LCLS2sc MAD files: Injector to Bypass Line lattice version 1.2 (October 30, 2013) M. Woodley SXU HXU proposed FACET-II LCLS-I LCLS-II SC Linac cross-over bypass line m-wall A-line B-line Sector-10 Sector-20 Sector-30 Sector-0 extension line L3 L2 L1 s (m)

new linac beam axis defined X= +0.28 m , Y= -0.99 m w.r.t. original linac axis Z= original linac Z-coordinate Z= 0 at start of LI01 Z= -20 m at cathode

LCLS-II - Linac and Compressor Layout for 4 GeV Cavities per Amplifier j = * V0 =94 MV Ipk = 12 A Lb = 2.0 mm L1 j =-21° V0 =223 MV Ipk = 12 A Lb =2.0 mm L2 j = -21° V0 =1447 MV Ipk = 50 A Lb = 0.56 mm L3 j = 0 V0 =2409 MV Ipk = 1.0 kA Lb = 0.024 mm HL j =-165° V0 =55 MV CM01 CM2,3 3.9GHz CM04 CM15 CM16 CM35 LTU E = 4.0 GeV R56 = 0 sd  0.016% 2-km LH E = 95 MeV R56 = -14.5 mm sd = 0.05 % BC1 E = 250 MeV R56 = -55 mm sd = 1.4 % BC2 E = 1600 MeV R56 = -60 mm sd = 0.46 % GUN 0.75 MeV 100-pC machine layout: Oct. 8, 2013; v21 ASTRA run; Bunch length Lb is FWHM Linac Sec. V (MV) j (deg) Acc. Grad. (MV/m) No. Cryo Mod’s No. Avail. Cav’s Spare Cav’s Cavities per Amplifier L0 94 * 13.2 1 8 L1 220 -21 14.3 2 16 HL -55 -165 14.5 3 12 L2 1447 15.5 96 6 48 L3 2409 15.4 20 160 10 Includes 2-km RW-wake * L0 cav. phases: ~(3.4, -15.2, 0, 0, 0, 15, 15), with cav-2 at 22% of other L0 cavity gradients.

Gun + L0 Egun = 750 KeV Einj = 98 MeV L0 : α = -0.2173 Egun = 750 KeV Einj = 98 MeV L0 : 8 cavity cryomodule (layout courtesy XFEL Mad deck) gradients and phases per P. Emma layout (version of October 8, 2013) initial Twiss are “artificial” final Twiss from C. Papadopoulos ("GUN2013_10_08v3“)

Matching + Laser Heater + L1 98 MeV 250 MeV Einj = 98 MeV EBC1 = 250 MeV 6 quadrupole matching section between L0 and Laser Heater Laser Heater chicane: lengthened version of LCLS system (L= 3.529 m) ηmax= 7.5 cm, R56= 14.5 mm βX = βY = 10 m (α = 0) at center of chicane includes momentum collimator space for kicker (L= 2 m) and long drift (L= 8 m) provided for extraction to diagnostic line L1 : 2 x 8 cavity cryomodules (layout courtesy XFEL Mad deck) … φ= -22° 3 x 4 cavity harmonic linearizer cryomodules (3.9 GHz) … φ= -165° 90° FODO lattice

BC1 + Betatron Collimation EBC1 = 250 MeV BC1 chicane : copy of LCLS system R56= 55 mm small βX at fourth bend (CSR) space for kicker (L= 2 m) and long drift (≈ 15 m total) provided for extraction to diagnostic line betatron collimation system : 2 x 90 ° FODO cells (Lcell ≈ 16 m) β = 25 m at collimators (2 x horizontal collimation + 2 x vertical collimation)

L2 250 MeV 1.6 GeV EBC1 = 250 MeV EBC2 = 1.6 GeV L2 : 12 x 8 cavity cryomodules (layout courtesy XFEL Mad deck) … φ= -21° 30° FODO lattice

BC2 + Betatron Collimation EBC2 = 1.6 GeV BC2 chicane : copy of LCLS system R56= 60 mm small βX at fourth bend (CSR) space for kicker (L= 2.5 m) and long drift (≈ 30 m total) provided for extraction to diagnostic line betatron collimation system : 2 x 90 ° FODO cells (Lcell ≈ 24 m) β = 38.4 m at collimators (2 x horizontal collimation + 2 x vertical collimation)

L3 + Extension to LI10 EBC2 = 1.6 GeV Efinal = 4.0 GeV L3 : 20 x 8 cavity cryomodules (layout courtesy XFEL Mad deck) … φ= 0 15° FODO lattice L3 extension : 4 x 90° FODO cells (Lcell= 45 m) at start of Bypass Dogleg, Z= 936.872 m (≈ 22.5 m into LI10)

Bypass Dogleg + Match to Bypass Line FODO Efinal = 4.0 GeV dogleg bending system : from X/Y = +0.28/-0.99 m to X/Y = -0.650494/+0.649478 m (ΔX/ΔY = -0.37/+1.64 m) two 1.06° bends, rolled to 60.4° 4 x 90° FODO cells (Lcell= 25.4) cancel dispersion in both planes momentum collimator and wire scanner included total Z-length = 102.5 m

To Do for “Baseline” release update compression parameters to latest version of P. Emma layout use M. Venturini’s laser heater undulator parameters exchange X and Y collimators in HXR diagnostics section upload files to SharePoint site MAD8 input files MAD8 output files ELEGANT input files generate upload files for Oracle Database To Do after “Baseline” release reduce chromaticity of initial matching section (L0 to LH) and other sections identified by Paul design extraction systems and diagnostic lines (LH, BC1, BC2) more relaxed β-functions in L2 and L3 (FFODDO rather than FODO?) add correctors, BPMs, and other diagnostics more …

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