Navy IR Demo Contract WBS Elements

WBS 1 Project Management

September 1996 was the third full month of activities for the IR Demo project funded by the Navy. A total of $1,438k of costs have been obligated. With respect to the planned accrual of project cost by September ($1,231k), $954k of work was accrued which accounts for 12% of the project completed. The actual costs accrued through September totals $1012k. This results in a negative schedule variance of $277k and a positive cost variance of $58k. The $3.5M FEL Facility is running over one month ahead of the established performance schedule; $950k of actual costs have been accrued on the building and this task is 33% complete.

The first installation planning meeting was held on Sept. 20 with WBS managers and representatives from the installation teams to begin coordination of the installation tasks in the FEL building. Detailed lists of tasks and labor estimates are being reviewed with the goal of optimizing the use of labor and minimizing the conflicts with the support of the CEBAF accelerator operations.

A successful review of the optical cavity design for the IRFEL Demo was held on Sept. 26.

A Workshop for the Laser Processing Consortium was held on Sept. 9-10th with approximately 64 attendees from most of the institutions presently in the Consortium and observers from several organizations interested in LPC activities. The metal processing working group and micromachining working group were well represented at the workshop. Technical issues related to User Lab operations, equipment lay-out, safety and equipment interface were discussed. Action items for all the working groups and Jefferson Lab were identified. A summary of the workshop and working group sessions is in preparation.

On Sept. 24-26 we hosted a workshop on scaling FELs to the megawatt-power class for Northrop Grumman and the Navy High Energy Laser Office. Approximately 50 people attended the workshop which included representation from all the major laboratories in the US with FEL activities. Two classes of baseline machine concepts were examined: (1) a regenerative amplifier and (2) an oscillator with energy recovery. A list of high-level technical issues were identified for working groups to examine the necessary technology extrapolations and technical risks from existing demonstrations to high-power devices of interest to the Navy. Workshop summaries will be distributed to all attendees.

WBS 5.0 Instrumentation & Controls

The contract with University of Georgia for two bunch length monitoring systems has been awarded. The first unit will be delivered for testing in the injector test stand. The 2 inch round Beam Position Monitor mechanical design is in prototyping. The design for the 5 wide chamber devices has begun. The 1 1/2 inch diameter shielded beam viewer parts are complete and are being assembled. The 2 inch shielded beam viewer parts are being procured.

The hazard assessment for the Personnel Safety System is proceeding as well as procurements for this system.

The software required for the IRFEL is being written for use in the Injector Test Stand (ITS). The emmitance measurement software has been tested with beam and is operational. The beam viewer software is functional and much progress has been made with the video imaging hardware and software which will output a position from the spot on the beam viewer.

Drive laser remote instrumentation and control has been specified. The design for the interlocks, monitoring instrumentation and control is progressing. A hardware interlock has been built to protect the laser against variations in RF power from the control modules.

The vacuum systems controls are also progressing. The procurements for the ion pump power supplies are nearly complete.

WBS 6 -- Cryogenic Distribution

The Quad transfer line (TL) fabrication is complete. We now have about 240 feet of line ready to install. When the FEL/CHL bayonet can (see below) is complete we may start this installation, depending on manpower, weather and schedule.

Fabrication of the FEL/CHL TL bayonet can is projected to be complete by Oct. 15.

Detailed design of two supply sections of the FEL building supply transfer line are complete and approved for fabrication. A third design is 99% complete and will be released by Oct. 3 for fabrication. Detail design of one section of FEL building return transfer line has been released for fabrication (currently 50% complete). Bayonets and valves for building supply and return transfer lines are being fabricated.

Detailed design of the CHL header extensions was completed and fabrication has started.

Detailed design of the CHL U-tubes is 40% complete.

The piers for the quad transfer line are complete.

WBS 7 -- Beam Transport

Significantly more manpower will be available at month's end as one more engineer and two more designers join the effort from the Engineering Group.

The impedance analysis of the vacuum system by B. Yunn revealed that only half to two thirds of allowed impedance budgeted for the machine was spent, indicating no problems with our relatively conventional vacuum pipe construction.

Testing of the prototype dipole magnet indicated that both the original design and the design with added field clamps didn't suppress fringe fields to within reasonable levels or yield the value for K (edge focusing parameter) that the lattice was designed with. A design of a prototype saddle coil configuration as a field clamp to reduce fringe fields and lower the K value was completed. The dipole magnets are about one month behind schedule and this issue adds six weeks to the slip because all the designs to date have to be modified to a saddle coil configuration. We plan to go for a separate procurement for the optical chicane dipoles to gain time and to decrease the liberal fabrication time in the original schedule to meet the September 97 milestone for hardware installation.

A high mu material for the injection chicane dipoles was identified and ordered for use on the prototype dipole after the above saddle coil measurements. This activity is also behind schedule and reaching critical path.

The package of specs and drawings for the weak quadrupole is being prepared for procurement. The liberal fabrication time will be reduced to a tighter schedule, possible because only 18 magnets will be fabricated out of the required 28. The others are available as surplus from the CEBAF machine, which helps ameliorate the WBS 7 budget issue noted below.

Work slowed on defining procurement packages for the vacuum system components. We plan to make up this slip with the use of the newly available engineer above.

Fabrication of the prototype the trim quadruple started as did preliminary design of the Sextupoles.

Reducing the cost from the increases in scope still remains an05 issue as detailed design continues to drive toward complexity and increased cost.

WBS 8 -- RF Systems

The high gradient Buncher was conditioned in the test cave in pulse mode to about 4 kW without any problems. It was run up to about 1.5 kW CW, but the rate of conditioning is limited by vacuum pumping capacity. It is expected to take a few more hours of conditioning to reach the design level of 2.5 kW. The water temperature control system has been running, but there is still some cleanup required on the controls and the main PID loop needs to be tuned.

Work is continuing on the cryomodule control racks and the 8 klystron HPA for the IRFEL. The specification for the 225 kW variable DC power supply is out for proposals. The procurements for the last major waveguide components have been awarded.

The standard CEBAF klystrons and circulators have been successfully tested at 8 kW forward power to a load and 8 kW reflected back into the circulator.

The high power waveguides for the quarter cryomodule are completed into the test cave. The 50 kW waveguide switch is installed for the SRF cryomodule test stand.

The production arc detector units have been built and tested. The first unit was installed this month and is operational for a 50 kW klystron and circulator.

New drive probes for the chopper cavity are designed and will be tested again in early October.

The detailed design, implementation, and documentation efforts were started this month to remotely control the buncher and quarter units with EPICS software.

WBS 9.2 Injector Move

The high voltage power supply is in the engineering design stage. Options are still being looked at for either moving or replacing the laser clean room for the injector.

Concerning plans for injector reinstallation: We held first two installation planning meetings and identified a set of related action items. These include identifying cables needed, reviewing the cable tray layout, and identifying the options for moving or replacing the laser clean room.

WBS 9.4 Wiggler

A mechanical design review was held at STI Optronics on September 13. Some errors in the drawings were found and corrected. The design is in compliance with the specifications and should allow for a simple interface with the vacuum chamber and supports. Final versions of the detailed drawings are expected in early October. The top level assembly drawing has already been received.

Using the top level assembly, work has begun on developing the conceptual design for the vacuum chamber and the support.

WBS 9.6 -- Optics

A review of the optical cavity engineering design was held on Sept. 26. The drawing package for the optical mounts were reviewed. Modeling results were also presented for the thermal distortion of the mirror substrates using CaF, sapphire, and silicon substrates.

Following approval of the resonator hardware at the Optics Review on Sept. 26, procurement of components was initiated with the purchase of optics blanks and vacuum components. A few minor drawing changes were initiated based on suggestions by the engineering review team which examined the drawings in parallel with the scientific staff review. Drawing signoff is expected shortly to allow release of components for fabrication. That will allow the component performance tests planned to proceed on schedule later this fall and early winter.

Injector, SRF, Facility, and Other Activities Outside Navy IR Demo Contract

Injector Test Stand (ITS)

The dc photocathode gun underwent commissioning and debugging in preparation for production runs to measure transverse emittance at 250 kV stand-off voltage. After installation of a new photocathode, the gun was operated at intervals from minutes to hours, at average currents in the milliamp range and charge per bunch in the tens of picocoulombs, without recesiation and without degradation in quantum efficiency. A number of refinements and improvements of both hardware and software were instituted to facilitate routine operation; these are enumerated in the weekly reports. At month's end, we could not yet operate routinely, but we were close to that capability, foreseeing production runs by mid-October.

There was major progress on the ITS 10-MeV hardware. The buncher cavity and its water skid were installed in the test cave, and its Temporary Operational Safety Procedure was signed off. Fabrication of the injector cryounit was completed, and the cryounit was installed in the SRF Test Cave on Oct. 1, where it will undergo acceptance tests.

WBS 3 -- Cryomodule

We completed fabrication of the cryounit for the Injector Test Stand. Acceptance testing of the cryounit is scheduled to be completed on Oct. 28. Once these tests are completed, we will then be able to finalize the design of the linac cryomodule.

Related progress includes: completion of the redesign of the shield circuit for the higher-order-mode thermal path, sending out requests for quote for fabrication of the magnetorestrictive tuners, and testing of the prototype split-flange conflat for the end-can beam tube. We also received bids for the bridging packages that will connect the four cryounits to form the cryomodule. All bids were high, so we will pursue an internal procurement path.

WBS 2 -- Beam Physics

Fine-tuning the design of the transport lattice continued. Addition of two simple dipoles on either side of the extraction dipole were shown to aid in phasing the rf cavities at 42 MeV. With this scheme, the field of the extraction dipole is lower, making it easier to build. The number of power supplies to power the transport-lattice dipole magnets has been increased from one to two to aid in achieving first light without having to do energy recovery. One power supply will drive the chicane dipoles, and the other will drive the recirculation dipoles. Both supplies exist from the inventory of the nuclear-physics machine. The transport lattices leading to the low-energy (10 MeV) dumps were frozen.

An analysis to ascertain the need for electron-beam scrapers was undertaken. A scraper placed in the first high-dispersion region of the first recirculation bend will add insurance for low (100-nA-level) beam loss during energy recovery. It will also suppress beam loss in the presence of unusually high energy spread, as might be generated in experiments involving high-efficiency extraction from the wiggler. Moreover, it can be used in experiments to study the interplay between beam loss and rf stability.

The data-reduction algorithm for the multislit aperture (for transverse emittance measurements of the 10 MeV electron beam) was essentially completed.

Other tasks include ongoing impedance analyses of diagnostics and vacuum-chamber components, as well as explorations in the details of coherent synchrotron radiation in preparation for future simulations that include it.

WBS 4 -- Commissioning/Operations

The structure of the Accelerator Readiness Review (ARR) Plan for the IRFEL was drafted. The IRFEL ARR process is envisioned to be simpler than that for Jefferson Lab's nuclear-physics machine. It can encompass incremental schedules and needs only one review coinciding with start of operations in Sept. 97. The plan still must be approved by the DOE site office, and it is estimated to take about 4 months to implement.

Considerable progress was made on the "10 MeV set-up procedure" for the FEL injector and its dump line. The dump-line design is now fully configured with the necessary magnetic optics and diagnostics to permit operating the injector as a stand-alone device after moving it from the ITS to the FEL Facility, an important check on the way toward achieving first light.

A list of all the current FEL beam diagnostics has been compiled and posted on the WWW. This list constitutes the baseline for the diagnostic suite and determines the associated development plan.

Facility

Non-conformances relative to the placement of four support columns were resolved. Excavation activities for the building are nearly completed.

Concrete was poured in the injector pit area (the final third of the lower level). We provided the contractor with signed drawings indicating all penetrations for FEL related utilities and hardware.

The forms for the ceiling pour in the west two thirds of the building were established. In addition walls were extended in the second third of the lower level, and the pour for the lowest-level floor was completed. Wall forms were placed in much of the east end. The overall building schedule is on track despite a very wet summer, and no significant problems are currently noted in the design or parts constructed.

Upcoming Meetings and Reviews

LPC Meeting (at AVS Symposium, Philadelphia) Oct. 15, 1996

SURA/Jefferson Lab Management Review Oct. 28-29, 1996

Internal Review of Vacuum-System Design Oct. 31, 1996

Internal Review of Magnet Design Nov. 15, 1996

Internal Review of Beam-Position Monitors Nov. 15, 1996

Maritime Technical Advisory Committee Meeting Dec. 17-19, 1996