FEL Upgrade Project December 2001 Monthly Report

Three members of the FEL team were elected as APS fellows this year. Fred Dylla, George Neil, and Geoff Krafft were all honored for contributions related to their work on the IR Demo. Congratulations!

We received the bids back for the fabrication of the largest magnets in the FEL Upgrade-the recirculation dipoles (DY). We are pleased to have received several bids within the price range of our estimated costs.

We thank Charlie Reece for overseeing an effort to Helium and RF pulse process cavity 3 in the FEL injector cryomodule. A significant improvement in the usual gradient was obtained. See the operations section for details.

We are pleased to thank Governor Gilmore and his administration who announced in December a new $1B bond issue for support of higher education in Virginia that includes a $3M line item for the planned addition to the FEL User Facility building to house the compact synchrotron and injector test area. If the bond issue is approved by the Virginia legislature in the upcoming Jan.-Mar. 2002 session and by the Virginia voters in November 2002, then the funding would be available in July of 2003. This same bond issue includes support for many science programs (particularly materials science and bioscience) at Virginia’s research universities that are involved with the FEL user program.

An internal review was held in December on optical cavity diagnostics. See the optics section for details.

We are pleased to note that an article on FELs will appear in the January 2002 issue of Physics Today, written by W. Colson, E. Johnson, M. Kelley, and A. Schwettman. Michael Kelley is with our group and the others are all longtime collaborators.

Jefferson Lab will have a DOE review of our nuclear physics operations budget next month on Jan. 22-24. The FEL project management will be presenting the impact of the FEL project on the lab operations in terms of contributions to maintaining the lab core competencies (SRF and other accelerator physics) and the supporting labor for these efforts.

DOE approved the UV FEL project subcontract to the Aerospace Corporation for their effort toward the design and fabrication of a UV laser microfabrication tool for use with the FEL Upgrade. Our thanks to our PI at Aerospace Corp, Henry Helvajian, our support from JLab business services (R. Lusk and T. Danforth) and our DOE contracting officer, Wayne Skinner, for their assistance in this effort.

We are continuing discussions with Cornell University research staff, who are working on a prototype energy recovered linac x-ray source involving a source current of 100 mA, and with Daresbury Laboratory staff in the UK , who are also working on a next generation light source, about potential collaborations.

Jefferson Lab has a visit on Dec. 19th by several Congressional staff members from the Senate Armed Services Committee for a tour and briefing on the FEL program.

Project Cost Performance:
The project (Phase 1) 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 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 $214k were accrued for December for total accrued costs of $1723k 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 December was $306k for a total of $560 for Phase 2 to date; work performed for December was $266k for a total of $533k for Phase 2 to date, which results in 12% scheduled vs. 12% performed for the Phase 2 project. At present the cost variance for Phase 2 is -$1190k and the schedule variance is -$27k. 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.

Phase 2 has been rebaselined to reflect the following:

1) The drive laser peg point of $100k has been zeroed. That effort will now be performed as part of a JTO development program (WBS 4).

2) The light box has been given an additional $100k peg point in June to reflect the higher complexity of designing a system that will work at the high charges we intend to test in the future with the AES 100mA injector and/or the JTO Drive laser (WBS 4).

3) The $250k SRF effort this year has been deleted and deferred to FY03 (WBS 5).

4) An additional $250k fabrication peg point has been added in June to the 180 dipole fabrication to reflect the higher fabrication costs to meet the tight tolerances and to incorporate the length correction magnets in the same assembly (WBS 9).

5) The total project budget was reduced from the initial authorized amount of $4,500k to $4,442k to reflect the funds actually transferred from ONR to DOE for the Phase 2 activities. The $58k difference between the two project budgets was removed from WBS 9.

Items 1, 3 and 4 were recommended by the Navy/DOE FEL Project Review Committee at the November 8-9, 2001, Semiannual Review. Item 2 is requested by project management for the reasons stated.
1- Management
2 - Facilities
3 - Beam Physics
4 - Injector
5 - SRF
6 - RF
7 - Cryogenics
8 - Instrumentation
9 - Beam Transport
10 - Wiggler
11 - Optics
12 - X-ray
13 - Commissioning
*$100k in WBS 4 moved from WBS 4.3 to WBS 4.1

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 $46k were accrued through December for a total accrued costs of $54k since project start. Work scheduled for December was $187k for a total of $187 for the UV project to date, work performed for December was $83k for a total of $187k for the UV project to date, which results in 7% scheduled vs. 7% performed for the UV project. At present the cost variance for the UV project is $134k and the schedule variance is $0k. The program is on track to meet the statement of work requirements on schedule and within the available budget.

As noted in the management section above, in December we awarded the largest contract in the UV FEL project; a subcontract valued at $881k to The Aerospace Corporation for the design and development of the laser microfabrication end station (processing tool) for use with both the IR and UV FEL.

WBS 3 (Beam Physics):
The UV bypass design is approaching completion. A minor rearrangement was required in the first matching telescope to alleviate geometric aberrations. This change will allow common layouts for the first and last telescopes.

Engineering support focused on "making it all fit". Most of the 10 lbs. of fertilizer appears to be in the 5 lb. sack, but open it with caution.

A mini review of magnet systems checked GW and octopole parameters. They look good.

WBS 5 (SRF):
We received the end cans for the upgrade cryomodule. They will be checked out during January.

WBS 4 (Injector):
The modified cathode shield assembly has been assembled and is ready for testing. Drawings for the shield operator (back end) and the gun stand were signed off and submitted to the shop for fabrication. We completed a high voltage emission test on a stainless steel electrode that was implanted in the re-commissioned plasma/ion implantation system operated by CWM. We are using this test sample and others to benchmark the system before we implant the new electrodes for the Upgrade gun. This test electrode was quiet up to 25 MV/m but started emitting above that level and would not condition out. The ball cathode was final machined (ready for polishing) and had the stock (wafer holder) match-machined to the interior step. The gun stand drawings were signed off and submitted for fabrication bids. Meetings were held this month to help firm-up the tank design. RCD was contacted this week concerning the combined running and conditioning resistors.

WBS 6 (RF):
Injector Klystrons - We tried to recover the spare 50 kW klystron (S/N 007) before upgrading the HVPS to no avail. It appears to arc internally from 7 to 20 kV. It will need rebuilding to make it operational again. The LCW piping on the first 110 kW cart was tested this month. The LCW flow rates are adequate to test the 100 kW klystrons at half power. Larger taps into the building LCW pipes are required for the final installation.

Injector HVPS - The circuit design of the HV section is for the new HVPS is nearly finalized.

An outside vendor has been contacted to remove the present heavy components from the HVPS's and install the new heavy components. Their price is less than it would cost us to purchase the necessary equipment. The HVPS tear-out started on Unit 3. Unit 4 tear-out will start after the klystron tests are completed.

WBS 8 (Instrumentation):
The VME Interface card design is complete and ready for documentation.

Design of new stepper motor control chassis is underway. This will include not only an upgraded version, but additional channels as well. The second Picomotor Mux chassis has been tested and is ready for use when it is needed. Documentation is complete for the new Beamviewer Lamp/Camera Power Supply boxes.

A trip was made to Varian this week to work out response time for their cold cathode controller. The demo unit they had provided for upgrade work and SNS interlocks had been setup improperly. The response time has gone from 8 seconds to 2 milliseconds. Tune into the website for more details: http://laser.jlab.org/sns.

An inventory control system is being developed to support the barcodes that were assigned to components prior to commencing the rip-out portion of the upgrade. This system is nearing completion and will be expanded to include instrumentation chassis, test equipment and other "portable" equipment as requested.

The FLOG system is being enhanced to make it easier to access and provide a search feature.

Cable removal in the vault continues.

WBS 9 (Transport):
Optical Chicane Dipoles (GW)
o  Magnet Enterprises International in Oakland, CA, was under a cure notice on our two contracts, QX coils and GW
    complete magnets. They spent a week concentrating on QX coils because of our request that they have higher
    priority. Work slowed on the GW coil as they also resolved coil form dimensions. The actual potting was delayed for
    a week. In the interim, they started rough machining the core pieces.
o We inspected the initial winding of the first coil as well as bend up fixtures and the potting fixture machining at
    Magnet Enterprises International last week. Potting was observed by our consultant and epoxy expert, Jeffrey Hubrig
    of Innovation Services.
Injector Dipoles (DU/DV)
o  Concerns about the extent of the injector dipole field integral quality in the return beam zone and about the pinch in
    the injector chamber forced by the field clam slider for the wide portion of the dipole. In both cases there seems to be
    no problem. DULY Research magnetic model results indicated the GV Dipoles have specification good field integral
    to the edge of the field clamp sliders. Further analysis indicates that we can also slide the above slider an additional
    3/4 inch with no loss in field quality.
o With the above results and the review of drawings and specifications we did this month, we should be able to sign
    off the drawings and get these magnets into procurement. The requisition is signed and we will do another electronic
    procurement as we did successfully on the 180 degree (GY) Dipoles.
o DULY is almost finished revising small portions of the final assemblies. The specifications are being written to match
    the drawings and revised with what we have learned from our procurements of magnets to date.
Arc Dipoles (GY, GX, GQ)
o  Advanced Energy Systems (AES) is revising the drawings of the pole tips of the Bend Dipole (GX) to reflect the
     magnetic model results.
o Tom Schultheiss of AES is now bringing the Reverse Bend Dipole (GQ) magnetic model in conformance with the
    improvements to the GX
o The responses to our questions on the 180° Dipoles (DY) were received and evaluated.
o The magnetic model of the Bend and Reverse Bend Dipoles (GX & GQ) is being exercised to is being exercised to
    increase the width of the of the good field region per David Douglas’ specification. The GX is nearly through and the
    GQ is starting. The drawings will be revised when the adjustment is over.
Magnet Measurement
o The parts for the dipole measurement stand are being fabricated.
o Measurement of the corrector dipoles continued.
o The parts for the dipole measurement stand are signed off
o We continued work on the probe that will measure the sextupole and the octupole.
3 inch quad (QX)
o The core vender, New England Techni-Coil (NTC) is waiting on our resolution of the quality of QX coils before
    assembling the first article.
o  Jeffrey Hubrig of Innovation Services continued monitoring the production of QX Coils at Magnet Enterprises
    International (MEI), bringing their cure temperature of the coils within epoxy cure guidelines by doing a calibration
    on the oven in a dry run followed by an actual cure per the lessons learned in the dry run. Simultaneously, he reports
    a complete turnaround of the vendor on all issues raised in our previous cure notice. They should be able to
    continue production soon as directed by our Procurement Department.
o The remaining issue of the lowered cure temperature used by MEI on the initial batches of coils was resolved.
    Jeffrey  Hubrig was able to test the epoxy hardness of a series of rejected coils from all the lots. They all registered
    Shore hardness in the 80s while the maximum hardness reported by the epoxy manufacturer is 92 for an ideal cure.
    These strengths indicate that though the cure is not ideal, the strength is substantial enough that the coils will not
    be falling apart or warp during service. We will therefore accept the coils and authorize NTC to start assembly.
o The core vender, New England Techni-Coil is making the final adjustment to the 45 degree chamfer on the pole edge
    of the first article core.
o We resolved the non problem of turn to turn shorts in the coils by unwrapping the copper tubing of the cooling
    circuits. The wrapped configuration was giving false indications of shorts.
o  A second potential problem is being resolved by a thermal test. Sporadic brazing of the tubes to cooling plates on
    the initial series of coils is being compared in a thermal test with coils that have continuous brazing.
o A shipment of 64 fully qualified coils is being readied at Magnet Enterprises International.
Trim Quad (QT)
o The magnets are in fabrication at Milhous Control of Virginia.
Sextupole (SF)
o DULY Research continues to model the sextupole.
Octupole (OT)
o Work on this magnet is on furlough until the sextupole is designed.
o The bids were received and evaluated. The low bidder is being asked to detail a cost breakdown because of the
    spread in the quotations.
Corrector Dipoles (DB, DJ)
o The magnets are being qualified on the measurement stand.
o Milhous Co. is about 6 shy of delivering the entire order DB and DJ coils.

Beam Line and Vacuum
o  Work continues at AES on the design the Arc Chambers.
o  Design work on girders and stands continued. Parts for the regions between cryomodules are being prepared for
o  The layout of the telescope in front of the first arc is complete, accommodating David Douglas’ latest revision that
    works better for the UV line.
o  All the new three leg pedestals in fabrication.
o  Chuck Hutton has drawn up the brackets for the skew sextupoles that we will need at the ends of the Cryomodules.
    He is now working on making a two pair of Haimson like Correctors, suitable for high temperature bake that have to be
    mounted in the gun solenoid. (Haimson Research declined to make a high temperature version of their coils.)
o  Dave Waldman chaired the kick-off meeting to start the task order with AES to design the Arc Chambers.
o  Several sample chambers with the thicker plates necessary for the upgrade have been made to test out the magnetic
o Design work on girders and stands continued. All details of the region between the cryomodules are signed off.
o All return leg girders have been received. All the new three leg pedestals are now out for bid.

WBS 10 (Wiggler):
Commissioning measurements were completed on wiggler 1. Due to the need to divert resources to other tasks, the commissioning measurements on wiggler 2 will be delayed a few weeks. Analysis of the wiggler 1 measurements is ongoing. Magnet measurement scans taken on wiggler 1 to check the corrector values will be used during commissioning and to better verify the vertical trajectory. Analysis work was done on the effect on gain of using the dispersion section at low field. This is the regime where analytical models do not apply. This is quite important for operation at full power. Calculations of the spectrum from the entire wiggler using measured fields are being used to figure out how to set up the wiggler for optimum lasing. The setup for production of X-rays is also being studied as a test case of the tunability. It works differently than expected but it does work. Continuous tunability of the wavelength is possible by keeping the relationship between the wiggler and dispersion strengths fixed on a curve which has been derived.

The vacuum chamber is complete and awaiting completion of final commissioning

WBS 11 (Optics):
The ultraviewer was tested and found to meet specifications. Several parts omissions were found in the drawings, and revisions will be issued. One technical issue (fairly easily solved) will be discussed before the rest of the ultraviewers are assembled.

The detailing of the design for the optical cavities has reached the point where the drawing package for components from the "big C" (the yaw axis yoke) through the mirror holders is now in review. We received the rotary feedthroughs and stepper motors for the optical cavity assembly y-axis motion. The ball bearings for the leadscrew have been cleaned for high vacuum use. They appear to be usable as-is. Because of the low cost and potentially high payoff, one pair is going to be coated with dicronite and then evaluated for particulate generation. Purchase of the rails and pillow blocks for the optical cavities (plus spares for the test stand) are in procurement.

The OCMMS tests continue. The new position sensitive detector arrived. An internal review of the OCMMS beamline hardware revealed a possible susceptibility to mirror movement due to power absorbed from the FEL harmonics. We are redesigning that part.

Discussions with a potential vendor for the drive laser were held. We received an updated budgetary quote from a vendor on the ultrafast laser. Calculations and planning continue on enhanced FEL pulsewidth diagnostics.

Thanks to J. Gubeli's efforts, all FEL optics associated with the optical cavities have been removed and are either stored in User Lab 2 or are awaiting survey by RadCon. Before disassembly, a videotape with narration was made. All of the turning mirrors were removed, their orientation marked, and their flatness measured with the Wyko laser interferometer for later analysis. We removed, disassembled, and stored for later use the optical transport system beamtubes.
S. Benson removed the lightbox yoke and stored the associated components. The piece of drive laser optical transport that places the Brewster window close to the light box was removed.

Operations/Decommissioning/Other Activities:
From C.Reece's report of RF conditioning of the injector cryounit:
A note describing the recent test of pulsed rf helium processing on FEL I-3 is available in DocuShare at: http://docushare.jlab.org/Get/File-4729/Pulsed_rf_helium_.pdf

The cavity showed significant improvement with cw processing and also subsequently with 2 ms pulsed processing. In pulsed mode the cavity was limited by prompt arc trips at 17.5 MV/m. In cw mode, the cavity was limited to 15 MV/m by IR trips. It was initially limited by field-emission induced quench at 12 MV/m. Operationally, it has been limited to ~9.2 MV/m by field emission loading. It now appears quite usable to at least 13 MV/m.

Aerospace Corporation Subcontract on UV Microfabrication Tool Design
The project was formally initiated December 12, 2001 and a Job Order (JO) issued on December 18, 2001. An internal kickoff meeting was held to identify the critical technical lead personnel and discuss the project in overview prior to adjourning for the Christmas/New Year Holidays. A work breakdown schedule has been prepared with 9 major identified subtask areas. All personnel are members of the Laboratory for Laser Microengineering Science/The Aerospace Corporation. Frank Livingston is the technical lead for two subtasks (Optical –1, Process Development –6), Dan Harps will assume the technical lead for (Pattern Transfer (CAD-CAM) & Process Control –3, and User Support –7), Bill Hansen will be technical lead for two tasks (Metrics, Documentation, Safety –5, Vision System –4) and Henry Helvajian will assume the technical lead for two tasks (Project Management –9, Motion Control –2). A technical lead for Tool Maintenance (-8) is premature as we are in the design phase of the project. It is intended that the four subtask leads will work in close collaboration during the design phase of this project. Finally, a meeting was conducted with The Aerospace Corporation Safety Office to acquaint them with new project in general overview and to identify potential safety issues and concerns.