Fig. 5.

Beam pointing alignment compensation alignment method. Superimposed images with the appropriate adjustment of the QUAPEVA magnetic axis. a Case of screen in the middle of the chicane where the beam is horizontally dispersed, correction of the vertical dispersion (from I to II). On screen located at the undulator entrance: b initial beam (I), with artificial vertical dispersion introduced (II), with horizontal dispersion corrected (III), with artificial vertical dispersion removed (IV), c beam experimental transverse position control with respect to expected displacements from the model (black crosses)