XFEL Operations

A short trick to keep the SASE pulse energy constantly high over a longer period of time:  You probably remember that we used to have the gun phase vs pulse intensity correlation plot open and use it to adjust the gun phase when necessary. This went well until the gun LLRF got an update. Since then, the gun phase is too stable for the correlation plot. However, it is probably still necessary to adjust the Gun Phase occasionally. For example,…

The big brother server now monitors the signal of the HIREX spectrometers for SASE1 and SASE2. If the value of a single pixel exceeds the defined thresholds, the beam for the corresponding undulator beamline is stopped. Beam is only allowed back if the "Reset Alarm" button on the big brother server panel is pressed or if the HIREX spectrometer is taken out of the beam. Warning and alarm indicators are also displayed on the big status monitor in the control room. image2021-7-16_15-51-55.png

The presets for the Ocelot optimizer have been revised and extended. They were divided into 5 groups: Dispersion correction, Injector elements with impact on all beamlines and the usual sets for the respective undulator beamlines SASE1, SASE2 and SASE3.  As you can see, the dispersion correction options have been expanded to include B1 and B2 sections. Please remember that the trajectory as well as the compression feedback loops should be opened before the dispersion correction starts!…