1. Undulator Tuning Status
Z. Wolf, S. Anderson, R. Colon, S. Jansson, D. Jensen,
S. Kaplunenko, Y. Levashov, Ed. Reese, A. Weidemann

2. Undulator Tuning Status
Overview
Status/Schedule
Reference Undulator
Undulator Repairs
Radiation Damage

3. Re-Tuning We are re-tuning all the undulators because of
damage from temperature excursions
beam pipe interferences

4. Re-Tuning Schedule 25 undulators are in the tunnel
8 undulators are still required
2 undulators need repair
6 spares need to be tuned
K vs Temperature studies still
need to be done

5. Reference Undulator X-Trajectory, Y-Trajectory, Phase vs Z,
measured many times
X-Trajectory,
Y-Trajectory,
Phase vs Z,
Phase In Cell,
all stable

6. Field integrals stable,
Reference Undulator
I1XvsX
I1YvsX
Field Integral
Measurements,
Long Coil
Reference Undulator
never tuned for
±6 mm good
field region
I2XvsX
I2YvsX
Field integrals stable,
but some systematic
changes

7. Reference Undulator Started straightening coil routinely, improved
I1X vs Time
I1Y vs Time
Field integral
changes possibly
due to
coil straightness
Field integrals
at X=0
at different
times
I2X vs Time
I2Y vs Time
Started
straightening
coil routinely,
improved
repeatability

8. Reference Undulator 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.

9. Undulator Tooling Balls Relative To Beam Axis
Reference Undulator
Undulator Tooling Balls Relative To Beam Axis

10. Change In Beam X Position Relative To X Tooling Balls
Reference Undulator
Change In Beam X Position Relative To X Tooling Balls
Average change
doesn’t affect
performance.
RMS change is
important.

11. Change In Beam Y Position Relative To Y Tooling Balls
Reference Undulator
Change In Beam Y Position Relative To Y Tooling Balls

12. MMF Temperature History
Reference Undulator
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.

13. MMF Temperature Excursions T > 22 C
Reference Undulator
MMF Temperature Excursions T > 22 C
The large temperature
excursions are not
responsible for the
slope in the beam
axis x-position plot.
deg C

14. Hall Probe Calibrations
Reference Undulator
Hall Probe Calibrations
The hall probe was
calibrated several times
during the tuning. The
changes in x-position
remained. Hall probe
calibration errors do not
appear to be responsible
for the change in beam
axis x-position.

15. MMF Temperature Accuracy
Reference Undulator
MMF Temperature Accuracy
T# Read Refere Differ
Yurii compared our temperature
measurement system output to a
reference thermometer on 4/16/09.
The temperature difference is shown.
We have done similar tests in the
past, with similar results.
There does not appear to be any
significant error in our temperature
measurements.
deg C

16. Kugler Bench Reference Dipole
Reference Undulator
Kugler Bench Reference Dipole
Reference Dipole,
uniform field,
NMR measurements
(Bhall – Bnmr) / Bnmr
is stable to better than
10-4 over the past year.

17. Hall Probe Calibration History
Reference Undulator
Hall Probe Calibration History a) c)
Bcalib – Bnom vs Vhall
Bnom is linear in V. (Take
out linear part of calibration.)
See some changes in probe.
At V = 5 V (1 T), change in
calibration over time. See an
ageing of probe. Calibration
takes this out.
Residuals Bmeas – Bfit
Residuals less than 0.2 G. b)

18. SN16 Radiation Damage Test
Heinz-Dieter will comment on the dose and the number of
equivalent years of usage.

19. Straightness Repairs Are Complete
Undulator Repairs
Straightness Repairs Are Complete
6 Undulators
Before
After

20. Undulator Repairs SN6 needs the end pole assemblies re-installed.
SN4 needs a pole repaired.
We are setting up a lab
to do this work.
In addition, we will install a
block magnetizer and a
helmholtz coil in this lab to
repair undulators and allow
prototype development.

21. Conclusion 25 undulators are in the tunnel
33 undulators will be installed in June
Reference undulator trajectories and phases are stable
Reference undulator axis position indicates rms ∆K/K errors of 3×10-5 for production 2
MMF temperature measurements appear accurate by comparing to a reference thermometer
Reference 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.