1. Undulator System Review Closeout Erik Johnson, Kem Robinson, Dieter Walz 4 March 2004

2. Specific Charge Aspects The scope of this review encompasses the entire undulator system, and includes the undulator magnet proper, the vacuum system, the diagnostics, the controls, and management/cost/schedule related issues. As such, the basic charge to the committee is: To review the LCLS undulator system and to provide advice on the overall system and the various subsystem designs and their suitability to meet the performance specifications, on the installation and commissioning plan, and on the overall project management of the LCLS undulator system.

3. Specific Charge Questions Review and evaluate the complete system design. Is the maturity of the design known to the level of detail to justify setting the cost and schedule performance baseline at this time? Response: Not at this time. Many of the subsystems are well prepared to be baselined, but the integrated system has many holes and gaps where uncertainties are quite large and approaches are not even at a concept design level. Identify any open design issues that should be addressed prior to setting the baseline. Response: The integration of rfBPM, quadrupole, vacuum chamber, the cradle (and its design) are of concern. Additional thought and direction on logistics, installation and handling are necessary as well (see specific section comments).

4. Specific Charge Questions (cont. [1]) Is the management team adequately structured for completing the LCLS design? Response: Yes, with one possible absence. Clear responsibility for total system integration, interfaces and engineering was not identified. A strong project engineering/manager would be very useful. Are there adequate resources and of the correct skill type to meet the needs of the project? Response: The present team shows very strong technical and project management strength. However, the dramatic increases in effort required in FY05 are a cause for concern. Augmenting resources so quickly inevitably resulted in a transitional period of decreased productivity and a slowing of progress. It is not clear that this has been adequately anticipated.

5. Specific Charge Questions (cont. [2]) Is the project progressing adequately? Response: Yes, with the resources and funding that are available considerable progress has been made. Progress since the November review is particularly noteworthy.

6. Specific Charge Aspect “Note that this is a pre-baseline (conceptual) design review.” From the DOE Manual 413.3 Concerning CD-2 Approval of the Performance Baseline marks the beginning of performance tracking. It also authorizes submission of the total project budget request. Key activities that take place leading up to the approval include preliminary design; development of key performance, scope and schedule parameters; risk assessment; establishment of a performance measurement system; identification of project interfaces; and development of the Project Execution Plan. From the DOE Manual 413.3 Concerning Preliminary Design. Preliminary design initiates the process of converting concepts to a design appropriate for procurement or construction. This stage of the design is complete when it provides sufficient information to support development of the Performance Baseline. The appropriate completion percentage is dependent upon the project. … For complex projects, the percentage of design may not be definitive because these projects may have many subsystems undergoing concurrent designs that may be at various stages of completion. Scientific systems, such as accelerators and detectors, production and manufacturing facilities, spacecraft and other systems, do not follow a linear process in which all subsystems reach the same maturity at the same time. Concurrency in these types of projects increases the risk because each subsystem design is dependent upon the design maturity of other subsystems.

7. General Comments The simple question to ask? Based on your present knowledge would you be willing to commit to build this for a fixed price at this time? Even though the undulator magnet is the critical path, there are many very near critical path items that are at a design stage which elevates concern. It is quite possible that very soon the critical path will no longer be through the undulator magnet procurements. A Risk Registry and Issues Log should be developed and implemented for the entire undulator system. When producing a cost/budget estimate provide a technology maturity and risk (technical, cost, schedule) assessment at the same time as providing a contingent-free (50%) number.

8. Undulator Magnet Systems Pleased to see assignment of a cost account manager to magnet systems that is also responsible for areas less mature in design development Developments since last review commendable Use of canted jaw K eff adjustment Removal of additional mechanical systems Schedule and procurement approach NdFeB vs Sm 2 Co 17 Delay in addressing previous recommendations has now precluded action in this area Experimental data does not strongly support conclusion Operational risks identified in November 2003 review still remain and have not been addressed Committee is not ready to endorse NdFeB material choice Two-vendor approach deemed essential

9. Undulator Magnet Systems (cont.) Procure the strongbacks, magnets, poles and granite (from same quarry face) from single source for delivery to undulator magnet assemblers Quadrupoles should have a dithering capability Cradle requires concentrated effort prior to baseline Requirements for cradle and undulator retraction not established Manual retraction of undulator magnet valuable for commissioning Undulator magnet has relatively low risk at this time On cradle: align BPM / quad to undulator magnet not reverse Concentrate on resolving design or prototyping complete system even at the expense of delay in delivery of undulator magnet first article

10. Magnetic Measurements Demonstrated measurements very good Approaches sound and well thought out Measurement capabilities well understood Fiducialization method looks good Magnetic needles the right approach Coordinate measuring system approach should allow integration of undulator system Techniques well established and evolved Effort to fully reduce to production may need to be revisited. Logistics and workflow in SLAC MMF need to be carefully studied Moving an undulator longitudinally is relatively easy Moving an undulator transversely or rotationally is is more risky

11. Interfaces/Support/Env. Concerns Environment evaluation provides important guidance Emphasizes need for beam based alignment BPM’s and adjustable quads Granite prototype could be deferred Trade information available should be evaluated Look carefully at support of granite benches Size requirements should be examined Access/ Installation to be factored into design Air flow concern for thermal gradients Integrated system performance should be modeled

12. Vacuum System Trade study for chamber design very good Follow up with prototypes Fabricability and finish Vacuum performance (voids/leaks) Mechanical performance (alignment stability) Transition pieces need evaluation wrt beam physics Shape changes Bellows motions Electrical conductivity/continuity through transitions Projected system performance during commissioning Pumping, gas loading, recovery time

13. Diagnostics Requirements placed on diagnostics by beam based alignment are well described Deferring intra-undulator x-ray diagnostics seems to be a sound decision Electron BPM near critical path Prototype development should be given very high priority Work on Optical Diagnostics at early stages Needs to proceed to more detailed design Should integrate consideration of required chamber transitions into the FEL physics Prototype system would be valuable for proving out system integration approach

14. Controls Good Overall Approach Undulator as stand alone control system Capitalize on existing platforms/software Task envelope well described Good knowledge base for detailed development Potential Concerns Integration with SLAC controls needs early attention Rapid jump in staffing in FY05

15. Concluding Comments “Keep on swimming”