LCLS2sc MAD files: Injector to Bypass Linelattice version 1.2 (October 30, 2013)

M. Woodley

SXU

HXU

proposed FACET-II LCLS-ILCLS-II SC Linac

cross-overbypass linem-wall

A-line

B-lineSector-10 Sector-20 Sector-30Sector-0

extension lineL3L2L1

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

CM01 CM2,3 CM04 CM15 CM16 CM35BC1

E = 250 MeVR56 = -55 mmsd = 1.4 %

BC2E = 1600 MeVR56 = -60 mmsd = 0.46 %

GUN0.75 MeV

LHE = 95 MeV

R56 = -14.5 mmsd = 0.05 %

L0j = *

V0 =94 MVIpk = 12 A

Lb = 2.0 mm

L1j =-21°

V0 =223 MVIpk = 12 A

Lb =2.0 mm

HLj =-165°

V0 =55 MV

L2j = -21°

V0 =1447 MVIpk = 50 A

Lb = 0.56 mm

L3j = 0

V0 =2409 MVIpk = 1.0 kA

Lb = 0.024 mm

LTUE = 4.0 GeV

R56 = 0sd 0.016%

2-km

100-pC machine layout: Oct. 8, 2013; v21 ASTRA run; Bunch length Lb is FWHM

3.9GHz

LinacSec.

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 1 1

L1 220 -21 14.3 2 16 1 1

HL -55 -165 14.5 3 12 1 12

L2 1447 -21 15.5 12 96 6 48

L3 2409 0 15.4 20 160 10 48

* L0 cav. phases: ~(3.4, -15.2, 0, 0, 0, 15, 15), with cav-2 at 22% of other L0 cavity gradients.

Includes 2-km RW-wake

• 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“)

750 KeV

98 MeV

β = 7.5435 mα = -0.2173

Gun + L0

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

1.6 GeV

4.0 GeV

• 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

• 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 for “Baseline” release

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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