDL Source**:
  https://github.com/nexusformat/definitions/blob/main/contributed_definitions/NXsource.nxdl.xml