LCLS-II β-Matching Study based on 29JUN16 optics sqrt(3) > α > -sqrt(3) 2+sqrt(3) > β > 2-sqrt(3)

LCLS-I (diag. not shown) Nov. 28, 2016 28NOV16 LCLS-II e- Beam Diagnostics (Baseline & Deferred) Not included: BPMs, Charge Monitors, X-ray diagnostics DS-SX m-wall OTRDMPb SXU WSEMIT2 OTRDL18 DS-DL YAGXRAYb BC1 BZ21b LH WSVM2 WS31b WS32b WS33b WS34b TCX01b Proposed FACET-II LCLS-I (diag. not shown) L2 L3 Sec. 11-20 Linac Sec. 21-30 Linac DS-HX DL OTRDMP OTR21b WS21 BYPASS WS31 WS32 WS33 WS34 OTRDOG WSDL31 WSDOG OTR31 WSBP1 WSBP2 WSBP3 WSBP4 YAGXRAY BC2 OTRSPDMP WSSP1D OTR30 HXU DS-BP WSDL4 OTR33 TCX01 OTR33 2 HTR CM02 CM03 BC1 L1 Wire-Scanner OTR Screen YAG Screen Bunch Length DS-H DS-1 DS-D CM01 Gun 3.9 WS0H04 WSC006 YAGH1 YAGH2 TCXDG0 OTRDG02 OTRDG01 OTRDG03 OTRDG04 WSDG01 YAG01 WS11 OTR11b WSC104 WSC106 WSC108 WSC110 BZ11b BZC1 OTR0H04 OTRC006 BZ0H04 DS-L1 TCYDG0

LCLS-II Measurement and Correction Stations Location Diag. Station Measures Type Diag. Names Correctors Beam to… Pre-Heater DS-H ex,y, bx,y, ax,y proj WS0H04 Q0H01,2,3,4 INJ Dump Heater sx, sy, <x>, <y> YAGH1, 2 IR laser mirrors & focusing Post-Heater DS-D proj/slice WSDG01, OTRDG02, 1, 3 QHD01,2,3,4 Pre-L1 DS-L1 OTRC006, WSC006 QC001,2,3,4,5 CEBC1 ? BC1 DS-1 sd OTR11b, WS11 L1 phase/volt CEBC2 ? WSC104, 06, 08, 10 QCM03, Q1C01, QC101,2,3,4 BC2 DS-2 OTR21b, WS21 L2 phase/volt BSY dump WSEMIT2 QCM14,15, Q2C01, QE201,2 sz - XTCAV ? HXR dump Dog-Leg-1 DS-DL OTRDOG, WSDOG L3 phase/volt Bypass DS-BP WSBP0, 1, 2, 3 QL1P,2P,3P,4P,5P SXR Trans DS-SX WS31b, 2b, 3b, 4b QEM1b,2b,3b,4b SXR dump OTRDL18 Dechirper? HXR Trans DS-HX WS31, 2, 3, 4 QEM1,2,3,4 OTR30, WSDL31 SXR und/dmp blind QUM1b,2b,3b,4b/QSXH47, QUE1b,2b,QDMP1b-2b HXR und/dmp QUM1,2,3,4/QHXH46, QUE1,2, QDMP1,2

Pre-Heater: L0 to INJ ε

WS0H04 LH mid COL0/ DIAG0 GUNB

Quad-scan emittance measurement (εx,y = 0.5 μm)

100% E = 100 MeV seedQ=true match at INJ WS0H04 (GLmax: 20 kG (cryo), 6 kG (2Q4)) BMAG=2 100% matched

INJ ε to LH blind match

Quad-scan emittance measurement (εy = 0.5 μm) No horizontal measurement due to dispersion

E = 100 MeV 30% seedQ=true E = 100 MeV 67% seedQ=false

Post-Heater: LH to DIAG0 ε

WSDG01 INJ FCDG0DU

Quad-scan emittance measurement (εx,y = 0.5 μm)

100% E = 100 MeV seedQ=true match at DIAG0 WSDG01 (GLmax: 6 kG (2Q4)) BMAG=1.5 100% matched

Pre-L1: LH to COL0 ε

WSC006 DIAG0 L1 Should wire scanner (WSC006) be centered between QC006 and QC007?

Quad-scan emittance measurement (εx,y = 0.5 μm)

60% 95% E = 100 MeV seedQ=true E = 100 MeV seedQ=true match at COL0 WSC006 with 4 quads (GLmax: 16 kG (1.259Q3.5)) BMAG=1.5 all quads bipolar 60% matched 95% E = 100 MeV seedQ=true

COL0 QC001 QC002 QC003 QC004 QC005 BKRDG01 BLRDG01 DIAG0

not including CSR waist at BCX14 BC1: L1 to COL1 ε not including CSR waist at BCX14

WSC104 WSC106 WSC108 WSC110 L1 L2

Quad-scan emittance measurement (εx,y = 0.5 μm)

E = 250 MeV 48% seedQ=false 93% E = 250 MeV seedQ=true

including CSR waist at BCX14 BC1: L1 to COL1 ε including CSR waist at BCX14

99% E = 250 MeV seedQ=true 100% E = 250 MeV seedQ=true

not including CSR waist at BCX24 BC2: L2 to EMIT2 ε not including CSR waist at BCX24

WSEMIT2 L2 L3

Quad-scan emittance measurement (εx,y = 0.5 μm, E = 2 GeV) requires 15 A Quad-scan emittance measurement (εx,y = 0.5 μm, E = 2 GeV)

68% E = 2.0 GeV seedQ=true 68% E = 2.0 GeV seedQ=false

94% E = 2.0 GeV seedQ=true 100% E = 2.0 GeV seedQ=false

including CSR waist at BCX24 BC2: L2 to EMIT2 ε including CSR waist at BCX24

93% E = 2.0 GeV seedQ=true 96% E = 2.0 GeV seedQ=false

Bypass: Dogleg to BYP ε

WSBP0 EXT BYP

93% 100% E = 10.0 GeV seedQ=true rearrange quads E = 10.0 GeV

SXR Trans: LTUS to LTUS ε

WS31B WS32B WS33B WS34B UND match LTUS

82% E = 10.0 GeV seedQ=true 99% E = 10.0 GeV seedQ=true

HXR Trans: LTUH to LTUH ε

WS31 WS32 WS33 WS34 UND match LTUH

96% E = 10.0 GeV seedQ=true

Summary (1) injector quad scan εx,y measurement OK Q0H02 on WS0H04 matching injector (L0 output) is 100% OK up to BMAG=2 Laser Heater quad scan εy measurement OK Q0H08 on YAGH1 or YAGH2 matching Laser Heater waist has limited range (but not needed) DIAG0 quad scan εx,y measurement OK QHD04 on WSDG01 matching into DIAG0 line is 100% OK up to BMAG=1.5 COL0 quad scan εx,y measurement OK QC004 on WSC006 matching into COL0 is 94% OK up to BMAG=1.5, given: 5 quadrupoles (QC001-5) all quads bipolar COL1 quad scan εx,y measurement OK QC104 on WSC104 matching into COL1 (no BC1 CSR waist) is 93% OK up to BMAG=1.5, given: 5 quadrupoles (Q1C01,QC101-4) QC101-4 bipolar

Summary (2) matching into COL1 (with BC1 CSR waist) is 99% OK up to BMAG=1.5, given: 6 quadrupoles (QCM03,Q1C01,QC101-4) QC101-4 bipolar EMIT2 quad scan εx,y measurement OK QE202 on WSEMIT2 εx measurement requires 15 A matching into EMIT2 (no BC2 CSR waist) is 100% OK up to BMAG=1.5, given: 5 quadrupoles (QCM14-15,Q2C01,QE201-2) QCM14-15 bipolar matching into EMIT2 (with BC2 CSR waist) is 96% OK up to BMAG=1.5, given: QCM14-15, Q2C01 bipolar matching into BYP is 100% OK up to BMAG=1.5, given: 5 rearranged quadrupoles (QL1P-QL5P) all quads unipolar matching in LTUS is 99% OK up to BMAG=1.5, given: 5 quadrupoles (QVM4B, QEM1B-4B) QEM1B-QEM3B bipolar

Summary (3) matching in LTUH is 96% OK up to BMAG=1.5, given: 4 quadrupoles (QEM1-4) all quads unipolar

Issues BMAGx and BMAGy amplitudes always equal … try unequal amplitudes? ability to match sometimes depends on exact location of mismatch, even though all phases sampled … why? matching with more variables (quadrupoles) than constraints is sensitive to initial strengths of quads should wire scanner (WSC006) be centered between QC006 and QC007? quad-scan ε measurement in EMIT2 requires 15 A space charge effects during ε measurement and matching in injector at 100 MeV (send worst case to Ji for analysis) etc …

To Do unequal BMAGx and BMAGy amplitudes finer BMAGx and BMAGy phase increment with different locations for mismatch redo injector match with laser heater chicane and undulator off (YAGs not usable) check injector matching with 20/100/300 pC initial beams check quadrupole chromatic emittance dilution at each step check beam sizes in collimators at each step … how many sigma? move WSC006 to center between QC006 and QC007 try moving mismatch to beginning of dogleg in Bypass match rename Bypass wire scanners (1,2,3,4) etc …

“Magnets” PRD (LCLSII-2.4-PR-0081-R3) Quad Eng. Type GLMAX (kG) Polarity PS String QCM01 CRYO 20 B / B * Q0H01 2Q4 6 Q0H02 Q0H03 Q0H04 Q0H05 U / U Q0H06 Q0H07 Q0H08 QHD01 QHD02 QHD03 QHD04 QC001 1.26Q3.5 QC002 QC003 QC004 QC005 Quad Eng. Type GLMAX (kG) Polarity PS String QCM02 CRYO 20 B / B * QCM03 Q1C01 1.26Q3.5 QC101 QC102 QC103 QC104 QC105 QCM14 QCM15 Q2C01 QE201 QE202 25 QL1P* 2Q10 55 U / U QL2P* QL3P* 2Q4W 28 QL4P* QL5P * quadrupole locations changed w.r.t. 28NOV16

Quad Eng. Type GLMAX (kG) Polarity PS String QVM4B 1.26Q12 140 B / B * QEM1B 1.085Q4.31 100 QEM2B QEM3B QEM4B QEM1 ? / B QEM2 QEM3 QEM4