'Prepare Regions' Menu

For normal (i.e. non-EXAFS) region scans the Prepare regs button invokes a widget that is displayed here 7.6. The region limits, the sept width and the sample time can be supplied. The buttons 'Reg 1', 'Reg 2', etc. can be used to delete or duplicate regions.

For EXAFS scans the Prepare regs button invokes a widget that has additional columns for an edge position and an exponent. If the edge position of a region is set to 0, it is transversed with constasnt energy steps. Otherwise the steps are adjusted to be constant in k. The exponent column allows an adjustment of the sample time for constant-k regions: $st \rightarrow st\times k_n^power$. $k_n$ is the normalized momentum. It is 1 at the start of a region. Online makes sure that sample time is always a multiple of 20 msec in order to avoid interferences with a 50 Hz background.

Figure 7.6: The Regions Widget

Figure 7.7: The EXAFS Regions Widget