3.3.2.14. NXsastof

Status:

application definition, extends NXobject

Description:

raw, 2-D SAS data with an area detector with a time-of-flight source

It covers all raw data from any SAS techniques that use an area detector at a time-of-flight source.

Symbols:

No symbol table
Groups cited:
NXcollimator, NXdata, NXdetector, NXentry, NXgeometry, NXinstrument, NXmonitor, NXsample, NXshape, NXsource

Structure:

(entry): (required) NXentry

@entry: (required) NX_CHAR

NeXus convention is to use “entry1”, “entry2”, … for analysis software to locate each entry

title: (required) NX_CHAR

start_time: (required) NX_DATE_TIME

definition: (required) NX_CHAR

Official NeXus NXDL schema to which this file conforms

Obligatory value: NXsastof

instrument: (required) NXinstrument

name: (required) NX_CHAR

Name of the instrument actually used to perform the experiment

source: (required) NXsource

type: (required) NX_CHAR

type of radiation source

name: (required) NX_CHAR

Name of the radiation source

probe: (required) NX_CHAR

Any of these values: neutron | x-ray

collimator: (required) NXcollimator

geometry: (required) NXgeometry

shape: (required) NXshape

shape: (required) NX_CHAR

Any of these values: nxcylinder | nxbox

size: (required) NX_FLOAT {units=NX_LENGTH}

The collimation length

detector: (required) NXdetector

data[nXPixel, nYPixel, nTOF]: (required) NX_NUMBER

This is area detector data, of number of x-pixel versus number of y-pixels. Since the beam center is to be determined as a step of data reduction, it is not necessary to document or assume the position of the beam center in acquired data.

time_of_flight[nTOF]: (required) NX_FLOAT {units=NX_TIME_OF_FLIGHT}

distance: (required) NX_FLOAT {units=NX_LENGTH}

The distance between detector and sample

x_pixel_size: (required) NX_FLOAT {units=NX_LENGTH}

Physical size of a pixel in x-direction

y_pixel_size: (required) NX_FLOAT {units=NX_LENGTH}

Size of a pixel in y direction

polar_angle: (required) NX_FLOAT {units=NX_ANGLE}

azimuthal_angle: (required) NX_FLOAT {units=NX_ANGLE}

rotation_angle: (required) NX_FLOAT {units=NX_ANGLE}

aequatorial_angle: (required) NX_FLOAT {units=NX_ANGLE}

beam_center_x: (required) NX_FLOAT {units=NX_LENGTH}

This is the x position where the direct beam would hit the detector. This is a length, not a pixel position, and can be outside of the actual detector.

beam_center_y: (required) NX_FLOAT {units=NX_LENGTH}

This is the y position where the direct beam would hit the detector. This is a length, not a pixel position, and can be outside of the actual detector.

sample: (required) NXsample

name: (required) NX_CHAR

Descriptive name of sample

aequatorial_angle: (required) NX_FLOAT {units=NX_ANGLE}

control: (required) NXmonitor

mode: (required) NX_CHAR

Count to a preset value based on either clock time (timer) or received monitor counts (monitor).

Any of these values: monitor | timer

preset: (required) NX_FLOAT

preset value for time or monitor

data[nTOF]: (required) NX_INT

time_of_flight[nTOF]: (required) NX_FLOAT {units=NX_TIME_OF_FLIGHT}

data: (required) NXdata

data –> /NXentry/NXinstrument/NXdetector/data

time_of_flight –> /NXentry/NXinstrument/NXdetector/time_of_flight

NXDL Source:
https://github.com/nexusformat/definitions/blob/master/applications/NXsastof.nxdl.xml