Kicker Optics – or – Selected ATF-II EXT Line Performance Issues ATF-II Technical Review, April 3 2013M. Woodley1/40.

M. Woodley

Kicker Optics– or –

Selected ATF-II EXT LinePerformance Issues

ATF-II Technical Review, April 3 2013 1/40

M. WoodleyATF-II Technical Review, April 3 2013 2/40

emittancemeasurement

couplingcorrection inflector extraction

e-

septa(BS1X,BS2X,BS3X)

kicker(KEX1)

Linac

Damping Ring

Final Focus

6 m

EXT

kicker(KEX2)


• EXT optics• vertical dispersion correction• emittance measurement in EXT

– stability– emittance growth (DR to EXT)– bunch charge dependence

• coupling correction• beta matching• extraction kicker

– multipole components (simulation and beam-based measurements)• QM7R replacement• BS3X rotation• extraction kicker (2)

– strength calibration– rotation

• BS3X skew field• Summary

Outline


Optics• most inflector magnets at the same phase … corrections within the

inflector correct errors that originate in the inflector (single-phase corrections)

• two skew quadrupoles are included in the inflector for vertical dispersion correction– “sum” mode (Σ-knob) generates vertical dispersion (no coupling)– “difference” mode (Δ-knob) generates coupling (no vertical dispersion)

• coupling correction section is standard ILC orthonormal system (four skew quadrupoles)

• emittance diagnostic section is a compromise due to space limitations … 2D reconstruction with beam tilts from 4 OTRs


0

10

20

1/2

XY

-0.75-0.5

-0.250

0.250.5

0.75

0 5 10 15 20-1

0

1

S (m)

KE

X1

BS

1X

BS

2X

BS

3X

BH

1X

BH

2X

BH

3X

KE

X2

QM

6R

QM

7R

QF

1X

QD

2X

QF

3X

QF

4X

QD

5X

QF

6X

QF

7X

QD

8X

Extraction + Inflector

0

100

200

Be

ta (

m)

XY

-360

-180

0

180

360

(

de

g)

0 5 10 15 20

-0.5

0

0.5

Eta

(m

)

S (m)

QS1X QS2X


25 30 35 40 45 500

2

4

6

8

10

12

14

16

18

20

Be

ta (

m)

S (m)

EXT Coupling Correction / Emittance Diagnostic Section

SQ SQ WS WS WS WS WS

90°90°

180°90°

90°90°

– x– y

8°20°

39°28°

32°46°

112.58.5

146.07.2

90.811.4

141.119.4σ (μm)

SQ SQ

OTR OTR OTR OTR

Δψ

ILC “orthonormal”coupling correction

system

xy

x’y’

x’y

xy’

InflectorFinalFocus


Vertical Dispersion Correction

• best emittance measurements when ηy at OTRs is small (millimeter-ish)

• can’t correct ηy at EXT OTRs (IP-phase) and in FF (FD-phase) simultaneously using the QS Σ-knob

• presence of KEX2 prevented use of vertical dipole correctors for ηy correction– emittance growth due to sextupole component

when off axis vertically – KEX2 is now gone (using BKX dipole instead) …

more later• now use both QS Σ-knob and vertical dipole

correctors for vertical dispersion correction• see Okugi-san’s talk this afternoon for updates …

IP-phase

FD-phase

M. Woodley

140 150 160 170 180 190 200 210 220-5000

-4000

-3000

-2000

-1000

0

1000

2000

3000

4000

Orb

it (u

m)

S (m)

ZV3X: ΔI = +0.096 A

140 150 160 170 180 190 200 210 220-250

-200

-150

-100

-50

0

50

100

150

200

250

DY

(m

m)

S (m)

ZV3X: ΔI = +0.096 A

140 150 160 170 180 190 200 210 220-5000

-4000

-3000

-2000

-1000

0

1000

2000

3000

4000

Orb

it (u

m)

S (m)

ZV11X: ΔI = +0.049 A

140 150 160 170 180 190 200 210 220-250

-200

-150

-100

-50

0

50

100

150

200

250

DY

(m

m)

S (m)

ZV11X: ΔI = +0.049 A


Simulation

M. Woodley

Monday Day Shift, December 17, 2012

after QS Σ-knob only FD-phase correction after QS Σ-knob + ZV correction

QS*X : -1.050 A -0.113 A (ΔI = +0.937 A) … correct IP-phase ηy

ZV3X : +0.172 A +0.047 A (ΔI = -0.125 A) … correct FD-phase ηy

ZV11X : +0.201 A +0.229 A (ΔI = +0.028 A) … correct FF orbit



EXT Emittance Measurements• do we believe the OTR measurements?• how stable/reproducible are the measurements?• observations (DR XSR and EXT multi-OTR)

– charge dependence


OTR Vertical EmittanceMeasurement

December 14, 2011 07:44

Wire Scanner MeasuredVertical Beam SizesDecember 14, 2011 09:30(MW1X σy value ignored)

QF

9X

QK

1X

Q

D10

X

QF

11X

QK

2X

Q

D12

X

QF

13X

QD

14X

QF

15X

QK

3X

Q

D16

X

QF

17X

QK

4X

QD

18X

QF

19X

QD

20X

QF

21X

EXT Diagnostics Section

165 170 175 180 185 1900

5

10

15

20

25

30

35

40

Ver

tical

Bea

m S

ize

(um

)

S (m)

black circles = WS (4): εy = 43 ± 3 pmblue circles = OTR (4): εy = 50 ± 4 pm

Wire Scanner / OTR Comparison


250 300 350 400 450 500 550 600 650 700250

300

350

400

450

500

550

600

650

700

750OTR2X X VS ZH9X Expected Pos

ZH9X Expected Pos /um

OT

R2X

X /

um

p0= 8.922+- 8.079p1= 0.9918+-0.01692

RMS= 7.75 umNDF= 9

chisq/N = 1.081rho = 1.010

OTR2X beam tilt … is the beam rotated? Check measured response to ZH9X

X

Y

OTR0X before corrections OTR0X after dispersion correction OTR0X after coupling correction


0 1 2 3 4 5 6 7 8 9 10 1120

21

22

23

24

25

26

27

28

29EmitY = 25.4122 +- 0.2439 pm

Em

itY (

pm)

Meas #0 1 2 3 4 5 6 7 8 9 10 11

0.2

0.25

0.3

0.35

0.4

0.45

0.5

0.55

0.6

0.65ICT = 0.4967 +- 0.0082

ICT

Meas #

Stability: 10 Consecutive EXT Emittance Measurements (November 29, 2012 … ~30 minutes)

0 1 2 3 4 5 6 7 8 9 10 1123

23.5

24

24.5

25

25.5

26

26.5

27

ICT

Cor

rect

ed E

mitY

(pm

)

Meas #

EmitY = 25.2738 +- 0.1437 pm @ ICT = 0.45 (chisq=1)

0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.6520

21

22

23

24

25

26

27

28

29

30EmitY vs ICT

ICT (e10)

Em

itY (

pm)

p0= 16.4+- 1.261

p1= 19.73+- 2.707

RMS= 0.42 pm

NDF= 8 chisq/N = 0.391

rho = 1.001

EmitY = 16.4 ± 1.3 pm @ ICT = 0ΔEmitY/ΔICT ≈ 2 pm/109


earthquake3.11.2011

ILC DR: εy = 20 nm

ILC IP: εy = 35 nm

ATF-II: εy = 30 nm

Emittance: 2011 – 2012(S. Kuroda)

~2.5 pm / 109

March 12, 2013 (XSR)March 12, 2013 (OTR; QS Δ-knob; QKs off)March 15, 2013 (OTR; QS Δ-knob; QKs off)

ATF-II: εy = 30 nm

Emittance: March 2013(K. Kubo, T. Okugi)

EATF-II = 1.28 GeVK. Kubo


DR XSR σy vs ICT

Δεy/ΔICT ≈ 0.6 pm / 1e9

ICT (1010)

DR

XSR

σ y (μm

)

November 6, 2012 Owl Shift

XSR source-point βy measurement

βy = 2.56 m


Coupling Correction• given installed emittance diagnostic section, is measurement and

correction of arbitrary phases of input coupling possible?• recently (February 2013) Okugi-san had success correcting

coupling at OTRs using QS1X/QS2X difference knob … see his talk this afternoon


• assume matched DR beam with εy = 12 pm• add coupling at many random phases … projected εy = 100 pm• correct projected εy two ways

– use 4 skew quadrupoles (QKs) to correct measured beam tilt at each OTR using a modeled response matrix– (effectively) scan 4 QKs to minimize projected εy (proposed ILC method)

E. Marin


Beta Matching• 6 dedicated β-matching quadrupoles are provided at the start of

the Final Focus, but they are downstream of the EXT OTRs– used for changing β*

• β-matching now being done with EXT quadrupoles, upstream of the OTRs … beta match can easily be verified

M. Woodley

name match0 match1 match2 match3 design

file 054152 061717 080625 084346

EmitX 1.7894 1.8228 1.7587 1.5860

BmagX 1.1946 1.0013 1.0026 1.0076 1.0000

EmBmX 2.1376 1.8251 1.7633 1.5981

BetaX 4.7239 6.0386 6.4327 6.2257 6.3052

AlphaX -2.8890 -4.2795 -4.6550 -4.5596 -4.4943

EmitY 28.4846 25.7572 30.8175 28.2300

BmagY 1.2000 1.3489 1.0554 1.0034 1.0000

EmBmY 34.1808 34.7439 32.5253 28.3262

BetaY 9.1308 9.4923 7.1151 6.0766 6.1903

AlphaY 4.4037 4.8369 3.2854 2.6087 2.5763

QF1X 50.682 50.947 50.812 50.812 49.024

QD2X 42.865 43.035 43.312 43.312 42.865

QF3X 30.497 30.724 30.800 30.800 30.498

QF4X 30.863 30.710 30.636 30.636 30.864

QD5X 41.940 42.083 41.995 41.995 41.940

QF6X 52.983 52.753 52.692 52.692 51.556

QF7X 54.600 54.524 57.931 57.931 54.601

QD8X 26.862 26.850 27.005 27.005 26.863

QF9X 34.701 36.133 36.027 36.027 34.702

QD10X 52.965 51.764 56.860 56.860 52.964


Beta Matching (December 12 2012 owl)

0

1

2

3

X Y


Extraction Kicker• multipole fields (quadrupole/sextupole): are they real?• 2nd kicker (KEX2) removed from beamline and replaced with a

strong dipole corrector in January 2012


POISSON Field Simulation (C. Pappas, SLAC)

1 2 3 4

0.75" Ф0.827" Ф

0.5"0.75" 1.3"1.0"

0.0625"

0.591" Ф

electrodeceramicchamber

scale: 1.14" (figure) ≈ 0.75" (actual)

±25σx

ceramic chamber

DIMAD SBEND parameters:

L = 0.4 m ANGLE = 5.0e-3 rad K1 = -1.846929e-1 m-2

K2 = -3.824591e+1 m-3

M. Woodley

0 10 20 30 40 50 60-5

-4

-3

-2

-1

0

1

2

3

4

5

X

(m

m)

S (m)

KE

X1

QM

6RQ

M7R

BS

1XB

S2X

BS

3X

BH

1X

BH

2X

BH

3X

KE

X2

QS

1X

Q

F1X

QD

2X

Q

F3X

QF

4X

Q

D5X

QF

6X

Q

S2X

QF

7X

QD

8X

QF

9X

QK

1X

Q

D10

X

Q

F11

X

Q

K2X

QD

12X

QF

13X

QD

14X

QF

15X

QK

3X

Q

D16

X

Q

F17

X

Q

K4X

QD

18X

QF

19X

QD

20X

QF

21X

QM

16F

F

Q

M15

FF

QM

14F

F

Q

M13

FF

QM

12F

F

Q

M11

FF

QD

10B

FF

Q

D10

AF

F

QF

9BF

F

Q

F9A

FF

QD

8FF

QF

7FF

SF

6FF

0 10 20 30 40 50 60-5

-4

-3

-2

-1

0

1

2

3

4

5

Y

(m

m)

S (m)

KE

X1

QM

6RQ

M7R

BS

1XB

S2X

BS

3X

BH

1X

BH

2X

BH

3X

KE

X2

QS

1X

Q

F1X

QD

2X

Q

F3X

QF

4X

Q

D5X

QF

6X

Q

S2X

QF

7X

QD

8X

QF

9X

QK

1X

Q

D10

X

Q

F11

X

Q

K2X

QD

12X

QF

13X

QD

14X

QF

15X

QK

3X

Q

D16

X

Q

F17

X

Q

K4X

QD

18X

QF

19X

QD

20X

QF

21X

QM

16F

F

Q

M15

FF

QM

14F

F

Q

M13

FF

QM

12F

F

Q

M11

FF

QD

10B

FF

Q

D10

AF

F

QF

9BF

F

Q

F9A

FF

QD

8FF

QF

7FF

SF

6FF

what we expected to see (no kicker multipoles) …

bad BPMs

… what we observed


Orbit Bump Study (February 2010): bump vertically through KEX2

bad BPMs

M. Woodley

what we expected to see (with predicted kicker multipoles) …

… what we observed

0 10 20 30 40 50 60-5

-4

-3

-2

-1

0

1

2

3

4

5

Y

(m

m)

S (m)

KE

X1

QM

6RQ

M7R

BS

1XB

S2X

BS

3X

BH

1X

BH

2X

BH

3X

KE

X2

QS

1X

Q

F1X

QD

2X

Q

F3X

QF

4X

Q

D5X

QF

6X

Q

S2X

QF

7X

QD

8X

QF

9X

QK

1X

Q

D10

X

Q

F11

X

Q

K2X

QD

12X

QF

13X

QD

14X

QF

15X

QK

3X

Q

D16

X

Q

F17

X

Q

K4X

QD

18X

QF

19X

QD

20X

QF

21X

QM

16F

F

Q

M15

FF

QM

14F

F

Q

M13

FF

QM

12F

F

Q

M11

FF

QD

10B

FF

Q

D10

AF

F

QF

9BF

F

Q

F9A

FF

QD

8FF

QF

7FF

SF

6FF

0 10 20 30 40 50 60-4

-3

-2

-1

0

1

2

3

4

X

(m

m)

S (m)

KE

X1

QM

6RQ

M7R

BS

1XB

S2X

BS

3X

BH

1X

BH

2X

BH

3X

KE

X2

QS

1X

Q

F1X

QD

2X

Q

F3X

QF

4X

Q

D5X

QF

6X

Q

S2X

QF

7X

QD

8X

QF

9X

QK

1X

Q

D10

X

Q

F11

X

Q

K2X

QD

12X

QF

13X

QD

14X

QF

15X

QK

3X

Q

D16

X

Q

F17

X

Q

K4X

QD

18X

QF

19X

QD

20X

QF

21X

QM

16F

F

Q

M15

FF

QM

14F

F

Q

M13

FF

QM

12F

F

Q

M11

FF

QD

10B

FF

Q

D10

AF

F

QF

9BF

F

Q

F9A

FF

QD

8FF

QF

7FF

SF

6FF

bad BPMs


Orbit Bump Study (February 2010): bump vertically through KEX2

M. Woodley

set ZH3X/ZH4X/ZH5X X-bump; scan ZV5X/ZV6X/ZV7X Y-bump; find X-bump setting where Y-bump closes

at this point the quadrupole field seen by the beam in KEX2 has the value predicted by POISSON for the vacuum chamber center

ΔX ΔY

ΔX = +3 mm

ΔX = +1 mm

ΔX = 0

ΔX = -1.5 mm



Δεy/εy0 (%) ≈ 60.4 × [ΔYkicker1 (mm)]2

Predicted Vertical Emittance Growth(ηy corrected)

15 pm -> 24 pm @ +- 1 mm

Horizontal Jitter

Vertical Jitter

KEX2 removed January 2012


QM7R Replacement• original quadrupole (Tokin 3393) had 16 mm pole-tip radius• extracting beam passed through at 22.5 mm … in the coil pocket• PRIAM simulations (P. Bambade) predicted large sextupole

component at extracting trajectory• QM7R replaced (January 2009) … new quadrupole (Tokin 3581) has

21 mm pole-tip radius– sextupole strength (K2L) reduced from 47 m-2 to 1 m-2


QM7R: pole-tip radius = 16 mm … extracted beam offset = 22.5 mm

Tokin 3393 (Ф = 32 mm)


K1L

K0L

K2L

QM7R replaced with larger bore (Ф = 42 mm) quadrupole in January 2009

K1L = 0.3 m-1 = 0.76 nominal optics mismatch

K2L = 46.6 m-2

x-y coupling for vertically off-axis beam: factor ~ 2-3 × y for y = 1 mm (εx:εy = 100:1)

Tokin 3393 (Ф = 32 mm)

PRIAM simulation

K1L = 0.392 m-1 = 0.99 × nominal K2L = 1 m-2

Tokin 3581 (Ф = 42 mm)

Measured


BS3X Rotation• origin of strong vertical corrector ZV1X at beginning of EXT line

and observed anomalous vertical dispersion in EXT/FF?– measured vertical dispersion in DR at extraction point is

normally small• 3rd septum magnet BS3X thougth to be kicking vertically• BS3X was physically rolled ~ -4 mrad on March 17, 2010• vertical orbit and measured εy improved


0 2 4 6 8 10 12 14-1.2

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

Y

(m

m)

S (m)

KE

X1

QM

6R

QM

7R

BS

1X

BS

2X

BS

3X

BH

1X

QS

1X

Q

F1X

QD

2X

QF

3X

ZV

100R

X

ZV

1X

ZV

2X

ZV

3X

BS3X roll = 4.66 mrad

BS3X roll = 4.66 mradIzv1 = -6.918 (-6.976) ampIzv2 = 1.270 ( 0.965) ampchi2 = 0.3102

Observed that first 2 EXT vertical correctors (ZV1X and ZV2X) needed to be strong to properly launch into EXT (since before EXT rebuild for ATF2 … )

• hypothesize that correctors are compensating for a kick error in extraction channel• simulate error kick by rolling individual elements; use ZV1X and ZV2X to correct orbit• find error that gives best fit to actual ZV1X/ZV2X values → BS3X septum magnet roll• BS3X was physically rolled ~ -4 mrad (March 17, 2010) to relieve ZV1X and ZV2X• projected vertical emittance in EXT before coupling correction was improved

(~20-40 pm before → ~10-20 pm after)

-9 -8 -7 -6 -5 -4 -3 -2 -1 0 1-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

1.2

1.4SET-file values (April 2009 - May 2010)

ZV

2X C

urre

nt (

A)

ZV1X Current (A)

before March 17, 2010

after March 17, 2010


Extraction Kicker (2)• kicker strength setpoint (voltage) has been creeping up• beam-based calibration measurement• vertical steering … rotation

2010 2011 2012 201335

40

45

50

Time

EX

T-D

KIC

KE

R (

kV)

DR Extraction Kicker Historic Setpoint Data (from SET-files)

M. Woodley

-800 -700 -600 -500 -400 -300 -200 -100 00

50

100

150

200

250

300

350

400

450dX/dV = -0.5085 um/V

X BS

3X (

um)

KEX (V)

V

x

RcVcRx

1212

1,,

R12 = 4.7329 mm/mraddX/dV = -0.5085 mm/kV

dθ/dV = -0.1074 mrad/kVθ0 = -5 mrad V0 = 46.5 kV

(SLAC NDR KEX: 0.1158 mrad/kV)

Horizontal orbit position at BS3X center estimated by

back-propagation from EXT BPM measurements

(QF1X-QF4X) … courtesy of Yves Renier

8 μm

112 μm

215 μm

315 μm

415 μm

0 V

-200 V

-400 V

-600 V

-800 V

ΔX @ BS3X (from orbit fit) ΔVKEXΔX

ATF2 feedback

measurement: 2012/12/07 Owl Shift



40 45 501520

1540

1560

1580

1600

BS

1X (

A)

KEX (kV)40 45 50

2540

2560

2580

2600

BS

3X (

A)

KEX (kV)

40 45 50-1.5

-1

-0.5

0

0.5

ZV

1X (

A)

KEX (kV)40 45 50

-0.4

-0.2

0

0.2

0.4

ZV

2X (

A)

KEX (kV)

EXT Orbit (Corrected) vs KEX VoltageDecember 13, 2012 Day Shift

(Okugi)


KEX1 Roll ≈ -85 mrad (-5° !)

40 45 50-20

0

20

40BS1X/BS2X

I (

A)

measuredsimulated

40 45 50-30

-20

-10

0

10

20BS3X

I (

A)

40 45 50-1

-0.5

0

0.5ZV1X

I (

A)

VKEX1

(kV)40 45 50

-0.2

-0.1

0

0.1

0.2

0.3ZV2X

I (

A)

VKEX1

(kV)

+6 A

-1.7 A


BS3X Skew Field• observed anomalous vertical dispersion in EXT/FF

– measured vertical dispersion in DR at extraction point is small– well modeled with a skew quadrupole field at BS3X septum

• we have had problems with BS3X in the past– BS3X had to be physically rolled ~ -4 mrad (March 17, 2010)

• measured dependence of inferred skew quadrupole strength versus horizontal position in BS3X is consistent with a skew sextupole field with: K2L = 16 m-2

– our strongest FF sextupole (SD4FF) has K2L = 14.91 m-2

M. Woodley

140 150 160 170 180 190 200 210 220 230

-600

-400

-200

0

200

400

600

DY

(m

m)

S (m)

Modeledηy0 = -13.2 mmη′y0 = -14.2 mr

140 150 160 170 180 190 200 210 220 230

-600

-400

-200

0

200

400

600

DY

(m

m)

S (m)

ModeledBS3X skew quad

KL = -0.03 m-1

(IIDX = -5.8 A)

12 pm 39 pm

Measured

Δμy(BS3XIP) = 101.8°


NOTE: ηx = 179 mm @ BS3X

BS3X

M. Woodley

0 50 100 150 200 250 300 350 400 450-0.036

-0.034

-0.032

-0.03

-0.028

-0.026

-0.024BS3X Skew KL vs BS3X X Position

KL

(1/m

)

X (um)-800 -700 -600 -500 -400 -300 -200 -100 0

-0.036

-0.034

-0.032

-0.03

-0.028

-0.026

-0.024BS3X Skew KL vs Kicker Voltage

KL

(1/m

)

KEX (V)

ΔKEX = -800 V KLBS3Xskew = -0.02610 m-1

140 150 160 170 180 190 200 210 220-800

-600

-400

-200

0

200

400

600

DY

(m

m)

S (m)

Measured Modeled


BS3Xskew = 0 @ KEX = 46.7 kV

KEX lower voltage

BS3Xskew = 0 @ BS3X X = +1.7 mm

toward DR (to the left)

skew sextupoleK2L = 16 m-2


49.1 49.2 49.3 49.4 49.5 49.6 49.7 49.8 49.9 50 50.1350

400

450

500

550

600V0 = 46.519 +- 0.046 (kV)

|DY

| (um

)

EXT_DKICKER (kV)

QD10B

QD4A

Dec 7 (KEX @ 50 kV)

45.5 45.6 45.7 45.8 45.9 46 46.1 46.2 46.3 46.4 46.5350

400

450

500

550

600V0 = 45.784 +- 0.360

|DY

| (um

)

EXT_DKICKER (kV)

QD10B

QD4A

Dec 12 (KEX @ 46 kV)

Set EXT Kicker Voltage to 46 kV


http://atf.kek.jp/twiki/pub/ATFlogbook/Meeting201307/EXT_misalignments_Study.pdf

Study by Edu Marin (March 2013)

M. WoodleyATF-II Technical Review, April 3 2013

Summary• EXT optics is well understood and capable of delivering matched and dispersion-corrected beams to

the Final Focus– there are some remaining anomalies in the DR extraction channel– still looking for sources of emittance growth (and its current dependence)

• multi-OTR EXT emittance measurements are reliable and stable– measured beam tilt (coupling) values are believable and correspond to real X-Y coupling– direct beam tilt correction using a modeled response matrix looks like a superior coupling correction technique

• extracted vertical emittance is strongly dependent on bunch charge– 2-3 pm per 109 … much larger than observed in DR– weaker dependence observed recently? … see Okugi-san’s talk this afternoon

• extraction magnets (kicker, QM7R, septa) have been problematic, but improvements are being made• observed KEX1 quadrupole/sextupole field components agree with POISSON field simulation

– tracking simulations indicate that vertical beam offset in KEX1 is not a source of significant emittance growth– removing 2nd kicker gave us more tuning flexibility, without significantly increasing beam jitter

• roll alignment of bending magnets has been problematic, but improvements are being made• some mysteries remain

– is KEX1 rolled? by how much? can it be fixed?– are there anomalous magnetic fields in BS3X, or are other errors fooling us?– if there are anomalous magnetic fields in BS3X, can the magnet be fixed?

• can Okugi-san’s QS Δ-knob coupling correction technique tell us more about any coupling sources?

40/40

Kicker Optics – or – Selected ATF-II EXT Line Performance Issues ATF-II Technical Review, April 3 2013M. Woodley1/40.

Documents

technical review

phase zv3x

ext otrs ipphase

correct ipphase yzv3x

ff fdphase

correct fdphase yzv11x

inflector correct errors

otrs atf