UB Matrix for Triple Axis Instruments

> CELL a b c alpha beta gamma

set unit cell constants. If b or c are omitted, a is used, if angles are omitted, they are set to 90 degress. Without arguments, the cell constants are listed.

> REF h k l a4 a3 sgl sgu

enter h k l to the list of reflections. For angles not given, the current motor positions are used. A new, unused reflection name is given and show. If peak is specified, the named reflection is overwritten. Reflection names are single letters starting from A. It is possible to save the information about up to 26 reflections.

> REF peak h k l a4 a3 sgl sgu

The same as above, but a named peak is overwritten.

> REF CLEAR peak

Remove the named peak.

> REF CLEAR

Remove all peaks.

> CALCUB peak1 peak2

Calculate and print out the UB matrix. If two peaks are given, peak1 is used as the main peak, i.e. driving to the angles given for this peak will correspond to a QHKL which may only differ by a scalar factor of about one, if the cell constants are not correct. peak2 is used only for determining the scattering plane.

> CALCUB peak1 peak2 CHEAT

The same as above, but the cell constants a, b and c are scaled in order to make peak1 perfectly fitting.

> CALCUB peak1 peak2 peak3

The cell constants are calculated back from the three peaks and printed out.

> MAKEUB peak1 peak2 peak3?

Calculate the UB matrix and make it active. The arguments are the same as in CALCUB. Without arguments, the last calculated UB matrix is used.

> LISTUB

List the UB matrix, the cell constants and all stored reflections.