1 Zachary Wolfwolf@slac.stanford.edu

1Undulator Tuning StatusJune 9, 2009

Undulator Tuning Status

Z. Wolf, S. Anderson, R. Colon, S. Jansson, D. Jensen,

S. Kaplunenko, Y. Levashov, Ed. Reese, A. Weidemann

2 Zachary Wolfwolf@slac.stanford.edu

2Undulator Tuning StatusJune 9, 2009

Undulator Tuning Status

Overview• Status/Schedule • Reference Undulator• Undulator Repairs• Radiation Damage

3 Zachary Wolfwolf@slac.stanford.edu

3Undulator Tuning StatusJune 9, 2009

Re-Tuning

We are re-tuning all the undulatorsbecause of1) damage from temperature excursions2) beam pipe interferences

4 Zachary Wolfwolf@slac.stanford.edu

4Undulator Tuning StatusJune 9, 2009

Re-Tuning Schedule

28 undulators are in the tunnel5 undulators are still required2 undulators need repair6 spares need to be tunedK vs Temperature studies still need to be done

5 Zachary Wolfwolf@slac.stanford.edu

5Undulator Tuning StatusJune 9, 2009

Reference Undulator

X-Trajectory,Y-Trajectory, Phase vs Z,

Phase In Cell,all stable

Reference Undulatormeasured many times

6 Zachary Wolfwolf@slac.stanford.edu

6Undulator Tuning StatusJune 9, 2009

Reference Undulator

Field IntegralMeasurements,

Long Coil

Field integrals stable, but some systematic

changes

I1XvsX

I2XvsX

I1YvsX

I2YvsX

Reference Undulatornever tuned for

±6 mm goodfield region

7 Zachary Wolfwolf@slac.stanford.edu

7Undulator Tuning StatusJune 9, 2009

Reference UndulatorI1X vs Time

I2X vs Time

I1Y vs Time

I2Y vs Time

Field integralsat X=0

at differenttimes

Startedstraighteningcoil routinely,

improvedrepeatability

Field integralchanges possibly

due tocoil straightness

8 Zachary Wolfwolf@slac.stanford.edu

8Undulator Tuning StatusJune 9, 2009

Beam Axis Position

The beam axis position relative to the tooling balls is affected by many

errors.

The repeatability of the reference

undulator beam axis position is a measure of the rms error on K for the undulators in

the tunnel.

Reference Undulator

9 Zachary Wolfwolf@slac.stanford.edu

9Undulator Tuning StatusJune 9, 2009

Undulator Tooling Balls Relative To Beam Axis

Reference Undulator

10 Zachary Wolfwolf@slac.stanford.edu

10Undulator Tuning StatusJune 9, 2009

Change In Beam X Position Relative To X Tooling Balls

Reference Undulator

Average changedoesn’t affectperformance.

RMS change isimportant.

11 Zachary Wolfwolf@slac.stanford.edu

11Undulator Tuning StatusJune 9, 2009

Change In Beam Y Position Relative To Y Tooling Balls

Reference Undulator

12 Zachary Wolfwolf@slac.stanford.edu

12Undulator Tuning StatusJune 9, 2009

MMF Temperature History

Aside:The 9 degree temperature excursion in December 2008 caused a one month delay while we recalibrated, straightened the bench, and checked all the undulators in the MMF.

The smaller temperature excursions caused a one week delay each while we checked our calibrations.

Reference Undulator

13 Zachary Wolfwolf@slac.stanford.edu

13Undulator Tuning StatusJune 9, 2009

MMF Temperature Excursions T > 22 C

The large temperatureexcursions are notresponsible for the slope in the beam axis x-position plot.

deg C

Reference Undulator

14 Zachary Wolfwolf@slac.stanford.edu

14Undulator Tuning StatusJune 9, 2009

Hall Probe Calibrations

The hall probe wascalibrated several timesduring the tuning. Thechanges in x-position remained. Hall probe

calibration errors do notappear to be responsiblefor the change in beam

axis x-position.

Reference Undulator

15 Zachary Wolfwolf@slac.stanford.edu

15Undulator Tuning StatusJune 9, 2009

MMF Temperature Accuracy

deg C

Yurii compared our temperaturemeasurement system output to areference thermometer on 4/16/09.The temperature difference is shown.We have done similar tests in thepast, with similar results.

There does not appear to be any significant error in our temperaturemeasurements.

T# Read Refere Differ1 19.96 19.958 0.0022 19.97 19.966 0.0043 19.96 19.956 0.0044 19.94 19.943 -0.0035 19.93 19.931 -0.0016 19.88 19.875 0.005

Reference Undulator

16 Zachary Wolfwolf@slac.stanford.edu

16Undulator Tuning StatusJune 9, 2009

Kugler Bench Reference Dipole

(Bhall – Bnmr) / Bnmr

is stable to better than10-4 over the past year.

Reference Dipole,uniform field,

NMR measurements

Reference Undulator

17 Zachary Wolfwolf@slac.stanford.edu

17Undulator Tuning StatusJune 9, 2009

Hall Probe Calibration History

a) Bcalib – Bnom vs Vhall

Bnom is linear in V. (Take out linear part of calibration.) See some changes in probe.b) At V = 5 V (1 T), change in calibration over time. See an ageing of probe. Calibration takes this out.c) Residuals Bmeas – Bfit

Residuals less than 0.2 G.

a)

b)

c)

Reference Undulator

18 Zachary Wolfwolf@slac.stanford.edu

18Undulator Tuning StatusJune 9, 2009

SN16 Radiation Damage Test

Heinz-Dieter will comment on the dose and the number ofequivalent years of usage.

19 Zachary Wolfwolf@slac.stanford.edu

19Undulator Tuning StatusJune 9, 2009

SN20 Radiation Damage Test

Heinz-Dieter will comment on the dose.

20 Zachary Wolfwolf@slac.stanford.edu

20Undulator Tuning StatusJune 9, 2009

Undulator Repairs

Straightness Repairs Are Complete6 Undulators

Before After

21 Zachary Wolfwolf@slac.stanford.edu

21Undulator Tuning StatusJune 9, 2009

Undulator Repairs

SN6 needs the end poleassemblies re-installed.

SN4 needs a pole repaired.

We are setting up a labto do this work.

In addition, we will install ablock magnetizer and a

helmholtz coil in this lab torepair undulators and allow

prototype development.

22 Zachary Wolfwolf@slac.stanford.edu

22Undulator Tuning StatusJune 9, 2009

Conclusion28 undulators are in the tunnel33 undulators will be installed in JulyReference undulator trajectories and phases are stableReference undulator axis position indicates rms ∆K/K errors of 3×10-5 for production run 2MMF temperature measurements appear accurate by comparing to a reference thermometerReference dipole measurements are stable to 10-4 determined by comparing the hall probe to an NMR.Hall probe calibration fits have residuals less than 0.2 G.The hall probe shows some ageing with time. (The calibrations correct this.)A radiation damage test was done and no damage was detected.The final undulator repairs are in progress.Studies of K vs temperature will start as soon as the production work is done.We need to tune 6 spare undulators and then we are ready for routine radiation damage checks.We will be able to fix undulators and build small prototypes with our fixturing and block magnetizer.