IR Demo FEL Upgrade Project
June 2000 was the first month of the IR Demo FEL Upgrade project which began officially on June 1, 2000 with the sign-off of the Dept. of Navy/Dept. of Energy Memorandum of Agreement. A successful project kick-off meeting was held on June 12-13 with an outside review team chartered by ONR and DoE. Copies of the review team's report are available from the project contract monitor, John Albertine.
The project hosted the biannual Laser Processing Consortium Workshop on June 19-20. The workshop was attended by approximately 80 participants. The workshop agenda included discussion of the upgrade capabilities, the results from the March 2000 FEL user run and planning for the July 2000 FEL user run.
Project Cost Performance
The project budget for the period, June 1, 2000 to Sept. 30, 2001 is $9,029k. The project through the month of June 2000 has a total of $603k of performance scheduled (assuming the project started at the originally planned start date of April 1, 2000). The work performed through the end of June was $140k, which is 1% complete vs. 6% scheduled. The actual costs accrued through June totals $89k. This results in a schedule variance of -$463k and a cost variance of +$51k. We expect to carry the schedule variance for about the first half of the project until we recover from the 2-month delay in the start of the project.
Beam Physics: (WBS 3)
The documentation for Rev.1 of the upgrade accelerator driver lattice was completed and posted on the web at www.jlab.org/~douglas/FELupgrade/masterindex.html. We received a proposal from the Naval Postgraduate School for modelling efforts that support the upgrade.
Injector: (WBS 4)
We have started qualification bake-outs of the apertured cesiator which we have designed as an improvement to the current gun cesiator which evaporates cesium over too large an area of the cathode surface exacerbating the high voltage processing. The three spare ceramics for the gun assembly were shipped to LBL for ion implanatation. This process enables leakage charge to be drained from the ceramics without damaging arcs. Discussions have been initiated with the supplier of the gun high voltage power supply concerning the modifications necessary to handle the higher current needed for the upgrade (10 mA vs 5 mA).
SRF (WBS 5)
P. Kneisel returned from a visit to KEK/Japan where he investigated KEK's use of electropolishing for producing high gradient SRF cavities. As presented at the project kick-off meeting, we are considering the option of using electropolishing as an alternative to the present buffered chemical polish (BCP) depending on the results of a test with multi-cell cavities.
RF Systems: (WBS 6)
The order for the high power (100kW) klystrons for the upgrade injector was placed. This is the long lead procurement in this project. A design review by the klystron vendor is scheduled for August 29. We are making preparations for installing waveguide in the 3rd cryomodule position through the FEL ceiling penetrations during one of the weekend shut downs during the upcoming July user run.
Instrumentation and Controls: (WBS 8)
Parts for prototype 3" BPM are nearly complete. The drawings for the 3" shielded beam viewers are in detailing. Progress is being made on new optical diagnostics. These coupled with sample and holds will be used as permanent FEL power meters and will display energy-per-micropulse. Additionally, quadrant LiTa are being assembled for use as an optical beam position monitoring system. Status lamps have been added to each of the user labs to indicate state of the FEL – a simple indication of when the FEL beam was off.
Beam Transport: (WBS 10)
We have obtained two bids on the large order (80 tons) of type 1006 steel we will need to fabricate the upgrade dipoles. We continued layout of the GX prototype dipole, refining the details of the insulation system by consulting with vendors before freezing the configuration. 3-inch quadrupole yoke machining has started and the annealing specification was signed off. Coil prints are being back checked. Continued to create the 3-D magnetic model (TOSCA) of the 3-inch quadrupole. We have delayed making further samples of dipole chambers until the definition of the prototype dipoles is more advanced. We have started some preliminary lay-out for stands and have begun testing of the magnetic properties of the steel we will use for the dipole vacuum chambers
Wiggler (WBS 10)
Created the detailed drawing of the optical klystron on its strong back with all diagnostics, vacuum pipe, dispersion section and water manifolds so that existing parts could be modified and new parts made. The bus bars and mounting plates were received. The shop started making tooling in anticipation of making the coils. The insulated conductor was received from the insulation vendor. Finished the plug concepts for disassembly of electrical leads for power and safety circuits during installation.
Optics (WBS 11)
We have begun the preliminary lay-out of the R5 mechanical design. We have reviewed the analysis supplied to us by AES of the conceptual mirror cooling configuration that was jointly designed with AES and are ready to proceed with the next design step. We have brought new optical diagnostics on line to support operations. We have added a diagnostic for measurement of the FEL mode quality.
We completed hot check-out of the IR Demo in order to fully prepare the machine for user operations which began on Monday (June 26) and will continue until August 4. We achieved kilowatt operation at 3 microns in preparation for the first PLD (pulsed laser deposition) experiments on June 26th which have requested high power operation at this wavelength. For the upgraded injector we plan to eliminate the obstructions in present light box which prevent us from using larger areas of the photocathode. We also completed re-certification of the Laser Safety System (LSS) prior to operations. During the first full week of user operations data was taken on ablation rates, trepanning experiments were carried out, and the first scanning-near-field microscope images were acquired. The laser has lased well, with over 1% efficiency obtained on a routine basis with 6% duty cycle at 3.1 microns. Mirrors have been received for operation at 1 micron in July.
International FEL Conference, Duke University, Raleigh/Durham, NC, Aug. 14-18, 2000.
Linac Conference, Monterey, CA, Aug 21-25, 2000
3rd Annual Directed Energy Symposium, Albuquerque, NM, 31 Oct - 3 Nov, 2000.