2.3.3.1.42. NXmonitor

Status:

base class, extends NXcomponent

Description:

A monitor of incident beam data. ...

A monitor of incident beam data.

It is similar to the NXdata groups containing monitor data and its associated axis coordinates, e.g. time_of_flight or wavelength in pulsed neutron instruments. However, it may also include integrals, or scalar monitor counts, which are often used in both in both pulsed and steady-state instrumentation.

Symbols:

No symbol table

Groups cited:

NXgeometry, NXlog, NXoff_geometry

Structure:

mode: (optional) NX_CHAR

Count to a preset value based on either clock time (timer) ...

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

Any of these values: monitor | timer

start_time: (optional) NX_DATE_TIME

Starting time of measurement

end_time: (optional) NX_DATE_TIME

Ending time of measurement

preset: (optional) NX_NUMBER {units=NX_ANY}

preset value for time or monitor

distance: (optional) NX_FLOAT {units=NX_LENGTH}

DEPRECATED: Use transformations/distance instead

Distance of monitor from sample

range: (optional) NX_FLOAT (Rank: 1, Dimensions: [2]) {units=NX_ANY}

Range (X-axis, Time-of-flight, etc.) over which the integral was calculated

nominal: (optional) NX_NUMBER {units=NX_ANY}

Nominal reading to be used for normalisation purposes.

integral: (optional) NX_NUMBER {units=NX_ANY}

Total integral monitor counts

type: (optional) NX_CHAR

Any of these values: Fission Chamber | Scintillator

time_of_flight: (optional) NX_FLOAT (Rank: same as field efficiency, Dimensions: same as field efficiency) {units=NX_TIME_OF_FLIGHT}

Time-of-flight

efficiency: (optional) NX_NUMBER (Rank: same as field i, Dimensions: same as field i) {units=NX_DIMENSIONLESS}

Monitor efficiency

data: (optional) NX_NUMBER (Rank: dataRank) {units=NX_ANY}

Monitor data

sampled_fraction: (optional) NX_FLOAT {units=NX_DIMENSIONLESS}

Proportion of incident beam sampled by the monitor (0<x<1)

count_time: (optional) NX_FLOAT {units=NX_TIME}

Elapsed actual counting time, can be an array of size ``np`` ...

Elapsed actual counting time, can be an array of size np when scanning. This is not the difference of the calendar time but the time the instrument was really counting, without pauses or times lost due beam unavailability

depends_on: (optional) NX_CHAR ⤆

The reference plane of the monitor contains the surface of the detector that f ...

The reference plane of the monitor contains the surface of the detector that faces the source and is the entry point of the beam. The reference point of the monitor in the x and y axis is its centre on this surface. The reference plane is orthogonal to the the z axis and the reference point on this z axis is where they intersect.

../../_images/monitor.png

integral_log: (optional) NXlog ⤆

Time variation of monitor counts

GEOMETRY: (optional) NXgeometry

DEPRECATED: Use the field depends_on and NXtransformations to position the monitor and NXoff_geometry to describe its shape instead

Geometry of the monitor

OFF_GEOMETRY: (optional) NXoff_geometry

This group describes the shape of the beam line component

Hypertext Anchors

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

NXDL Source:

https://github.com/FAIRmat-NFDI/nexus_definitions/tree/fairmat/base_classes/NXmonitor.nxdl.xml