IR FEL Monthly Report for January 1997

Navy IR Demo Contract WBS Elements

WBS 1 Project Management

January 1997 was the seventh full month for the IR Demo project funded by the Navy.

The project performance system since the project start in June 1996 utilized large value ($100k) pegpoints within the individual WBS elements to assess cost performance. This procedure was changed during this reporting period (January); all WBS elements are now reporting on the pegpoints as scheduled, regardless of their respective value. With the exception of the change in WBS 9.6 (Optics) noted below, no pegpoints were rebaselined or rescheduled in this change of reporting procedures. This new procedure has resulted in some significant changes in the summary level reports and several WBS elements: Instrumentation and Controls, RF, Cryogenics, and Optics. With regard to Optics, this WBS element underwent a major schedule revision to better align the work with the remaining schedule period and to provide a more definitive description of the work. This did require that most incomplete pegpoints be rescheduled; history was not changed.

The IR Demo project through the month of January 1997 has a total of $3,803k of cost performance scheduled (less the SRF and User facility tasks). The work performed through the current period is $3,189k which accounts for 39% of the project completed. The actual costs accrued through January totals $3,081k. This results in a schedule variance of -$614k (an increase of $58k) or six weeks slip in schedule, and a positive cost variance of $172k ( a decrease in the favorable variance of $217k). The User Facility Building is being reported as $69k behind schedule and $48k undercost. The project achieved BOD for the first floor during January, which is ahead of the scheduled milestone. The projected BOD in April for the second floor is approximately two weeks late.

As a follow-up to the Dec. 17-18th MTAC meeting, an internal planning meeting was held to strategize on various upgrade options for the IR Demo that would be most useful to the Navy and industrial missions and leverage potential accelerator technology to be developed by the APT program.

We held the winter workshop of the LPC on January 21-22 and approximately 65 attendees were present. Fifty participants were from outside the lab. Three of the working groups, polymer processing, metal processing and micromachining made good progress towards planning for initial utilization of FEL user laboratories. Plans for a fourth laboratory presently designated for use by personnel from the Navy and NASA are still in an early stage of discussion. No firm commitments are in place from NASA yet nor could be represented by NASA attendees at the workshop. Proposed experiments by the NRL staff are projected to require only a small amount of beamtime. There were preliminary discussions at the workshop on mechanisms for laser user interaction with the user facility, methods of allocating beamtime and draft user facility agreements.

The agenda and charge were finalized for the DOE-BES review to be held on Feb. 23-24. Commitments were obtained for the external reviewers.

In view of the slippage in the fabrication of the new HV for stack assembly, the photocathode gun, coupled with our commitment to install the IRFEL in the FEL Facility by 30 Sept. 97, we formulated a contingency plan that preserves both the schedule and technical content of the Program. The central idea is, if necessary, to delay complete debugging of the injector until after its reinstallation in the FEL Facility. This saves time because it avoids a duplicity of 10 MeV commissioning activities, i.e., in both the ITS and FEL Facility. The resulting schedule accommodates two important global concerns. It employs Jefferson Lab manpower when it is available for the reinstallation activity, namely during summer 1997. It also gives us a reasonable chance to meet the Dec. 97 first-light milestone.

The December monthly report for the IR Demo project was completed and distributed on Jan. 29. A laboratory-wide scheduling and resource planning effort was completed on Jan. 31 in order to resolve conflicts and optimize the use of the laboratory's design, fabrication and installation labor for support of the experimental halls and the IR Demo project over the next 12 months.

WBS 5.0 Instrumentation & Controls

Beam Instrumentation: The BPM review close-out is scheduled for Jan. 9. The stripline prototype BPM was successfully modified to eliminate the 1455MHz resonance, currently this contract is in procurement. The multislit emmitance monitor is operational (using a PARMELA output). The beam viewer mechanics are complete and being leak checked. Fabrication continues on beam viewer and stepper motor controls.

Personnel Safety System: Procurements and documentation continue. The rack positions were moved to zone 15 (telephone room), this is due to space conflict with the LCW piping. The new location is actually more convenient; it is located where the fiber optic connections enter the FEL building from the Main Control Center (MCC).

Machine Protection System (MPS): The MPS hardware procurements from Argonne took longer than anticipated; the purchase order did not get awarded in January. These components are "off-the-shelf" from APS so there they are not on the critical path.

Control System Hardware: The purchase requisition for the server computers did get signed and is proceeding. The overall layout and design continues.

Control System: Software The software for the machine protection system is being debugged on borrowed MPS boards from Argonne.

DC Power: The trim rack fabrication continues. Drawings with magnet nomenclature are being finalized, following this the cable databases will be setup.

Vacuum Controls: The ion pump power supplies are 70% complete. The ion pump power supply control card had a problem and was reworked. The vacuum control PCB's first articles were checked out well and the fabrication is proceeding.

WBS 6 Cryogenic Distribution

Quad transfer line installation is under way. Both shield return circuit inner and outer pipes are welded and the outer pipe is being leak tested. When this leak test is complete, the vacuum jacket can be finished and the milestone for installation should be taken in Feb. 97. Linac return transfer line modules #1,2,3,4 are complete and #5 will be done by February 12. We will start taking modules to the tunnel in February if the building floor is clean and there are no objections from the contractor. Welding will start after survey and alignment has completed putting reference marks in the building for us to align the transfer lines.

Fabrication of the sleeve supply and return transfer lines has started. Detail design of sleeve transfer lines is complete and the field flex can is progressing. Installation of the gas lines in the linac is nearly complete and will be finished in parallel with transfer line installation. All procurements for instrumentation and control are complete. Fabrication is 55% complete.

WBS 7 Beam Transport

The design of the Reverse Bend Dipoles and the 180-degree Dipoles continued at Northrop Grumman while the design of the Optical Chicane Dipoles entered the checking phase. Layout of the Injection and Extraction Dipoles started at a moderate pace.

The Design Review of the Recirculation Dipoles was closed out. Tests of the Prototype Dipole on the Magnet Test Stand yielded solutions to obtaining the field uniformity required over the large volume of the beam envelopes in all the dipoles. The magnet design can be characterized as :

-Window frame style with saddle coils using water cooled conductor

- Field clamps

- Mu metal pole tips with Purcell gaps between the main magnet iron

- Evenly distributed conductors in the coil bundles

- Extra width to provide the expected field integral over the entire horizontal aperture

The main punch list item from the December Vacuum Review was closed out as the method for handling vacuum around cryomodules was simplified from the extensive baked system originally anticipated. The final design has a minimally baked region near the cryomodule ends separated from the remaining unbaked system by differential pump stations. Most vacuum hardware entered the procurement process.

Design of stands, girders and vacuum pipe received a boost as the generic stand and girder for the quadrupoles in the back leg was nearly completed. At the same time, the vacuum chamber for the injection/recirculation intersection was perfected and signed off. Both these items act as precursors for all the remaining stands, girders and chambers.

The design of the system of dumps, including injection dump, extraction dump, straight-ahead dump and the insertable dumps as well as the collimator underwent extensive analysis in anticipation of a review in early February.

The two low conductivity cooling water systems, one for magnets that connects directly with the south Linac and the other a closed loop for dumps were defined during the month.

WBS 8 RF Systems

The waveguides and HOM filters are all assembled on the quarter cryounit and waiting for the installation of the warm windows. The Chopper coupler, cables, and water skid were installed again after the beam line was baked. The new cooling fins for the Chopper's drive probe were attached and connected to the water line. The new downloadable code and screens for the Buncher/Chopper code were finished and are ready for testing. The new code for the quarter cryounit will be tested this month. The network server, itssrv, was installed last week. The RF files were moved and are working fine. The software for the mechanical tuners is to be installed for the quarter cryounit. The waveguide penetrations in the cave roof were plugged with sand last week. Rad Con has approved and will inspect when we start beam operations. Spare 50 kW klystron was received last week and is being prepared for acceptance tests. The tests are scheduled to start next week. The beam line and gun were baked and reassembled in preparation for the 350 MeV experiment. Hipotronics expects to deliver in May 1997 the first unit of the 225 kW variable DC power supply. The third 60 kW Klystron has arrived from Russia. We will begin testing it during February. This tube was tested and operated at up to 85 kW at the factory! We will attempt to duplicate the test results. RF leakage hazard, area monitors on order, expect delivery in February. The personnel safety system interlocks were connected to the 50 kW systems and commissioned.

WBS 9.2 Injector Move

The design for the high voltage power supply was completed and sent to vendors. Due to unavailability of hemispherical heads, the design had to be modified to incorporate elliptical heads. At month's end we are awaiting final bids for the tank. To make sure that the design was sound, a finite element analysis was carried out by Northrop Grumman so that the tank design had a healthy safety margin.

The laser clean room for the new facility was sent out for bids. The bid deadline had to be extended due to lack of competitive bids. We expect the bids to come in early February.

Work continued on injector layout design. About 30% of the design work is complete. We are on schedule to have all new components in place by June 1.

WBS 9.4 Wiggler

The design of the wiggler supports was completed and all parts were procured. Northrop Grumman has made good progress on the vacuum chamber and vacuum chamber support design. The vacuum chamber is at the 90% level and the support is at the 30% level.

STI Optronics has completed all the mechanical components for the wiggler. They have received most of the magnets from Shin-Etsu and they are measuring them. Final measurements of the wiggler will be done by March 21.

The radiation safety group at Jefferson Lab has done an analysis of the effectiveness of shielding upstream of the wiggler in limiting the dose received by the NdFeB magnets in the wiggler. These magnets can be damaged by doses in the 100 MRad range. This analysis will also allow us to gauge the dose using integrating dosimeters near the wiggler.

WBS 9.6 Optics

With the optical cavity assemblies in fabrication, January activities concentrated on completing the designs for the optical transport and diagnostics. The elements that received attention were the turning mirrors ("mirror cans") and a diagnostic pickoff. By month's end, both were being reviewed for changes. As mentioned earlier, the collimator must be redesigned, and conceptual layouts were prepared for internal review. The gimbal mounts, received on 31 Dec., were turned over to our designer for dimensional checks. He found discrepancies, mainly in the size of the gearboxes that required revisions to some of the drawings. These were made, signed, and given to the Machine Shop. This created a delay in some parts by about two weeks, which should not cause any problems. Procured parts continued to come in, major acquisitions were the IR detectors (indium antimonide and mercury cadmium telluride). The sensitivities of two cameras that will be used for synchrotron light monitors, a cooled CCD, and an intensified CCD, were determined at 633 nm. There was also some progress in the software development for the optical cavity controls. The LabView program for controlling the monochromator/spectrograph is being modified to make the controls more intuitive, and to add scanning. The electronics for the Mach-Zehnder interferometer were simplified and are undergoing some final checks before hardwiring.

ITS

Test runs of the photocathode drive laser showed it to be quite stable, even after the lamps were changed. It appears to be operating as it did when it was new. The divide-by-two electro-optic modulator, with it's new lithium tantalate crystals was installed and developed photorefractive damage during testing. It was returned to the manufacturer, who is going to try c-axis lithium niobate. This created a longer cell, and we had some new mounts fabricated in order to translate several optical components.

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

Injector Test Stand (ITS)

The month of January was dedicated to completing the installation activities in the ITS, including the experimental setup for simultaneous transverse/longitudinal phase-space diagnostics of the electron beam from the photocathode gun, and preparing the gun for renewed operation at 250-300 keV. Activities leading to reconfiguration of the gun for higher-voltage operation also proceeded in earnest, with the goal of upgrading the gun at the earliest opportunity. By month's end, plans were to operate the gun for about two weeks beginning early February, during which the experimental setup would be fully commissioned and more information would be obtained about operational lifetimes. Subsequently, the gun would be reconfigured for 350 keV operation, with operation at that higher voltage occurring for about three weeks in March.

Ion implantation of a dummy cylindrical ceramic at Lawrence Berkeley Lab was very successful, yielding a resistance right in the middle of our target range. Unlike the Cr/V-oxide-coating process, the ion-implantation process offers far better control of, and provides a real-time in-situ measurement of, the resistance. Consequently, we decided to stop pursuing the Cr/V-oxide- coating process. We also continued the effort to coat the cathode-support tube with a field- emission-resistant coating. By month's end, FM Technologies was projecting completion by mid- February. Thus, by mid-February, we expect to have several options available for refurbishing the gun.

Other developments in the ITS included refurbishing the drive laser for improved reliability and more stable operation. We also received the third Svetlana klystron which will serve as a spare for the FEL injector. High-power-rf testing of the cryounit awaits installation of suitable ceramic warm windows. By month's end, we still had not produced warm windows that survive their acceptance tests, but the effort to do so is continuing with vigor.

WBS 3 Cryomodule

Cavity pair parts:

Cavity pair components have been fabricated to support the start of pair assemblies. Pair parts production continues and should not have a problem staying ahead of cavity assembly schedule.

Cavity testing:

Five cell cavity test performed to qualify cavity and HOM Load performance. Test results are positive, cavity and HOM loads are good.

Cryounit assembly:

Cryounit assembly scheduled to start in February. Tuner components and shields are expected in February. Delivery schedules should not be a problem for assembly schedule.

Cryomodule assembly:

Bridging rings are schedule for delivery in February. This is the last major component left to receive. Qualification of components is ongoing. Scheduled assembly start is in March. Anticipate no problems with start of cryomodule assembly.

Schedule overview:

Right now we are approximately one month late on our assembly schedule and on our procurement schedule. Assembly schedule should be made up by the end of March.

WBS 2 Beam Physics

The bulk of the beam-physics activities during January were centered on supporting the deliberations of the Dipole Magnet Review. In particular, a considerable amount of linear- tracking studies was done to finalize specifications for the dipoles, an activity that was guided by strong coordination with magnet engineers and results of testing the prototype dipole magnet. The development of the lattice and magnet specifications is being documented and will soon be posted to WWW.

Theoretical studies of coherent synchrotron radiation (CSR) continued. One accomplishment was to resolve conclusively the influence of coulomb forces arising from a straight-line trajectory leading into a bend magnet. These forces, in combination with localized CSR forces, make an important qualitative contribution to the transient self-interaction of an electron bunch. Although our past estimates for emittance growth in the optical chicane (of order 10%) and 180-degree bend (of order 50%) did not include these forces, they still hold as rough approximations. However, they could conceivably be modified substantially once we come to the point of having detailed self-consistent numerical simulations. We have taken initial steps toward developing simulation tools, and this activity is one that will occupy us over the next few months, ultimately in support of CSR experiments planned for the IRFEL's beam-transport system. Suffice it to say that the CSR problem is most intricate!

WBS 4 Commissioning/Operations

A complete list of electron-beam pulse formats, spanning all phases of commissioning and operations of the IRFEL, was compiled and posted on WWW.

Given the decision to operate the existing gun and commission the new experimental beamline, preliminary plans were made toward organizing the purpose of, and staffing for, the upcoming runs. This included writing detailed plans for the experiments. In addition, as part of planning for commissioning the IRFEL, we developed the contingency plan for the FEL injector mentioned above under "Injector Test Stand".

Operations/commissioning activities also were focused on supporting the closeout of the Dipole Magnet Review, including resolving questions related to operational requirements for the dipole magnets. For example, the method for phasing the beam at 42 MeV using the injection/ extraction dipoles was finalized, which in turn has led to firm guidelines for the designs of these magnets.

Candidates for charge-coupled-device (CCD) cameras were identified for use in conjunction with synchrotron-light monitors. One outstanding question is their robustness in a radiation environment. Testing is underway; on 31 Jan 97 a camera and dosimetry were installed in the nuclear-physics injector to get an indication of camera lifetime during operations in February.

Options were considered for scheduling the commissioning of the energy-recovery loop vis-a-vis obtaining first light. At this time, we are planning to commission the hardware along the recirculation loop in parallel to achieving first light, and afterward, to commission fully the process of energy recovery.

Facility

Significant steps forward occurred this month in the facility. Early in the month the piping for the low conductivity cooling water was finished and pressure tested. The elevator shaft was encased in concrete blocks. The utility room slab was laid out and then poured as was the loading dock and pad for the main power transformer and the HVAC compressor. The main power transformer was placed in position. Four feet of sand fill was put in and compacted in the interfloor area. Various utilities were buried in the fill, rebar laid out and the second level floor poured. After curing, the concrete workers began loading the steel framing onto the second level. By the end of the month steel framing was partially placed over the first and second floor entrance area and work was beginning to proceed to the west. The subcontractor for the framing miscalculated several pieces in the east end and rework was required to get sections that would fit and interconnect in the stairwell area roofline. Approximately a week delay has resulted from this and related problems at the frame house. Power distribution boxes were placed on the second level. Downstairs, Jefferson Lab surveyors established a coordinate grid and measured the as-built positions of waveguide feedthroughs, columns, etc. Floor elevations were mapped. Piping was hung on the walls for the LCW, dry nitrogen, etc., feeds. Lighting fixtures were installed in the lower level and wired up. At the present time a two week delay in contractual BOD to the second level area is expected with initial access occurring around April 1. Primary causes of this delay are mis-calculations by the framing contractor and delays in getting the interfloor area filled with sand because of holiday shutdowns at local sand pits. Flooding in the lower level during heavy rains has been a problem with the accessways not yet fully enclosed. Work is underway to seal the lower level against water so that equipment installation can begin starting with the cryogenic lines.

Upcoming Meetings and Reviews

SPIE High Power Light Source Conference Feb. 8-14, 1997

DOE Basic Energy Science Review Feb. 24-25, 1997