3.3.2.18. NXtas

Status:

application definition, extends NXobject, version 1.0b

Description:

This is an application definition for a triple axis spectrometer.

It is for the trademark scan of the TAS, the Q-E scan. For your alignment scans use the rules in NXscan.

Symbols:

No symbol table

Groups cited:

NXcrystal, NXdata, NXdetector, NXentry, NXinstrument, NXmonitor, NXsample, NXsource

Structure:

entry: NXentry

title: NX_CHAR

start_time: NX_DATE_TIME

definition: NX_CHAR

Official NeXus NXDL schema to which this file conforms

Obligatory value: NXtas

(instrument): NXinstrument

(source): NXsource

name: NX_CHAR

probe: NX_CHAR

Any of these values: neutron | x-ray

monochromator: NXcrystal

ei[np]: NX_FLOAT {units=NX_ENERGY}

rotation_angle[np]: NX_FLOAT {units=NX_ANGLE}

analyser: NXcrystal

ef[np]: NX_FLOAT {units=NX_ENERGY}

rotation_angle[np]: NX_FLOAT {units=NX_ANGLE}

polar_angle[np]: NX_FLOAT {units=NX_ANGLE}

(detector): NXdetector

data[np]: NX_INT

polar_angle[np]: NX_FLOAT {units=NX_ANGLE}

(sample): NXsample

name: NX_CHAR

Descriptive name of sample

qh[np]: NX_FLOAT {units=NX_DIMENSIONLESS}

qk[np]: NX_FLOAT {units=NX_DIMENSIONLESS}

ql[np]: NX_FLOAT {units=NX_DIMENSIONLESS}

en[np]: NX_FLOAT {units=NX_ENERGY}

rotation_angle[np]: NX_FLOAT {units=NX_ANGLE}

polar_angle[np]: NX_FLOAT {units=NX_ANGLE}

sgu[np]: NX_FLOAT {units=NX_ANGLE}

sgl[np]: NX_FLOAT {units=NX_ANGLE}

unit_cell[6]: NX_FLOAT {units=NX_LENGTH}

orientation_matrix[9]: NX_FLOAT {units=NX_DIMENSIONLESS}

(monitor): NXmonitor

mode: 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: NX_FLOAT

preset value for time or monitor

data[np]: NX_FLOAT {units=NX_ANY}

Total integral monitor counts

(data): NXdata

One of the ei,ef,qh,qk,ql,en should get a primary=1 attribute to denote the main scan axis

ei –> /NXentry/NXinstrument/monochromator:NXcrystal/ei

ef –> /NXentry/NXinstrument/analyzer:NXcrystal/ef

en –> /NXentry/NXsample/en

qh –> /NXentry/NXsample/qh

qk –> /NXentry/NXsample/qk

ql –> /NXentry/NXsample/ql

data –> /NXentry/NXinstrument/NXdetector/data

NXDL Source:

https://github.com/nexusformat/definitions/blob/master/applications/NXtas.nxdl.xml