01SEP17

15.5* MeV/m original LCLS-II baseline [04NOV16] 15.5* MeV/m present 0.25 GeV L2 1.6 GeV L3 4.0 GeV BC2 44.18 m original LCLS-II baseline [04NOV16] COL2 EXT 4 15 16 25 26 35 DB1 15+2 DB2 20 BRB1 (to NIT) 15.5* MeV/m 0.25 GeV L2 1.6 GeV L3 4.0 GeV BC2 present LCLS-II baseline [09MAY17] 284.86 m EMIT2 4 15 16 25 26 35 21 m BRB1 (to NIT) DB1 15+2 DB2 20 NOTE: not to scale 18* MeV/m 20.8* MeV/m 0.25 GeV L2 (φ=-21°) 1.873 GeV L3 (φ=5°) 3.749 GeV L4 (φ=3.8°) 8.0 GeV BC2 40.95 m LCLS-II-HE [next] EMIT2 4 15 16 25 26 28 29 35 41 42 55 12.4 m BRB1 (to NIT) DB1 15+2 DB2 14 DB3 26 accelerating gradients: 18.0 MeV/m includes 3% overhead 20.8 MeV/m includes 6% overhead

BC2 L2 DOG EMIT2 L3 LEX L4 EXT 30° / cell FODO low-energy extraction

NOTE: kickers, septum, and final bend rotated ~50° counter-clockwise

2nd order dispersion correction match to SIT bypass line rotated sextupoles -28° -1° -17° match to SIT bypass line

“Stripline-15” (new type) SLTR QF1545 (a.k.a. QF-1) “1.013Q3.42” SA-446-538-71 bore = 1.013” chamber φ = 0.9” (22.9 mm) core length = 3.42” full core width = 6.5” GLmax = 63.8 kG @ 160 A BPM “Stripline-15” (new type) SA-446-563-30 strip φ = 1.057” (26.9 mm)

septum kickers CM29 L3 L4 CM29 kickers septum

name area type Bmax Egev B % Esgev Bs % ------- ----- ------------ ------ ----- --------- --- ----- --------- --- BKRL3X1 LEDOG 0.787K35.4 0.040 3.749 0.035750 89 4.000 0.038144 95 BKRL3X2 LEDOG 0.787K35.4 0.040 3.749 0.035750 89 4.000 0.038144 95 BKRL3X3 LEDOG 0.787K35.4 0.040 3.749 0.035750 89 4.000 0.038144 95 BKRL3XD LEDOG 1.378K35.4 0.023 3.749 0.020429 89 4.000 0.021796 95 BLRL3X LEDOG 0.625SD38.98 11.000 3.749 10.309746 94 4.000 10.999996 100 BRL3X LEDOG 1.0D38.37 11.000 3.749 10.310544 94 4.000 11.000847 100 name area type GLmax Egev GL % Esgev GLs % QL3X1 LEDOG 1.013Q3.42 63.80 3.749 -57.4057 90 4.000 -61.2490 96 QL3X2 LEDOG 1.013Q3.42 63.80 3.749 57.4057 90 4.000 61.2490 96 QL3X3 LEDOG 1.26Q12 150.00 3.749 -64.5145 43 4.000 -68.8338 46 QL3X4 LEDOG 1.26Q12 150.00 3.749 85.8842 57 4.000 91.6343 61 QL3X5 LEDOG 1.26Q12 150.00 3.749 -63.5880 42 4.000 -67.8453 45 QL3X6 LEDOG 1.26Q12 150.00 3.749 76.5282 51 4.000 81.6519 54 QL3X7 LEDOG 1.26Q12 150.00 3.749 -98.2350 65 4.000 -104.8120 70 QL3X8 LEDOG 1.26Q12 150.00 3.749 100.6448 67 4.000 107.3830 72 name area type G’Lmax Egev G’L % Esgev G’Ls % SL3X1 LEDOG 1.38S3.00 870.00 3.749 510.7907 59 4.000 544.9888 63 SL3X2 LEDOG 1.38S3.00 870.00 3.749 540.7345 62 4.000 576.9374 66 SL3X3 LEDOG 1.38S3.00 870.00 3.749 675.8124 78 4.000 721.0588 83

E= 3.749 GeV, γε= 1 μ, σWS= 250 μ E= 3.749 GeV, γε= 1 μ, σCOLL= 300 μ 45° / cell FODO E= 3.749 GeV, γε= 1 μ, σWS= 250 μ 45° / cell FODO E= 3.749 GeV, γε= 1 μ, σCOLL= 300 μ WS WS WS WS CX CY CX CY

DC merge bend

X Z A-line BSY wooden door SXR DASEL new low-energy dump line LCLS Cu linac scH NIT SIT scS HXR scSX new B-line connector Z

Y Z scH scS new low-energy dump line NIT SIT scSX merge A-line cuS scD LCLS Cu linac NIT SIT DASEL A-line scH scS cuS new low-energy dump line new B-line connector Y Z scSX merge scD scH

NOTE: kickers, septum, and final bend rotated ~2° counter-clockwise

Changes (w.r.t. 04JUL17) L3/L4 split moves 1 cryomodule upstream L3: CM16-CM25(10) / vacuum break / CM26-CM28(3) L4: CM29-CM41(13) / vacuum break / CM42-CM55(14) energy profile (see slide 2) updated gradients, phases, overheads BC2 energy now 1.873 GeV LEX energy now 3.749 GeV (max 4 GeV) low-energy extraction now includes one “DIAG0-style” kicker (25 mm ID pipe) low-energy dogleg now uses 2 “1.013Q3.42” quadrupoles with 2 “Stripline-15” BPMs 6 “1.26Q12” quadrupoles with 6 “Stripline-6” BPMs numbered of powered spreader kickers for both HXR and SXR increased to 5, plus one “DIAG0-style” kicker (25 mm ID pipe) at the end of each string low-energy dump line now included possible future connector between BSY dump line and B-line tunnel included will not be released as part of baseline

Issues no dedicated differential pumping stay-clear spaces at end of L3 and beginning of L4 … pumps assumed to be interleaved with other devices in warm section (assumed particle-free) only one R56 compensation chicane associated with low-energy dogleg (at downstream end) dogleg R56 = -2.3 mm (maximum R56 in compensation chicane at 4 GeV is 0.943 mm) SXR safety dump bends (permanent magnets) at 8 GeV B-field of safety dump bends magically doubled in MAD deck to retain layout