FEL Upgrade Project Weekly Brief
October 16-20, 2000


The FEL was used this week for two interesting sets of experiments: (1) the production of carbon nanotubes, and (2) a test of efficacy of 2.94 micron radiation for corneal ablation.


This week was dominated by the final preparations for next week’s semi-annual review of the FEL Upgrade Project on Monday, Oct. 23.  We are looking forward to presenting our progress to the review committee which served us so well for the project kick-off in June.

We completed the project financial reports for September so that the review committee can be presented with a complete set of data for the first four months of the project.  All WBS elements have nearly caught up to where they should be according to the project plan despite the two-month delay with the start of the project on June 1, 2000.  The only exceptions are the RF systems which are considerably ahead of schedule and the optical systems which are slightly delayed until we have the conceptual design reviewed at the Oct. 23 project review.  Because of the favorable record with the RF systems the overall project is %16 complete as of Sept. 30,2000 vs. %13% scheduled.  The project is currently carrying a positive schedule variance of $235k and a positive cost variance of $380k.

WBS 3 (Beam Physics)

Design modifications allowing integration of a UV bypass with the IR Baseline was completed and a layout sent to engineering. A picture providing a sketch of IR & UV in the vault is attached. The design will be documented in a forthcoming JLab Technical Note.

WBS 4 (Injector)

We ran 5.5 hours of data on the N2 implanted electrode at 30 MV/m. The current averaged about 50pA with a small amount of activity once in a while which could be conditioned out. This is very encouraging results
for use of this treatment for the upgrade gun electrode design.

We discovered that a lead was disconnected internally in the thin film monitor that we plan to use to test the aperture cesiator.  We are sending it back to the manufacturer for repair.


A letter of intent was sent to KEK which indicates Jefferson Lab’s interest in the KEK proposal to electropolish the FEL Upgrade cryomodule cavities in exchange for test data on the cryomodule performance in the FEL.

WBS 6 (RF)

All 8 Klystrons were installed in zone 4 this week and the filament circuits were tested. A klystron was replaced in zone 2 cavity 5.  It was starting to have high Mod Anode current and overheat which leads quickly to klystron failure. The RFP was issued to upgrade the HVPS for the 100 kW klystrons. The requisition to upgrade the Gun HVPS was signed and sent to Purchasing.

WBS 8  (I & C)

The Laser Safety Systems (LSS) have been gone over in agonizing detail, there were very minor differences in some of the local Programable Logic Controller (PLC) boxes, and hence unique code. The code from lab one was installed in the other "hutchless" labs and the minor changes were done to bring all units in agreement to the drawings. The logic in lab 3 is unique since it has a hutch. All four labs passed all of the requirede certifications. The user lab patch, pico-motors, and lAN are all nearing completion.

Additional progress was made on the vacuum control system, and on DC power. The BPM RFP should go out next week.

WBS 9 (Transport)

We continued generating the GW 3D layout. We continued making the magnetic model of the GX.
Quadrupole - QX (3.125" Quad)
Prototype Fabrication: Aluminum sample of quadrant was found to have a 0.002 inch offset.
Budgetary Quote: Everson has given us a budgetary quote on the 3 inch bore quadrupoles that is considerably higher than our budget, mostly in the core manufacture.  This validates our original intent to machine the
core quadrants on our own new computer controlled milling machine on an off hours basis to bring machining costs down.
Our radiation expert is continuing to calculate the reflected radiation from severely tilted dump faces.

WBS 10 (Wiggler)

The dispersion section contract has been awarded to PECO. Delivery is expected before the end of the December.

WBS 11 (Optics)

One O-BPM's mechanical assembly was installed in the accelerator enclosure.  A mechanical interference prevented installation of an O-BPM assembly in the Optics Control Room (OCR).  We have modified a section of beam transport tube to remove the interference, and the assembly will be installed over the weekend.

A contract was awarded to Advanced Energy Systems to complete the deformable mirror design we plan to use for the HR mirror.

Michelle Shinn attended the 32nd annual symposium on optical materials for high power lasers (aka The Boulder Damage Symposium).  This is one of the best forums for learning the latest improvements to the
robustness of laser components to optically-induced damage.  Also visited were two optical vendors we have used in the past; Rocky Mountain Instruments and Alpine Research Optics in order to acquaint them with our optics requirements.  Both companies are interested in continuing to work with us.


We had a successful set of user runs this week after re-configuring and re-certifying our laser safety system (LSS). We then provided 3 micron beam to a group from William and Mary, NASA and Penn State to produce a sizeable amount of carbon nanotubes in both cold and hot cell configurations. Following that effort a group from Duke investigated reduction of collateral damage in corneal ablation tests at 2.94 microns.  These were our first tests on biological samples.  Both groups will have follow-up experiments next week under 6 micron conditions.

In a one-day experiment last Friday, Thomson scattered x-rays at 12.7 keV were detected for the first time using 3.1 micron IR FEL radiation.  Our previous FEL generated Thomson x-rays - at 5.12 keV - were produced using 5.1 micron light. This run clearly demonstrated capability the Jefferson Lab's FEL to produce Thomson x-rays simultaneously with IR AND over a broad tuneability range.