New 135-MeV injector energy requires minor changes to linac operating point…

(easy)

(July 9, 2003) LCLS Accelerator and Compressor Schematic SLAC linac tunnel undulator hall Linac-0 L =6 m Linac-1 L =9 m  rf =  25° Linac-2 L =330 m  rf =  41° Linac-3 L =550 m  rf =  13° BC-1 L =6 m R 56 =  39 mm BC-2 L =22 m R 56 =  25 mm DL-2 L =66 m R 56 = 0 DL-1 L =12 m R 56  0 undulator L =120 m 6 MeV  z  0.83 mm    0.01 % 135 MeV  z  0.83 mm    0.10 % 250 MeV  z  0.19 mm    1.6 % 4.54 GeV  z  mm    0.71 % GeV  z  mm    0.02 %...existing linac new rfgun 25-1a30-8c21-1b21-1d X Linac-X L =0.6 m  rf =  21-3b24-6d

 No engineering changes made – all changes are in operational parameters  DL1 bend fields are reduced from kG to kG  X-band rf phase tolerance almost 2-times looser  Mean Ls rf phase tolerance 2-times looser  L1 rf gradient reduced to very reasonable 16.8 MV/m  Old parameter set still possible with only ‘control-room’ adjustments