We were pleased to provide the local arrangements for the JTO sponsored workshop on “High Power FELs for
Naval Applications” that was held this week in Newport News. Over 120 participated. The conference
summary will be prepared by the workshop chair, Alan Todd from AES after he sifts through the output of the
four working groups. The bottom line: there appears to be a credible development path for 100 kW and above
based on the FEL concept demonstrated with the 1 and 10 kW Demos at Jefferson Lab. Such a program will
benefit from DOD experience with other high energy laser systems and the DOE accelerator programs which are
continuing to develop relevant electron sources, acceleration systems and RF power systems.
Management attention was totally consumed by the June 5-6 JTO workshop and the follow-up FEL technology
Area Working Group meeting chaired by Eli Zimet on Thursday, June 7. Most of the independent review team
responsible for the semiannual reviews of the FEL Upgrade project attended both workshops so we were able
to provide an interim view of our progress to review team members. Also attending the workshop were eight of
Bill Colson’s students from the NPS. This provided a good kick-off to the NPS studies of FEL performance
and possible resonator enhancements.
WBS 3 (Beam Physics):
Design team members participated in the Navy high power FEL workshop. It was entertaining, particularly when
the "ship" guy said, essentially, "consider a cubical FEL". 1 MW looks, however, within the realm of reason,
and, with proper coaxing, the upgrade (with a completely new injector and using appropriately configured 7-cell
linac SRF) might someday run to near MW class.
Technical activities centered on analysis of ancient (Oct 1999) difference
orbit data. Reasonable agreement
between model and measurement is being achieved. This is unfortunate, because the difference orbit data results
are anti-correlated with predictions & measurements of BBU thresholds. Oops. More to follow.
WBS 4 (Injector):
Kovar rings have been welded into flanges and the mid-voltage ring, waiting for leak checking. The shop is
ordering pipe and tubing for the gun chamber. The gun stand and a handling device for the ceramic stack are
WBS 5 (SRF):
Space frame and vacuum vessel punch list generated with vendor. Planned delivery for both 1 July.
WBS 8 (I&C):
Lots of LSS work. The wiring of the hutches in labs 3 and 6 has been finished and all necessary limit switches
and smoke detectors installed. The Low Level certification of all labs is complete. James and Dan assisted with
the Alignment Mode certification as well.
James set up a video system for the experiment in Lab 3.
OBPM testing continues. James is finishing the drawing of the daughter board to take to EECAD.
Two significant additions were made to the website this week.
All FEL Drawing numbers can now be located on
the web. A search function allows searching by drawing number, title, or drawn by name. All user lab phone
numbers are also posted on the website. Future uses may see experimenters listed by name as they are using the
Bids are in on the assembly of the Ion Pump Power Supplies. They
will be shipped out for assembly early next
The front panel for the new VME Timing Circuit has been ordered expected delivery date is early July.
Drawings in EECAD: IPPS Main Board Schematic; MPS System Drawing;
Analog Differential Driver Board;
Pyro-Electric OBPM Buffer/Amplifier; Picomotor Relay Chassis Wiring Diagram; VME Timing Module
Schematic, Fabrication and Assembly; LSS User Shutter Control Box Wiring Diagram
WBS 9 (Transport):
Injector Dipoles (DU/DV)
o The drawings of both magnets are being checked.
Arc Dipoles (GY, GX, GQ)
o Advanced Energy Systems completed design of the leads, manifold and cover of the Arc Bend Dipole (GX).
o In magnetic modeling, a change in the BH Table to the material in the Lab's TOSCA program extended the
length of the good field region such that the start of the end field roll off matched the roll off of the IR Demo Dipoles
when scaled for the larger gap. Earlier work convinced us that this BH Table matches the 1006 Steel and
annealing procedure contemplated for these magnets. AES has constructed a model that exactly matches our
TOSCA model of the earlier Preliminary GX without the UV switching region. This effort will bench mark the
agreement of the two codes. They are also evaluating the model that has a Purcell gap and electrical steel
applied to the pole surface to attempt to flatten the field.
QX (3 inch quad)
o The coil manufacturing bid was accepted from Magnet Enterprises International of Oakland, a firm that made
the IR Demo quadrupoles.
o The core procurement package remains out for bid.
o We continue cuts on the chamfers of the ends of the poles to reduce the n =10 pole.
QT (Trim Quad)
o Design work continued.
o Robin Wines constructed the 3D model in TOSCA. An integrated vertical dipole creates an excessive 10 pole.
The preliminary decision about how to integrate the vertical corrector dipole into the magnet style that meets
David Douglas’ specifications is to hang a thin, separate 10 pole correction element onto the 4 sextupoles that
o We had to submit some additional thickness information to the company bidding on the Dipole Steel to clarify
the flatness tolerance for the slabs.
o We continue assembling the attachments for the task definition to be used by an engineering service contractor
for design of the arc chambers.
o The requisition for the copper for all the dipoles was sent to Procurement with a sole source justification.
WBS 10 (Wiggler):
The correction coils for the wiggler are being wound. The first one was completed this week. The tubing for the
vacuum chamber has been received and the machine shop is making up test pieces to test the welding technique.
Mike Beck has been assigned to manage the fabrication of the chambers. No progress on the measurement front
due to the loss of the engineer for magnet measurements.
WBS 11 (Optics):
The optical cavity assembly design has progressed in the following areas: The changes to the internal component
attachments were made to the drawings. Component definition continues. We have begun setting up a test stand
for the mirror metrology system. We are receiving components for the ultraviewers, part of the alignment system.
The following work was done this week to support Operations: Installed
new lamps in the drive laser, and
reinstalled curtains. Assisted in the certification of user labs. The broadband (5.0 - 6.6 um) outcouplers we
received last week passed inspection.
I prepared for, and gave a presentation at the Navy/JTO conference.
We also devoted time to calculations/
modeling to support our JTO-funded research, as well as specifying and purchasing some equipment to support
some of the diagnostics.
We completed the low level certification of the LSS for all the user labs and the OCR, also completed the high
level (final) certification for Labs 1 and 3 and the OCR. On Friday we started up the machine by reloading
saved files and easily achieved 450 watts cw at 3 microns. We completed the first user run for the nanotube
group. They will be back for more beamtime on Monday and Tuesday of next week.