\(\renewcommand\AA{\unicode{x212B}}\)
Table of Contents
This should be the first command in a user file for the following instruments:
BACK is used to specify a time region in which to measure the (time-independent) neutron background count level. The background is calculated and subtracted from the monitor and transmission spectra before the data are rebinned into wavelength. It is possible to set the TOF time window for all monitors or just one specific monitor.
DET specifies which detector data is to be corrected, or whether detector position encoder values are to be corrected.
Note for now that the /CORR commands only have an effect on SANS2D.
DET/CORR/FRONT/qualifier [parameter]
DET/CORR/REAR/qualifier [parameter]
DET/FRONT
DET/REAR
DET/BOTH
DET/MERGED
DET/MERGE
DET/MAIN
DET/HAB
DET/RESCALE rescale
DET/SHIFT shift
DET/RESCALE/FIT [Q1 Q2]
DET/SHIFT/FIT [Q1 Q2]
FIT specifies whether the calculated transmission data should be fitted to a simple function. Subsequent data treatment then uses values interpolated from the function. Fitting can improve the statistical quality of transmission data and is implemented by CalculateTransmission.
FIT/TRANS/CLEAR or FIT/TRANS/OFF
FIT/TRANS/LIN [w1 w2] or FIT/TRANS/LINEAR [w1 w2] or FIT/TRANS/STRAIGHT [w1 w2]
FIT/TRANS/LOG [w1 w2] or FIT/TRANS/YLOG [w1 w2]
FIT/MONITOR time1 time2
FIT/TRANS/[CAN/|SAMPLE/][LIN|LOG|POLYNOMIAL[2|3|4|5]]
If SAMPLE or CAN is not provided, it is assumed that the FIT/TRANS option applies to both.
GRAVITY specifies whether detector data should be corrected for the ballistic effects of gravity on the neutrons. This correction is particularly important at long sample-detector distances and long wavelengths.
COMPATIBILITY specifies whether the new backend should be run in compatibility mode such that it produces identical results to the old backend.
L specifies various limits that configure or constrain the data reduction process. Note that the command is L and not LIMIT!
L/PHI[/NOMIRROR] d1 d2**
L/Q/ q1 q2 [dq[/LIN]] or L/Q q1 q2 [dq[/LOG]]
L/Q q1 dq1 q3 dq2 q2 or L/Q q1 -dq1 q2 -dq2 q3 (for logarithmic steps)
L/Q/RCut c
L/Q/WCut c
L/QXY qxy1 qxy2 [dqxy[/LIN]] or L/QXY qxy1 qxy2 [dqxy[/LOG]]
L/QXY qxy1 dqxy1 qxy2 dqxy2 qxy3 [/LIN]] or L/QXY qxy1 dqxy1 qxy2 dqxy2 qxy3 [/LOG]]
L/R r1 r2
L/WAV l1 l2 [dl[/LIN] or L/WAV l1 l2 [dl[/LOG]
L/WAV l1 dl1 l3 dl2 l2 [/LIN] or L/WAV l1 dl1 l3 dl2 l2 [/LOG]
L/EVENTSTIME rebin_str
MASK commands clear or implement detector spatial or time masks. Masked regions of the detector or time-of-flight spectra are not included in any data reduction.
Note that the shadow of the beam stop, and the corners of the detector, are masked automatically.
Also note that there is no equivalent in Mantid of the COLETTE box mask MASK x1 x2 y1 y2 where X & Y were specified in mm.
MASK/CLEAR[/TIME]
MASK[/REAR/FRONT/HAB] Hn[>Hm] or MASK Vn[>Vm] - to mask single wires or 'strips'
MASK[/REAR/FRONT/HAB] Hn>Hm+Vn>Vm - to mask a rectangular 'box'
MASK Ssp1[>Ssp2]
MASK/TIME t1 t2 or MASK/T t1 t2
MASK/LINE width angle [x y]
The MASKFILE command enables users to pull in Mask Files created using the Instrument View. For more details on the format of the files, please see the LoadMask algorithm.
Multiple mask files can be specified with a comma-separated list.
None
MON commands control aspects of the data normalisation, such as detector efficiencies, flood source calibrations, and the identity and Z locations of beam monitors.
MON/DIRECT[/FRONT]=drive:\folder\det_effic_file.ext or MON/DIRECT[/REAR]=drive:\folder\det_effic_file.ext
MON/FLAT[/FRONT]=drive:\folder\flat_cell_file.ext or MON/FLAT[/REAR]=drive:\folder\flat_cell_file.ext
MON/HAB=drive:\folder\hab_effic_file.ext
MON/LENGTH=z sp [/INTERPOLATE] or MON/LENGTH=z sp [/INTERPOLATE]
MON[/TRANS]/SPECTRUM=sp [/INTERPOLATE] or MON[/TRANS]/SPECTRUM=sp [/INTERPOLATE]
None
SAMPLE allows for a correction to the default sample position Z coordinate; ie, along the beam axis. It is used to enable or disable the correction for wide angle.
/OFFSET /PATH
SET defines the values of parameters critical to the data reduction process.
SET CENTRE[/MAIN] x y
SET CENTRE/HAB x y
SET SCALES s a b c d
Note x and y are in units of mm. For LOQ instrument, the origin is at te bottom left corner of the main detector.
TRANS is used to control how the proportion of neutrons transmitted through the sample is calculated. This can be calculated using CalculateTransmission or from a specified workspace.
TRANS/TRANSPEC=n
TRANS/SHIFT=d m
TRANS/SAMPLEWS=ws1
TRANS/CANWS=ws2
TRANS/TRANSPEC=m/SHIFT=d
TRANS/RADIUS=r
TRANS/ROI=roi_mask.xml
TRANS/MASK=mask.xml
The TUBECALIBFILE command enables users to pull in a tube calibration file during the data reduction process.
A current limitation of this command is that it only accepts a single tube calibration file.
None
The QRESOLUTION command enables users to calculate the QResolution when the Q1D algorithm is run. Most settings are directly used by the TOFSANSByResolution algorithm
QRESOL/ON
QRESOL/OFF
QRESOL/DELTAR=dr
QRESOL/LCOLLIM="lcollim"
QRESOL/MODERATOR=moderator_rkh_file.txt
QRESOL/A1="a1"
QRESOL/A2="a2"
QRESOL/H1="h1"
QRESOL/H2="h2"
QRESOL/W1="w1"
QRESOL/W2="w2"