1. LCLS Undulator System Detailed Report
Facility Advisory Committee Meeting
12 October 2006

2. Focus of this Talk Will Not Will Focus on the successes
We have had many and all major ones either have already been reported briefly at the plenary session or will be reported by the various speakers
Will
Focus on where the committee might be of help
I am focused now on making certain we deliver all components on time, within budget and to specification
Discussion of topics not yet presented to the committee or not being presented by others

3. Focus On Controls Vacuum Chamber Quadrupoles Major Contracts
Interface Definitions
Transfer of Information
Vacuum Chamber
Project management point of view
Parallel Efforts
Physics Viewpoint
Quadrupoles
Hysteresis Effects
Delivery Schedule
Major Contracts
Creation
Management
Beam Loss Monitor
Status

4. Controls SLAC now fully in the lead but
Recent estimate to completion exercise and rework of the P3 schedule leaves many opportunities for dropped balls.
Need to set up a detailed compilation of all controls items and responsibilities. This needs to be handed to SLAC controls so that they understand what it is that is required of them.
Need to sit down with SLAC controls and go through in detail what is in the schedule.
Hamid is Very Busy
Suggest creating a SLAC/ANL Controls liaison person much like we have for all the mechanical items. This person would work directly with the ANL LCLS controls technical lead to ensure than the controls interfaces and exchange of information proceeds seamlessly.

5. Project Management Point of View
Vacuum Chamber
Project Management Point of View
The prototype delivery date continues to slip. At this point if the prototype has a real problem then we have little or no time to correct for it.
Right now the vacuum chamber is roughly 20 days off from driving the assembly, but it is significantly further away from driving the project critical path.

6. Vacuum Chamber Parallel Efforts SLAC is pursuing a plan C.
ANL will not participate in this effort as we need to remain entirely focused with the resources that we have on completing the chamber as planned.
ANL is looking into a plan C’
In a recent discussion with Murray Gibson we decided that ANL could look into a plan to use an extrusion.
This might not take as long as one might guess.
We will not allow it to distract any resources from existing work either on the vacuum system or any other LCLS system

7. Vacuum Chamber Physics Viewpoint Difficult requirements Effect on beam
Some even difficult to define clearly
Effect on beam
May be difficult of impossible to ever determine
Non-unity Permeability of SS
Will impact field but more or less uniformly
As long as the random variation of K/K between undulators is kept below 1.5e-4 then the requirement is met
A slight increase in the overall field should not matter.
Choice of Steel (low permeability under all conditions)
316LN difficult to obtain locally. Some availability in Europe.
20Cb-3 Available locally and with short lead time.

8. Capenter Steel 20Cb-3 Specifications
Found Online
We Find
Electrical Properties
Electrical Resistivity ohm-cm
Magnetic Permeability
Magnetic Permeability 1.01

9. Quadrupoles Hysteresis Effect
Corrector coils act in “common” while quadrupole coils act differentially across poles
Places poles on different hysteresis paths
Need to use soft magnetic steel
Low remenance and low coecivity
Working with vendor and asking for expert advice on this

10. ‘QG’ Gun-to-Linac Quadrupole Magnets
-6 Amps
+6 Amps
-6 Amps
+6 Amps
From P. Emma
r  20 mm
Leff  7.6 cm

11. Quadrupoles Delivery Schedule Quadrupoles are near the critical path
They are certainly what holds up the assembly
Working directly with the vendor to refine their production schedule
Examples
Buy all materials up front. Don’t wait until after the 1st article has been accepted.
Use methods of construction that the vendor has experience with.

12. Major Contracts Still to be placed To be placed by Managing
Some vacuum system processes
Vacuum Support Structure
Support Mover system
Expect the vendor to deliver simple “kits”
RF BPMs
Bodies and receivers
Beam Finder Wire
To be placed by
Most by the beginning of the year
Vacuum by February
Managing
Will tap into the experience gain from the management of the undulators to manage all further contract to completion

13. Beam Loss Monitor Schedule Multitier Approach
Late start up, but still significantly off the critical path
No items in vacuum or in need of precision alignment during assembly
Multitier Approach
Follow DESY Example
Don’t reinvent the wheel

14. Beam Loss Monitor Multiple Detectors
Scintillators/Cerenkov Detectors coupled to PMTs
For low loss conditions
Needs calibration
Can achieve a broad detection dynamic range if allowed to vary the HV
Cerenkov Detectors
Thin optical fibers arranged around the vacuum chamber
Not sensitive to extremely low losses
Not simple to calibrate absolutely
Fiber optic
Long FO which browns as a function of dose at a known rate
Used for long term dose measurements

15. Short Break: BLM (Hi Sensitivity) Location
12/28/2018
Short Break: BLM (Hi Sensitivity) Location
BFW Ø10mm x 25mm long
BFW Ø18mm x 19mm long
Bellows Ø10mm x 76mm long
BLM 5mm x 12.5mm x 25mm long
RFBPM Ø10mm x 75mm long
Beam Guide Vacuum Chamber 5mm x 12.5mm x 3467mm long
Quad Spool Ø8mm x 158mm long
Test

16. Summary
We have accomplish a lot over the last 6 months
But there is still a lot to finish
We are interested in hearing your feedback to help us get over the last remaining hurtles so that we can deliver our equipment to SLAC and…