Implement gamma correction for vesuvio

[Martyn Gigg]

Andrew Seel has sent the fortran code for the current gamma correction on VMS. We need to include this within Mantid.

The attached image shows the results from the VMS manual.

[Martyn Gigg]

Add foil & foil-changer positions to Vesuvio IDF.

Refs #8378

Changeset: 125d559f02e864cb1edf603e3648e079c4d49c03

[Martyn Gigg]

Rename VESUVIO analyser parameters to make way for foil parameters.

There are foil parameters that will require similar names so they have been made more explicit. Refs #8378

Changeset: 68b834993da79d891cf538a4bcdc6b8097576b80

[Martyn Gigg]

Add resolution parameters for the foil components.

Refs #8378

Changeset: 7dfd416920aeb81b0988b0dcad45656cd863ac68

[Martyn Gigg]

Skeleton algorithm & test.

Refs #8378

Changeset: 0b5f5561908cfd44358cb6f7f5a33223e52fdb3c

[Martyn Gigg]

Have separate names in Vesuvio definition for foils in position 0 & 1.

Refs #8378

Changeset: 5a4e7e52d8495f716a86f703b6ef42b21e246ee1

[Martyn Gigg]

Add/rename some helper methods in ComptonProfileTestHelpers.

Refs #8378

Changeset: 8e62e0cbfc68827e50cc9be080fdd6587bf1eb82

[Martyn Gigg]

Fix VESUVIO foil shape/location definitions.

The shapes are slightly more accurate to improve theta calculation. Refs #8378

Changeset: 3af0c0cc7d4d72746d48791157bfeeacaa833c39

[Martyn Gigg]

Algorithm now caches required instrument geometry.

Refs #8378

Changeset: f39772071928b3ac5a0f2a46a8a2d63cc9593cd4

[Martyn Gigg]

Convert CalculateGammaBackground to use input function.

This will allow it to use the same function types that has been set during the fitting procedure and does not then hard-code the mass profiles that will be used to calculate the spectrum. VESUVIO parameters have been tidied up and the foil-specific ones added. Refs #8378

Changeset: 6e6f7e1732cfbcf785fdeead97c2e356f0b872cd

[Martyn Gigg]

Fix foil position definitions so that they sit at phi=0

The foil-changer also has been changed to switch the radius with the height. This now gives the correct integration range for CalculateGammaBackground Refs #8378

Changeset: cca181b5ffc08425809ea3467a46b9e6258ee6b1

[Martyn Gigg]

Fix the theta/phi angles for the forward scattering detectors.

They all had the incorrect sign as the VMS detpos.dat file says that they all belong in the mirror positions to each other. The absolute scattering angle remains the same so the original fitting is unaffected. It does, however, affect the gamma background calculation as this relies on knowing the distance between a given foil & detector. Refs #8378

Changeset: 4c8c3b51fe39f89df419028b34a8113a4386f170

[Martyn Gigg]

Fix spectrum Y values that do not fall in forward scattering range.

Refs #8378

Changeset: d2e7e1e2bc4216d881614a88b6c6be960423f3f5

[Martyn Gigg]

Fix ComptonProfile attribute storage.

If the base class method is not called then the IFunction::asString method does not work as expected. Refs #8378.

Changeset: 4095a83f5da06ae23e660a89d033224a433a66ac

[Martyn Gigg]

Refactor tests to use the same helper function.

This eliminates a function that was not used in some cpp files and could cause a compiler warning. Refs #8378

Changeset: 4da04053c1ac735b54c7a9e6cdc3f1429aa22d42

[Martyn Gigg]

Branch: feature/8378_gamma_correction

Tester: The required files are EVS14188-14195 on the ISIS archive along with the attached IP file. Download the IP file & tick archive searching in the manage user directories and this should fine the required files. The script is a stripped down version of what would be used by the users. The Fit-like function string will usually be created by a separate method using the results from an earlier Fit.

Here the results of plotting the final 3 workspaces together should reproduce the attached image from the VMS manual. As usual ultimate acceptance will have to be provided by the instrument scientists but this should at least give a very good start.

from mantid.simpleapi import *

#
# Load
# 
runs = "14188-14195"
spectra = "135-142"
diff_type="SingleDifference" # Allowed values=Single,Double,Thick
ip_file = "IP0004_10.par"

raw_ws = LoadVesuvio(Filename=runs, SpectrumList=spectra,
                     Mode=diff_type,InstrumentParFile=ip_file)
raw_ws = CropWorkspace(raw_ws,XMin=50.0,XMax=562.0)


#
# Correct - Usually this string would come out of being constructed from Fit
#
mass1_str = "name=GramCharlierComptonProfile,WorkspaceIndex=0,Mass=1.007900,HermiteCoeffs=1 0 0,Width=4.226288,FSECoeff=0.498073,C_0=57.941101"
mass2_str = "name=GaussianComptonProfile,WorkspaceIndex=0,Mass=27.000000,Width=13.000000,Intensity=1.626268"
mass3_str = "name=GaussianComptonProfile,WorkspaceIndex=0,Mass=91.200000,Width=26.000000,Intensity=2.977515"
func_str = "%s;%s;%s" %(mass1_str,mass2_str,mass3_str)

background,corrected = CalculateGammaBackground(InputWorkspace=raw_ws, ComptonFunction=func_str)

raw_ws = SumSpectra(InputWorkspace=raw_ws)
background = SumSpectra(InputWorkspace=background)
corrected = SumSpectra(InputWorkspace=corrected)

[Roman Tolchenov]

Merge remote-tracking branch 'origin/feature/8378_gamma_correction'

Full changeset: ​763efca88d62a873a55fbf7285b4cb0a0c5d3ca4

[Stuart Campbell]

This ticket has been transferred to github issue ​9223