Add Muon DKT for non-zero magnetic field

[Raquel Alvarez Banos]

In ticket #9556 the DKT for zero magnetic field was implemented. Update the code corresponding to HKT() to allow positive fields. The function to implement is described in the documentation.

[Raquel Alvarez Banos]

Re #11086 Add static KT function for magnetic field

Changeset: 8fc0b2d41c0a19e7a63c7d169079dcf2652fbde4

[Raquel Alvarez Banos]

Re #11086 Add function to integrate

Changeset: 068b847d0751c17687b6d59f2e83668b7d657ad6

[Raquel Alvarez Banos]

Re #11086 Add NR routines and update getDKT function

Changeset: 9c15ca4edf8882e8eef5c78f462cc7fdac1c7788

[Raquel Alvarez Banos]

Re #11086 Update fitting function for non zero field

Changeset: 5a6effab6f8164507f7ecde7d72702d54f66d308

[Raquel Alvarez Banos]

Re #11086 Enable and update non-zero field unit tests

Changeset: 80121f8699bf2cccb99db9fb18ccb89fe6b9ebf3

[Raquel Alvarez Banos]

Re #11086 Move integration parameters to function

Changeset: 833a1049ada84941a9ebbf79f91e4c4fd370ec72

[Raquel Alvarez Banos]

Re #11086 Replace error messages with exceptions

Changeset: 1c2bfb9cd271e9a91c1ee625f9cf8bd2d3318462

[Raquel Alvarez]

This is being verified as ​pull request #468.

[Raquel Alvarez Banos]

To test:

• Open the muon analysis interface
• Load the first dataset, EMU00020888.nxs
• Go to "Data Analysis". Add the "DynamicKuboToyabe" fitting function.
• Set the fitting limits to [0.11, 5.016].
• Fit the data. The external magnetic field for this dataset is F=40, you should obtain something close to 41. You may want to zoom in to observe the fitting results in more detail.

• Do not close the interface. Go back to "Home" and load the next dataset, EMU00020889. Hit "Plot" and go to "Data Analysis". Use parameter values from the previous fit for this dataset. Fit the data. The magnetic field F should be around 55.
• Repeat the same steps with the last dataset, EMU00020890. F should be close to 65.

I do not think we should worry about the differences between the real magnetic field (which you can see in the graph) and the fitting results at this stage, as muon scientists usually fix one of the other parameters to a known value, use a different alpha value in the "Grouping Options" tab, or use other options that may give slightly different results. They might even want to fix the magnetic field and just fit the other parameters. As this is something I do not know at the moment, we will need to wait for feedback, and if anything needs to be improved create new tickets.

[Dan Nixon]

Merge pull request #468 from mantidproject/11086_DKT_for_nonzero_field

DynamicKuboToyabe fitting function for non-zero field

Full changeset: ​80bf9143ad02eb1fc54e134d48cea5585bec03b0

[Stuart Campbell]

This ticket has been transferred to github issue ​11925