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

.. index::
    ! NXxas_tey (application definition)
    ! xas_tey (application definition)
    see: xas_tey (application definition); NXxas_tey

.. _NXxas_tey:

=========
NXxas_tey
=========

**Status**:

  *application definition* (contribution), extends :ref:`NXxas`

**Description**:

  .. collapse:: In total electron yield (TEY), the XAS spectrum is measured by ...

      In total electron yield (TEY), the XAS spectrum is measured by
      collecting all secondary electrons emitted from the sample surface.
      The drain current or total electron current :math:`I_{ey}` is
      proportional to the absorption coefficient:

      .. math:: \mu(E) \propto I_{ey}/I_0

      TEY is inherently surface-sensitive because electrons are readily
      absorbed by most materials, limiting the probing depth to a few
      nanometers.

      The top-level :ref:`intensity </NXxas/ENTRY/intensity-field>`
      field stores the ratio :math:`I_{ey}/I_0`. When the raw
      detector data and processing steps are available, they can be stored
      in the optional ``NXinstrument`` and ``NXprocess`` groups,
      enabling full reproducibility of the data reduction.

**Symbols**:

  No symbol table

**Groups cited**:
  :ref:`NXdetector`, :ref:`NXentry`, :ref:`NXinstrument`, :ref:`NXprocess`

.. index:: NXentry (base class); used in application definition, NXinstrument (base class); used in application definition, NXdetector (base class); used in application definition, NXprocess (base class); used in application definition

**Structure**:

  .. _/NXxas_tey/ENTRY-group:

  :bolditalic:`ENTRY`: (required) :ref:`NXentry` :ref:`⤆ </NXxas/ENTRY-group>`


    .. _/NXxas_tey/ENTRY/definition-field:

    .. index:: definition (field)

    **definition**: (required) :ref:`NX_CHAR <NX_CHAR>` :ref:`⤆ </NXxas/ENTRY/definition-field>`

      .. collapse:: Official NeXus NXDL schema to which this file conforms. ...

          Official NeXus NXDL schema to which this file conforms.

          Obligatory value: ``NXxas_tey``

    .. _/NXxas_tey/ENTRY/intensity-field:

    .. index:: intensity (field)

    **intensity**: (required) :ref:`NX_FLOAT <NX_FLOAT>` (Rank: 1, Dimensions: [nEnergy]) {units=\ :ref:`NX_ANY <NX_ANY>`} :ref:`⤆ </NXxas/ENTRY/intensity-field>`

      .. collapse:: The absorption coefficient :math:`\mu(E) \propto I_{ey}/I_0`, ...

          The absorption coefficient :math:`\mu(E) \propto I_{ey}/I_0`,
          where :math:`I_{ey}` is the total electron yield signal.

    .. _/NXxas_tey/ENTRY/INSTRUMENT-group:

    :bolditalic:`INSTRUMENT`: (optional) :ref:`NXinstrument` :ref:`⤆ </NXentry/INSTRUMENT-group>`


      .. _/NXxas_tey/ENTRY/INSTRUMENT/i0-group:

      **i0**: (required) :ref:`NXdetector` :ref:`⤆ </NXinstrument/DETECTOR-group>`

        .. collapse:: Detector measuring the incident beam intensity ...

            Detector measuring the incident beam intensity
            :math:`I_0`.

        .. _/NXxas_tey/ENTRY/INSTRUMENT/i0/data-field:

        .. index:: data (field)

        **data**: (required) :ref:`NX_NUMBER <NX_NUMBER>` (Rank: 1, Dimensions: [nEnergy]) :ref:`⤆ </NXdetector/data-field>`


      .. _/NXxas_tey/ENTRY/INSTRUMENT/iey-group:

      **iey**: (required) :ref:`NXdetector` :ref:`⤆ </NXinstrument/DETECTOR-group>`

        .. collapse:: Detector measuring the total electron yield ...

            Detector measuring the total electron yield
            :math:`I_{ey}` (drain current).

        .. _/NXxas_tey/ENTRY/INSTRUMENT/iey/data-field:

        .. index:: data (field)

        **data**: (required) :ref:`NX_NUMBER <NX_NUMBER>` (Rank: 1, Dimensions: [nEnergy]) :ref:`⤆ </NXdetector/data-field>`


    .. _/NXxas_tey/ENTRY/PROCESS-group:

    :bolditalic:`PROCESS`: (optional) :ref:`NXprocess` :ref:`⤆ </NXentry/PROCESS-group>`

      .. collapse:: Description of how :ref:`intensity ...

          Description of how :ref:`intensity
          </NXxas/ENTRY/intensity-field>` was obtained from
          the raw detector data (i0, iey).

      .. _/NXxas_tey/ENTRY/PROCESS/program-field:

      .. index:: program (field)

      **program**: (optional) :ref:`NX_CHAR <NX_CHAR>` :ref:`⤆ </NXprocess/program-field>`

        Name of the program used for processing.

      .. _/NXxas_tey/ENTRY/PROCESS/version-field:

      .. index:: version (field)

      **version**: (optional) :ref:`NX_CHAR <NX_CHAR>` :ref:`⤆ </NXprocess/version-field>`

        Version of the program used for processing.

      .. _/NXxas_tey/ENTRY/PROCESS/date-field:

      .. index:: date (field)

      **date**: (optional) :ref:`NX_DATE_TIME <NX_DATE_TIME>` :ref:`⤆ </NXprocess/date-field>`

        Date and time of processing.


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

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


* :ref:`/NXxas_tey/ENTRY-group </NXxas_tey/ENTRY-group>`
* :ref:`/NXxas_tey/ENTRY/definition-field </NXxas_tey/ENTRY/definition-field>`
* :ref:`/NXxas_tey/ENTRY/INSTRUMENT-group </NXxas_tey/ENTRY/INSTRUMENT-group>`
* :ref:`/NXxas_tey/ENTRY/INSTRUMENT/i0-group </NXxas_tey/ENTRY/INSTRUMENT/i0-group>`
* :ref:`/NXxas_tey/ENTRY/INSTRUMENT/i0/data-field </NXxas_tey/ENTRY/INSTRUMENT/i0/data-field>`
* :ref:`/NXxas_tey/ENTRY/INSTRUMENT/iey-group </NXxas_tey/ENTRY/INSTRUMENT/iey-group>`
* :ref:`/NXxas_tey/ENTRY/INSTRUMENT/iey/data-field </NXxas_tey/ENTRY/INSTRUMENT/iey/data-field>`
* :ref:`/NXxas_tey/ENTRY/intensity-field </NXxas_tey/ENTRY/intensity-field>`
* :ref:`/NXxas_tey/ENTRY/PROCESS-group </NXxas_tey/ENTRY/PROCESS-group>`
* :ref:`/NXxas_tey/ENTRY/PROCESS/date-field </NXxas_tey/ENTRY/PROCESS/date-field>`
* :ref:`/NXxas_tey/ENTRY/PROCESS/program-field </NXxas_tey/ENTRY/PROCESS/program-field>`
* :ref:`/NXxas_tey/ENTRY/PROCESS/version-field </NXxas_tey/ENTRY/PROCESS/version-field>`

**NXDL Source**:
  https://github.com/FAIRmat-NFDI/nexus_definitions/tree/fairmat/contributed_definitions/NXxas_tey.nxdl.xml