base class, extends NXobject


A monitor of incident beam data.

It is similar to the NXdata groups containing monitor data and its associated dimension scale, 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.


No symbol table
Groups cited:
NXgeometry, NXlog


mode: (optional) NX_CHAR

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}

Distance of monitor from sample

range[2]: (optional) NX_FLOAT {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[ref(efficiency)]: (optional) NX_FLOAT {units=NX_TIME_OF_FLIGHT}


efficiency[ref(i)]: (optional) NX_NUMBER {units=NX_DIMENSIONLESS}

Monitor efficiency

data[n]: (optional) NX_NUMBER {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 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

integral_log: (optional) NXlog

Time variation of monitor counts

(geometry): (optional) NXgeometry

Geometry of the monitor
NXDL Source: