NXspectrum_set_em_eels

Status:

base class, extends NXobject

Description:

Container for reporting a set of electron energy loss (EELS) spectra.

Virtually the most important case is that spectra are collected in a scanning microscope (SEM or STEM) for a collection of points. The majority of cases use simple d-dimensional regular scan pattern, such as single point, line profiles, or (rectangular) surface mappings.

The latter pattern is the most frequently used. For now the base class provides for scans for which the settings, binning, and energy resolution is the same for each scan point.

Symbols:

n_y: Number of pixel per EELS mapping in the slow direction.

n_x: Number of pixel per EELS mapping in the fast direction.

n_energy_loss: Number of electron energy loss bins.

Groups cited:

NXdata, NXprocess

Structure:

PROCESS: (optional) NXprocess

Details how EELS spectra were processed from the detector readings.

source: (optional) NX_CHAR

Typically the name of the input, (vendor) file from which all the NXdata instances in this NXspectrum_set_em_eels were loaded during parsing to represent them in e.g. databases.

@version: (optional) NX_CHAR

An at least as strong as SHA256 hashvalue of the dataset/file which represents the source digitally to support provenance tracking.

program: (optional) NX_CHAR

Commercial or otherwise given name to the program which was used to process detector data into the EELS spectra stack and summary.

@version: (optional) NX_CHAR

Program version plus build number, commit hash, or description of an ever persistent resource where the source code of the program and build instructions can be found so that the program can be configured in such a manner that the result file is ideally recreatable yielding the same results.

stack: (optional) NXdata

Collected EELS spectra for all pixels of a rectangular region-of-interest. This representation supports rectangular scan pattern.

@long_name: (optional) NX_CHAR

EELS counts

counts: (optional) NX_NUMBER (Rank: 3, Dimensions: [n_y, n_x, n_energy_loss]) {units=NX_UNITLESS}

ypos: (optional) NX_NUMBER (Rank: 1, Dimensions: [n_y]) {units=NX_LENGTH}

Pixel center of mass position y-coordinates.

@long_name: (optional) NX_CHAR

Label for the y axis.

xpos: (optional) NX_NUMBER (Rank: 1, Dimensions: [n_x]) {units=NX_LENGTH}

Pixel center of mass position x-coordinates.

@long_name: (optional) NX_CHAR

Label for the x axis.

energy_loss: (optional) NX_NUMBER (Rank: 1, Dimensions: [n_energy_loss]) {units=NX_ENERGY}

Pixel center of mass energy loss bins.

@long_name: (optional) NX_CHAR

Label for the energy loss axis.

summary: (optional) NXdata

Accumulated EELS spectrum over all pixels of a rectangular region-of-interest. This representation supports rectangular scan pattern.

@long_name: (optional) NX_CHAR

Counts electrons with an energy loss within binned range.

counts: (optional) NX_NUMBER (Rank: 1, Dimensions: [n_energy_loss]) {units=NX_UNITLESS}

Counts for specific energy losses.

energy_loss: (optional) NX_NUMBER (Rank: 1, Dimensions: [n_energy_loss]) {units=NX_ENERGY}

Pixel center of mass energy loss bins.

@long_name: (optional) NX_CHAR

Energy loss

Hypertext Anchors

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

NXDL Source:

https://github.com/FAIRmat-Experimental/nexus_definitions/tree/fairmat/contributed_definitions/NXspectrum_set_em_eels.nxdl.xml