Figure 6
Magnet configurations and beta-functions for the whole beamline (sections S1, S2, S3 and the undulator) for the three set-ups of \(R_{56}\). (a) \(R_{56}={0.20}\,\text{mm}\) (chicane-like), (b) \(R_{56}={0.00}\,\text{mm}\) (neutral) and (c) \(R_{56}={-0.22}\,\text{mm}\) (dogleg-like). The magnet configuration is shown above each plot, which includes: focusing quadrupoles (upper empty rectangles); defocusing quadrupoles (lower empty rectangles); offset defocusing quadrupoles (red filled rectangles) and the undulator (black filled rectangle). The magnet strengths vary between each \(R_{56}\) set-up. However, the configuration (order of focusing and defocusing quadrupoles) only varies in the final section of the beamline (S3); between the last offset quadrupole and the undulator. Each set-up produces maximum beta-function values in the focusing section (S1) and small values through the undulator. The beam transport length from the plasma exit to the undulator entrance (sections S1, S2 and S3) is 11.5 m.
