This page will detail the latest modifications to the D17 LAMP suite

d17_xspec

Realised that SANOFF = 'auto' will not work when METHOD='smpl' (which happens to be the default) was selected.  This now works.

d17_xspec

Included an optional variable, SNORM, which will normalize the data to slit sizes and/or Qz.  This corresponds to a footprint or incident intensity correction.

d17_he3calc

Changed the method for calculating the integrated intensity to make it more robust.  The routine now estimates a fit range based on the weighted standard deviation of the data, then fits a Gaussian to give an estimate of the background, then sums the data in the range, subtracting the data to give the integrated intensity.  The background is assumed to be flat, and all main beam measurements and polchecks should be made well away from the edges of the detector whene no counts are registered.

d17_he3fit

Introduced a new optional parameter, DSEL, which will allow data points to be deselected.

aw_startmono

Following requests for scans optimized for off-specular, new scan types have been included.  The scan types are:

theta-twotheta:  Moves the sample by an angle (theta) between points and moves the detector by twice the angle (twotheta).  This is the default, it is best for measuring specular scattering, and is necessary for using the supermirror analyser.

theta-theta: Moves the sample by an angle (theta) between points and moves the detector by the same angle.  Has the advantage that the output data is automatically in the coordinates theta out vs. theta in.

DAN fixed: Moves the detector to a position and then scans the sample angle.  Is the best optimized for looking at Bragg sheets, correlated roughness, etc.

More info here.

mload

Have added S2W and S3W to the 'pv' field that goes with a LAMP workspace.  Each row in the data will now have the corresponding values of the slits recorded, and the data can be normalized to incident intensity by dividing by the slit sizes if required.

pv now is an array with M*8 (rows * columns) elements, where M is the number of data points in the measurement.  The columns are:

1st column:     SAN

2nd column:    DAN

3rd column:     mean date (for ³He measurements)

4th column:     count time

5th column:     monitor

6th column:     normalization factor (usually the count time)

7th column:     S2W

8th column:     S3W

d17_xyconvert

Have adapted it to convert both monochromatic and TOF datasets.

TOF datasets come with new axis possibilities such as 2theta vs. lambda

d17_xspec

Have introduced a new module for extracting the specular data from a monochromatic measurement.  The new module replaces xspec, which will continue to be in the runtime for backwards compatibility.

The new module has new background subtraction methods, suitable for bent substrates and for measurements with strong off-specular scattering

d17_he3fit

Corrected bug in runtime version.  It did not run previously, it will now run correctly.

d17_xyconvert

Have included 'auto' option for automatically determining any SAN offset

Have included 'datp' as input so d17_xyconvert can be called from another subroutine.