CalibrateRectangularDetectors-v1.rst

Description

Here are examples of input and output from PG3 and SNAP:

The purpose of this algorithm is to calibrate the detector pixels and write a calibration file. The calibration file name contains the instrument, run number, and date of calibration. A binary Dspacemap file that converts from TOF to d-space including the calculated offsets is also an output option. For CrossCorrelation option: If one peak is not in the spectra of all the detectors, you can specify the first n detectors to be calibrated with one peak and the next n detectors to be calibrated with the second peak. If a color fill plot of the calibrated workspace does not look good, do a color fill plot of the workspace that ends in cc (cross correlation) to see if the CrossCorrelationPoints and/or PeakHalfWidth should be increased or decreased. Also plot the reference spectra from the cc workspace.

Features to improve performance of peak finding

Define peak fit-window

There are two exclusive approaches to define peak's fit-window.

• PeakWindowMax All peaks will use this value to define their fitting range.
• FitwindowTableWorkspace This is a table workspace by which each peak will have its individual fit window defined.

Define accepted range of peak's width

Optional input property DetectorResolutionWorkspace is a matrix workspace containing the detector resolution \Delta(d)/d for each spectrum. Combining with property AllowedResRange, it defines the lower and upper limit for accepted fitted peak width.

Let c_l = AllowedResRange[0], c_h = AllowedResRange[1] and fwhm as the peak's fitted width. Then,

c_l\times\frac{\Delta(d)}{d} < fwhm < c_h\times\frac{\Delta(d)}{d}