CLS, Saskatoon, Saskatchewan, Canada
At the Canadian Light Source (CLS) synchrotron, the addition of the Quantum Materials Spectroscopy Centre (QMSC) beamline requires the addition of an Elliptically Polarizing Undulator (EPU) insertion device to produce photons from the stored electron beam. Unlike the majority of such insertion devices, this EPU is capable of producing photons of simultaneous arbitrary elliptical and linear phases, in addition to a range of energies. This EPU is also capable of creating perturbations of the stored electron beam sufficient to cause an interruption of an injection. In order to prevent this, compensation controls have been developed. These controls are accomplished with a combination of Experimental Physics and Industrial Control System (EPICS), mathematical models, and algorithms written in C and MATLAB.
