We held our 13th Laser Processing Consortium/FEL Users Workshop on Jan. 17-18th. By all accounts it was a useful and informative meeting with 121 registrants. The full program for the workshop is given on http://www.jlab.org/FEL/LPC/lpcagenda02jan.html. The usual informal proceedings will be made available to the registrants and other interested parties when we have collected all the presentations.
This month we made significant progress with the installation of new hardware in the high voltage power supply for the Upgrade injector RF power supply. All three 100 kW klystrons were successfully tested to 50 % power levels (the limits of our presently installed power).
We received the first 20 of the Upgrade quadrupole magnets and submitted them to the magnet testing team. We have started the procurement process on the remaining ARC dipoles for the Upgrade with completed design packages.
The SRF cryomodule team has successfully leak checked and verified the vacuum integrity of the "end cans" that were received last month for the new upgrade cyomodules. The "end cans" are the large structures fore and aft of a cryomodule that delivers and exhausts the helium to the module.
A draft revision of our current DOE/ONR Memorandum of Agreement for the FEL activities was prepared by our ONR contract manager and directed to us and the DOE site office for comments. The current MOA is being revised to encompass new activities that will be funded in FY02 and FY03 including upgrade commissioning, completion of the third cryomodule, design and construction of a new wiggler optimized for 1 micron operation and supplemental hardware projects funded by the JTO. (Note: two JTO projects involving cryogenic mirror design and drive laser design were recently awarded to the FEL project).
Michelle Shinn and George Neil made presentations on our work on laser materials damage studies at the JTO Project Continuation Review on Jan. 8-9 held in Albuquerque
On Jan. 18, we were asked by the Joint Technology Office to send a brief summary report on our FY01 funded activities on laser technology and we responded by the end of the day.
Our co-PI on the AFRL funded UV FEL project, Henry Helvajian from the Aerospace Corp., attended and gave an excellent presentation at this month's LPC Workshop, so we were able to use the opportunity to plan the next quarter of joint activities. We also were able to make some progress on our draft statement of work for the AES CRADA on the 100 mA gun design with Alan Todd’s presence at the LPC Workshop.
We used the LPC Workshop on Jan.17-18th as an opportunity to have concurrent meetings of the FEL Program Advisory Committee and the Industrial Advisory Board. These advisory bodies provide valuable criticism and counsel on our FEL program and plans.
FEL Project management along with the majority of the management of Jefferson Lab was consumed this month by a critical DOE review of the laboratory’s operational budget and budget projections for the next 4 years. The review held on Jan. 22-24 will be used by DOE’ Office of Nuclear Physics to benchmark the costs for CEBAF operations, associated operational support costs, and the necessary costs to keep the lab’s core competencies (i.e., SRF and source technology) viable. Based on the preliminary report given by the review committee, the lab was viewed as a well run and lean operation. In addition, constant effort budgets for the next 4 years would lead to degradations in machine performance and inadequate support of core technologies. Hopefully, this analysis will help DOE enlist Congressional and Administration support for additional funds.
We are pleased to congratulate Old Dominion University, one of our Applied Research Center partners, for successfully soliciting sufficient matching funds from partner organizations to meet the final requirements for a NSF Center for Industry-University Collaborative Research on laser-material interactions. ODU expects to hear an official announcement of the award for the center from NSF next month. We are proud of our colleagues at ODU for this achievement and believe the Center activities will be very useful to FEL users.
The dates have been chosen for the next semiannual review for the FEL Upgrade Project: May 1-3, 2002. There are many conflicts among the review participants that negated the choice of earlier dates in March or April.
Project Cost Performance:
The Phase 1 FEL Upgrade project budget for the period June 1, 2000 to September 30, 2001 is $9,029k. The first phase of the project was fully obligated as of the end of September. The total Phase 1 project cost to date-actual costs plus commitments is $9,029k as planned for Phase 1 completion.
The Phase 2 FEL Upgrade project was approved for $4,500k for a performance period of February 1, 2001 to September 30, 2002. Actual funds transferred from ONR to DOE for this effort in FY02 were $4,442k. Work for Phase 2 proceeded to plan during this reporting period. Actual charges of $353k were accrued for January for total accrued costs of $2076k to date for Phase 2. The bulk of this effort involves procurements of components designed during Phase 1 for delivery and installation in Phase 2. Work scheduled for January was $131k for a total of $691k for Phase 2 to date; work performed for January was $262k for a total of $795k for Phase 2 to date, which results in 15% scheduled vs. 18% performed for the Phase 2 project. At present the cost variance for Phase 2 is -$1281k and the schedule variance is $104k.We expect to meet the planned cost at completion of Phase 2 effort. The program is presently on track to begin commissioning efforts in September 2002.
The UV FEL project was approved for $2,836k for a performance period from September 2001 to September 30, 2002. Efforts were initiated in October with the official project start toward the project deliverables: (1) design of the optical cavity system; (2) design of the UV FEL electron beam and optical transport systems, and (3) production of harmonically generated UV light. Initial program expenditures were directed toward accomplishment of these objectives. Actual charges of $44k were accrued through January for a total accrued costs of $76k since project start. Work scheduled for January was $73k for a total of $261k for the UV project to date, work performed for January was $88k for a total of $276k for the UV project to date, which results in 9% scheduled vs. 10% performed for the UV project. At present the cost variance for the UV project is $200k and the schedule variance is $15k. The program is on track to meet the statement of work requirements on schedule and within the available budget.
WBS 3 (Beam Physics):
Analysis of magnet modeling results continues. 2F and 5F diagnostics configurations were evaluated and appear acceptable. PARMELA simulations are being extended by Hernandez through the linac to provide input to CSR analysis of the IR/UV transport. A report on the latter by R. Li illustrated the intriguing (and very timely) effects of density modulations in the bunch.
Work has started on a skeletal machine commissioning plan. In support of this, an update of the IR Demo Excel machine model was initiated. A few hours of software support for this was provided as a courtesy by an external software consultant; this work may eventually allow definition of the spreadsheet input using via Access databases (i.e., the "right" way) with a significant improvement in model flexibility in the long term.
For example, should we be able to define the machine using Access and use Excel solely as a compute engine, we will benefit from the gazillion man-years worth of error trapping code provided by the Microsoft products, be in a position to use industry standard communication and record update methods in the model, and be able to rapidly switch between different machine setups without tracking multiple spreadsheet versions.
WBS 4 (Injector):
The gun chamber had its top and bottom flanges welded on and the spider locating groove is being machined. Tolerances on the gun stand drawings were loosened up and the package is back out for fabrication bids. The gun mounting ring was submitted to the shop for fabrication. W&M is running a test implant on a 3" diameter tube prior to implant of the cathode support tube. Solenoid mechanical modifications are being designed to facilitate placing correctors inside of the solenoid. The extractor cart drawings are ready for first review. The gun chamber was cleaned and is having its upstream and downstream tubes welded. The rear cross pieces for the gun were machined by the shop; cleaning and welding is still needed. A quote was received for vacuum firing/stress relieving the chamber.
Parts for the rear portion of the cathode shield operating mechanism were completed by the shop, some welding still required. The front end cathode shield assembly was baked to 150C for water removal and still operates fine under these vacuum conditions.
The contract for manufacturing the gun stand was awarded.
Gun Resistors - The resistor, terminal, and coating materials for the conditioning resistor were received Several sample resistors were made this month in order to test the voltage breakdown characteristics of the resistor material with several different protective coatings.
WBS 5 (SRF):
The end can assemblies for the upgrade cryomodule received last month were leak checked and no leaks were found.
WBS 6 (RF):
Quarter Klystrons - All 3 of the 100 kW klystrons were successfully tested at half power with the existing HVPS. Modifications are being made to the klystron cart design to make the piping more compact. The LCW headers in the RF gallery are being modified so larger taps can be installed for the klystrons, circulators, RF loads, and HOM loads. The RF Waveguide Loads were returned to the vendor for upgrading to 100 kW operations.
Quarter HVPS - In less than one day the old 3 phase variacs, transformers, and inductors were removed by a rigging company and the upgrade transformers (3000 lbs.) and inductors (1600 lbs.) were installed in the HVPS's. The schematic for the entire HVPS was reviewed, modified, and turned over to drafting. By the end of the month the drawings were 98% complete. Additional cross-connect data will be added and several new components will be determined prior to release. The installation of the other parts has begun.
A working 50 kW klystron will be used as a load to checkout the HVPS to 28 kV.
Master Oscillator - The upgraded Master Oscillator is installed, connected to zones 3 & 4, and working fine. There are a few diagnostic features that will be added, but this task is basically complete.
2G Dump - With RadCon's permission the water bottles were removed, drained, and stored in their plastic milk cartons. This was necessary before the 2G Dump can be dismantled. This dump is still activated and its removal will require RadCon's supervision.
WBS 8 (Instrumentation):
We removed and rerouted cables in preparation for cable tray modifications to support the new machine. Three of the four changes required to remove interferences are complete.
Six beamviewers have been assembled and delivered to the vacuum group for mounting on their respective pedestals.
The new inventory control and barcoding data base is nearly functional. There are some security items that need to be added before it becomes available for general access.
The design of a new 8 channel Stepper Motor Control Chassis is complete and fabrication has started. All of the control elements for the vacuum system of the IR upgrade were nailed down this month. Nomenclature was changed to maintain the naming standard as set up on the Main Machine and the IR Demo. Updated drawings are forthcoming.
Nomenclature and elements for vacuum, and diagnostic components has been reviewed and drawings updated.
Eleven more ion pump power supplies have been received from the assembler and were inspected.
A wiring problem was noted and the supplies were returned to the vendor.
A new HVPS chassis is being designed. This should replace the three chassis currently in the control room.
Designs are also in the works for an upgraded Analog Monitoring System. The Machine Protection System input card design is nearly complete as well.
WBS 9 (Transport):
Optical Chicane Dipoles (GW)
• I visited Magnet Enterprises International in Oakland CA. They successfully wound a new first coil, bent the ears up
to form the saddle shape and are working on leads and ground wrap. Dimensional checks show no problem with the
coil fitting in the gap, or being larger than the calculated keystone expansion of the bend-up of the ears. Their potting
mold is ready for potting this coil; they will utilize the temperature data from the prototype coil combined with
additional real time temperature probe readings to maintain the required temperature cycle for potting.
• Cores parts are in machining by vendors experienced at grinding and machining magnets made of annealed 1006 steel.
(Several SLAC magnet cores were just being completed at F & F Grinding during my visit.) All other parts are
accounted for by being purchased or by material on order for fabricate in-house.
Injector Dipoles (DU/DV)
• Procurement is continuing via electronic methods. Many vendors have downloaded the web files and registered.
• DULY research, in checking their magnetic model, found that the Small Injector Dipole (GV) field integral quality is a
strong function of the coil saddle ear’s distance from the inner surface of the field clamp’s horizontal plate. (Not so for
the GU larger dipole) It is difficult to maintain tight tolerance on the position of this coil surface. We are being
prudent, asking for a detailed sensitivity analysis. They will alter the drawings to add a shim set on the inside of the
field clamp. Magnet Measurement Folks will be able to alter the coil to field clamp distance to tweak the magnet into
magnetic tolerance by adjusting the quantity of shims.
• All drawing revisions will have to be done by the time we place of the order for these magnets.
Arc Dipoles (GY, GX, GQ)
• Advanced Energy Systems (AES) analyzed the field integral information on the switch mode (to the UV Line) of the
Bend Magnet (GX) along the half sagitta line The field is not exactly half because of better permeability in the return
legs. We will have to shunt current in these two magnets (in the two amp realm) to bring the field down, an easy
solution to the problem. The field flatness and integral seem not to be grossly out of spec and detailed analysis is
continuing. . They also analyzed the Reverse Bend Magnet (GQ) at larger field position and at different levels of
excitation. The vellums of all the drawings are ready for signature and the specifications are in checking. David
Douglas is reviewing their findings.
• Copper was received by Wang NMR of CA for 180 Degree Bend (GY) coil manufacturing
• I visited Wang NMR of CA who is manufacturing the 180° Dipole coils. They are starting to insulate the conductor
and design the winding form and potting mold. I verified that their anticipated winding, potting and curing
methods were realistic for this odd shape coil.
• Measurement of the dipole chamber’s magnetic properties started up using weld samples prepared by the company
that welded the 180 ° chambers last time.
• Design is nearly complete for the probe system to measure absolute field of the Bend and Reverse Bend Dipoles.
3 inch quad (QX)
• Twenty QX Quadruples arrived. We tried to qualify the First Article Quadrupole. However, the magnet measurement
stand didn’t automatically center the quad on the fiducials. We are investigating the cause.
• New England Technicoil has used up all the coils for assembling Quadrupole. They have shipped several additional
batches of ten magnets.
Trim Quad (QT)
• All steel is rough machined and is in annealing. Winding forms are made. Mock up winding should start next week at
Milhous Control of Virginia.
• Tom Hiatt visited Milhous Control of Virginia to have a discussion of critical parameters before actual production
• In the arcs, we were anticipating providing vertical dipole correction field with some windings in the sextupoles. The
3D magnetic model of the Sextupole at DULY Research shows that the superposed vertical dipole corrector field is
coupled to the sextupole field. This is fatal to this concept, which needed a separate 10-pole corrector to correct the
corrector. We will rather make a simple mu metal core corrector to do the task. There may be some beam line space
problems that may force us to split the correction into two magnets, say on either side of the sextupole.
• DULY Research has created efficient field clamps on the sextupole’s magnetic model and met specification at course
mesh. The final design at fine mesh was postponed because of the more urgent need for a re-look at the GV magnetic
• Work on this magnet is on furlough until the sextupole is designed.
Corrector Dipoles (DB, DJ, GC BH)
• No news on qualification of the new sets of Standard Corrector Dipoles (DB/DJ) because the measurement stand is
set up to receive the quadrupoles after being fixed. Before that, the stand’s problems prevented qualification of the
• We will now have to report on the new vertical corrector for the Arcs (GC) in this space as mentioned in Sextupole
• DULY Research successfully magnetically modeled the intended simple new vertical corrector for the Arcs (GC).
• Chuck Hutton designed an IDEAs model of the single set of Haimson style correctors that is needed internal to
the solenoid of the new gun configuration. The coils have to withstand 250 °C bake and have unique mounting
requirements. Jeff Dale of the shop will make them using some very simple drawings from Chuck.
Beam Line and Vacuum
• AES is drawing up the chambers throughout the arcs and is doing finite element analysis of the most
problematic chamber, the chamber at the GX that has the optical cavity through it.
• Design work on girders and stands continued. Parts for the regions between the cryomodules were finally signed off.
• Work is delayed in the 6 quad telescope just before the first arc that was changed by David Douglas with his latest
DIMAD revision. The original positions of the diagnostics (in this region, which was almost ready to sign off on)
were disturbed and we are waiting for Dave to consult about new positions.
• AES continues drawing up the chambers through out the arcs and is completing finite element analysis of the most
problematic chamber, the chamber at the GX in the optical cavity. It mandates a 5/16 inch thick plate.
• Design work on The Optical Chicane region chamber, stands and diagnostics continued.
• David Douglas reviewed and validated his latest DIMAD revision of the 6 quad telescopes just before the first arc
and after the Second Arc. (2F & 5F Regions) that were changed because of UV concerns. He is reviewing the
shoehorning of the diagnostics into the regions.
WBS 11 (Optics):
We received the optical cavity stepper motors with integral PZTs before the end of the year. We’re building a small enclosure so we can preserve the UHV rating and begin testing. We also received ball bearings treated by Dicronite, and we will begin testing them for particulate generation. Review of the drawing package for the optical cavity assemblies revealed a few parts that, with small changes, would yield items that are simpler to fabricate. The revision of the ultraviewer mirror mount has started. We moved the OCCMS work to the User Lab 6 hutch, where we can take advantage of the enclosure to dampen out air currents.
We have devoted some time to eliminating air bubbles in the glue joint for the deformable mirror. By degassing the mixture, we have been able to drop the density dramatically (from ~100 to 3/sq. in.).
The revised drawing package for the optical cavity assemblies has been released for checking. We received the enclosure we’ll use for testing the optical cavity stepper motors. We began working on the design for the insertable mirror assembly that is located immediately after the outcoupler assembly. We began tests with the Ga:In eutectic material we plan to use as a heat conductive medium for the edge-cooled outcoupler mirrors.
Meetings with possible vendors of drive laser components were held at the SPIE meeting in San Jose on Jan 21-24.
We worked with the team doing post analyses on the JTO-irradiated samples, clearing up some ambiguities with the nonmetallic samples. The team is now directing its attention on the metal samples. A presentation on the results was given at this month’s LPC User Workshop.
The mirror mount for the ultraviewer was revised to make it less prone to movement during an undamped excursion; these drawings are in review as well. The optical cavity stepper motors test fixture is assembled and ready for use. The Thompson rails for the optical cavity assemblies were received this month
Answers to questions raised in last month's review of the OCMMS design will be distributed for comment; assuming all questions are answered satisfactorily, we will finish the drawing package. Tests of the new position sensitive detector (PSD) began in the OCMMS test stand. Modeling of a scaled up high power (50kW) laser beam dump, based on our previous design, has recommenced. It will be compared in projected performance and cost with a quote from an outside vendor.
We began procuring parts to build a pulse compressor for the "waste" drive laser IR output. It will serve as a test bed for some of our pulse (both optical and electron beam-induced) diagnostics.
We installed a complete 3" HR deformable mirror assembly (mirror, deforming assembly and heater) into the Mirror Test Stand (MTS). The MTS was carefully realigned to the Nd:YAG laser that will serve as a surrogate for the FEL.
Aerospace Corporation Subcontract on UV Microfabrication
A presentation was given to the January 17-18th meeting of the Laser Processing Consortium (LPC). The presentation described the motivation, goal and development steps that are being undertaken to place a laser microengineering experimental station at the Jefferson Laboratory FEL in two years time. The motivation is to place a user-friendly micromachining station for conducting rapid prototyping experiments in laser microfabrication technology. The goal is to implement this in two years time, for all trained FEL users, starting with the IR FEL. The development steps include the use of the IR FEL as the initial laser source for the experimental station. Visible and UV laser wavelengths will be generated from the IR FEL by the use of non linear optical crystals. The facility is also being designed to directly accept the UV FEL light. Feasibility experiments were conducted to test the viability of generating high average power ps duration visible (~532nm) and UV (~266nm) laser light via the non linear optical scheme. The results were very encouraging from the point of generating ample quantities of both visible and UV light for microfabrication applications. The UV laser light was used to expose a photostructurable glass/ceramic material that is of interest to Air Force space applications. The experimental results show that the ps duration UV FEL should be more efficient at inducing exposure when compared to a similar average power ns duration UV laser. Also, the fact that the non linear optical crystals survived the exposure with the IR FEL Demo suggests that a new low cost supplier may have been found.