IR FEL Monthly Report for July 1997
Navy IR Demo Contract WBS Elements
WBS 1 Project Management
July 1997 was the thirteenth full month for the IR FEL Demo project
funded by the Navy.
Cost Performance Scheduling
We have expanded the discussion of cost performance/scheduling
in this monthly report as the project nears completion.
The original project total available budget was $8,082K. During
August 1996, a funds transfer was negotiated with LANL for $37,645
for an FEL modelling task, reducing the total available budget
to Jefferson Lab to $8,044k. However the project remains scheduled
and measured against the original budget of $8,082k. Any actual
cost comparison has to include the project cost plus the cost
of the agreement with LANL.
The IR FEL Demo project through the month of
July 1997 has a total of $7,636k (less SRF and the building) of
performance scheduled. The work performed through the current
period is $6,844k or 85% complete versus 94% scheduled. The actual
costs accrued through July totals $7,058k. This results in a
negative schedule variance of $792k and a negative cost variance
of $214k.
As of the end of July 1997, $7,827k has been
costed and/or obligated ($7,058 in actual costs and $769 in current
obligations.) The remaining unobligated balance is $217k. A
plan is in place to fully obligate/cost these funds not later
than September 30th. The existing cost variance will decrease
to zero as the schedule approaches completion.
Two months remain to accomplish the remaining
scheduled work of $1.238 million in the project's Performance
Assessment "Earned Value System." To finish on schedule
means that $619k of work, on an average, remains to be accomplished
each month. This represents a decrease of $14k per month over
the June average of $633k. The obligations given do include the
lab's overhead costs.
We expect to complete the remaining scheduled work ($1.238M) at
a cost equal to or less than the remaining budget ($986k, the
sum of current obligations and unobligated balance). The remaining
work is expected to be accomplished for less than the original
earned value assessment when many fractionally complete small
peg points are claimed. In addition, actual procurement and check
out costs for some subsystems will be less than the original earned
value estimates (Apr. 96).
Management
The project team's attention in July was focused on installation
activities. The FEL Building was turned over to the project early
in July. The majority of the injector components from the injector
test stand were re-installed. The cryogenic systems WBS was completed
with the successful cooldown of the transfer lines and the injector
cryounit. Substantial components of the RF and I&C systems
were installed. The linac cryomodule was completed and on Aug.
1 installed in the FEL Facility.
Plans are being reviewed and revised on a weekly basis for integrating
the start-up of FEL commissioning tasks with the completion of
the construction and installation tasks. On July 28th, the DOE-Navy
Memorandum of Understanding was signed for the FY97/98 IR Demo
Commissioning/Upgrade project. Jefferson Laboratory was given
authority to spend $3.7M of funds for this project over the period
of August 1997 through September 1998. Within the scope of the
new project and new project funds are four task areas: (1) Commissioning
Preparations; (2) Commissioning; (3) a second cryomodule system
for an energy upgrade; and (4) design and construction of key
components of a power scaleable (R5) optical cavity. The scope
of the Commissioning Preparations task includes key additions
to the baseline hardware configuration that will allow the IR
Demo to be commissioned with more expedience and with higher confidence.
Prospects for additional near-term funds from the Navy evaporated
in July with the mark-up of the FY98 Defense Appropriations Bill
in the House. No additional funds will be included for the Project
in the FY98 appropriations.
SURA received the June 9-10 MTAC meeting report from Adm. Baciocco.
The committee made recommendations to SURA and Jefferson Laboratory
for dealing with the current lack of Navy support for FY 98 funding
and optimizing the use of the soon to be released FY 97 funding.
Considerable progress was made with internal and external reviewing
of the pre-proposals that have been submitted for initial use
of the IR Demo. We have received 15 of 18 proposals that are
in process. After final review the pre-proposals will be forwarded
to the DOE-BES program office for comments.
Discussions were held with Vice Provost (Calvin Lowe) of Hampton
University concerning relocation of molecular beam epitaxy and
materials analysis equipment to the FEL and ARC Building laboratories.
Our LPC representative from IBM (Jake Pacansky) has arranged for
shipment of IBM surplus vacuum chambers and optical tables for
use in the FEL User Lab.
F. Dylla visited the Vanderbilt Free Electron Laser Facility on
July 18 to continue discussions on research collaborations. Vanderbilt
is currently testing one of our diagnostic systems and discussions
were initiated last year on joint research proposals on laser
materials interactions in the infrared.
Arlene Serber and Jim Palmer, Vice Presidents of Newport News
Shipbuilding's subsidiary, Newport News Nuclear, visited the lab
Monday to discuss continued FEL collaborations between Newport
News Shipbuilding and Jefferson Lab.
At the SPIE Conference in San Diego, CA in July, Rui Li presented
a paper entitled "Shielded Transient Self-Interaction of
a Bunch Entering a Circle from a Straight Path", and Michelle
Shinn presented a paper entitled, "Optical
Design Issues for this Jefferson Lab IR Demo Project".
Jefferson Lab was invited to co-sponsor a Workshop on Scientific
Applications of 4th Generation Light Sources that will be held
on 28-29 Oct. 97 at Argonne National Laboratory.
WBS 5.0 Instrumentation & Controls
A clean area was setup in lab 1 for installation of 1.5 micron
Al foil on OTR beam viewers prior to installation into the accelerator.
The camera mounting frames will also be assembled in the clean
area. Soleniod assemblies are being finished up for the pneumatic
devices. Assembly of the charge-coupled-device cameras for the
electron-beam viewers is also being worked. A collaboration with
Princeton is being investigated, this would entail a loan of their
20 channel cryo-cooled InSb detector array to use the coherent
radiation synchrotron radiation emitted by bunched-electrons to
study and monitor the longitudinal beam dynamics.
Design work continues on the Analog Monitoring System (AMS).
This system is a 128 to 16 multiplexer which routes the desired
signal to either the CEBAF control center over fiber optics or
allows local viewing in the FEL control room with a scope. The
initial design for the front-end buffer boards is complete and
prototyped, this yields a flat response out to 5 MHz from the
RF gallery to the control room. The 3dB point is about 10 MHz.
The backplane design uses previous work done for the beam-position
monitors in CEBAF's Hall B with only a minor modifications. Cabling
and terminations for the clean room in the FEL Facility are complete,
and the photocathode drive laser can now be operated through the
control system. The control room patch panels are installed on
each of the table tops along with scopes and monitors.
Connections for reading the temperature instrumentation diodes
in the cryomodule are in progress. The hardware and software
should be in place by next week. The cooldown diode readout will
use the new servers.
The new servers have their final file configuration and are going
to be used to support the cryomodule cooldown. The ITS server
is still being used to support the injector RF reinstallation
and the initial drive laser recommisioning. The ITS server will
be de-commissioned in early September. Both the CEBAF LAN and
the controls LAN are operating reliably.
The personnel safety system continues to make progress toward
the mid-August operational date. The Machine Protection final
design review material was handed out to the review committee,
the review will be held in August.
The vacuum system hardware is nearing completion, the cables will
be pulled in Aug.
Numerous updates have been made to the web pages: http://www.jlab.org/accel/fel/
documentation/evans/felbair1.html. This site is updated daily
reflecting state of installation and nailing down of details.
WBS 6 Cryogenic Distribution
The FEL transfer line complete. The 1/4 cryomodule (cryounit)
is at 2K with a 65% liquid level. The system is stable and preliminary
investigation shows we are below the heat load budget. This WBS
is now complete.
WBS 7 Beam Transport
Most parts for the 27 dipole magnets (and the parts for the 8
sextupoles) were completed during the month with a few parts
and the coils for the 180 degree dipoles still outstanding. Seven
optical chicane dipoles are on hand. Two styles of Panofsky trim
quad are still in fabrication.
In the corrector area, three mu metal styles are signed off with
only coils for two styles still in procurement with the remaining
parts in manufacturing. Air core correctors resolved to three
styles that are at the latter end of detailing.
In the vacuum system, welded chambers for the x and y positions
and the bodies for optical chicane chambers were completed. The
chambers for the reverse bends and the chambers for the 180 dipoles
are were well started.
The design of arc stands was completed. Design of the recirculation
dump line and a quad telescope on the end of the second arc are
the only outstanding layout design tasks.
Installation activity concentrated on the back leg and the injection
area. Most cable pulling is complete.
Overall summary: dipole measurement, chamber welding and correctors
remain on the critical path.
WBS 8 RF Systems
In the Injector, the waveguides, circulator, and klystron cart
for the first cavity of the quarter cryomodule were installed
and tested for leaks. The waveguides for the buncher cavity were
also installed and leak tested. The Low Level RF racks for the
Injector and Drive Laser were connected to the network and given
preliminary tests. In the Linac, testing of the Low Level RF
control system continued. The full cryomodule was installed and
is ready to be aligned and cooled down. The second spare 50 kW
klystron failed its acceptance test this month. We are waiting
for instructions from the vendor for additional testing and return
instructions. Hipotronics solved the numerous small problems
they had with the 225 kW variable DC power supply. One unit passed
the specification tests, was shipped, and is ready for installation
in the FEL building this week. The other unit was repaired and
is ready for its specification tests. It is expected to be shipped
in August. The 1427 MHz Oscillator and Drive Amplifier for the
FEL Master Oscillator system were installed this month. The master
oscillator distribution cables were connected and preliminary
tests started. Final installation on the LCW supply will be started
in August. The Buncher cavity was installed and aligned. The
buncher water skid and controllers are ready for final installation
and testing.
We have most of the hardware installed for the first 50 kW RF
system and for the 8 kW RF systems. We are starting to make systems
and interlock tests. The gun high voltage power supply gas filled
transmission line elbow inner and outer conductor are now complete.
We are ready to start high voltage breakdown tests. The gun
power supply assembly is complete, the 208 volt feed for the high
voltage driver is installed, and the vessel interlocks are installed.
We will start high voltage testing early August.
WBS 9.2 Injector Move
This WBS is essentially complete except for testing and acceptance
of injector power supply transmission line hardware, and re-connection
of gun-cryounit beam line hardware, and installation of several
components in the drive laser transport line. The drive laser
is fully operational in the FEL Facility clean room.
WBS 9.4 Wiggler
The wiggler girder components were aligned using both the standard
alignment fixtures and using a boresighting technique. The latter
technique guarantees high accuracy but must be calibrated against
the regular methods so that alignment can be carried out with
the system under vacuum. The wiggler girder was then installed
and found to be too high. The support plates were being modified
at month's end. A simplified weld design was attempted for the
wiggler vacuum chamber but it did not work out. The more complicated
old design will be tried out next. The wiggler vacuum chamber
support was fit up. A clearance problem was found and fixed.
The wiggler viewer design was completed. Northrop Grumman agreed
to use its apparatus to carry out a pulsed wire measurement of
the wiggler girder. This will be done in August.
WBS 9.6 Optics
This month was a busy one for installation of the optical transport
in the accelerator enclosure. First, the optical tables were
aligned to within < 1mm of the correct position. We set up
He-Ne lasers to mark the beam path, and then mounted mirror can
stands and mirror cans. In the process, we found the unevenness
of the ceiling necessitated taking stands back down and modifying
them. This accomplished, by month's end most of the mirror cans
were in their final position. We have also received the collimator
and most of it's sub-assemblies, this will be checked out in the
Optics Lab, with installation planned in late August/early September.
Our transport mirror vendor (Spawr) produced a set of incorrectly
polished mirrors, these have been returned. However, we do have
enough mirrors to complete installation of all first-light components,
so this is not a problem. We determined that neither the LCW nor
the HVAC were responsible for the ~ 28Hz vibration the Mach-Zehnder
interferometer detects. The nearest source of vibration are the
motors on the cooling water towers for the CHL, particularly since
one seemed to be out of balance. This has been remedied, so we
will check again at the next opportunity. We began assembly of
the optical cavity assemblies in one of the facility clean rooms,
there have been some delays as the bellows assemblies for the
optical cavity assemblies were cleaned and baked as part of their
processing for high vacuum. We also began testing the accuracy
of the LVDTs on the gimbal mounts. Unlike the linear stage, the
gimbal mount transport seems to have negligible backlash, as reported
earlier. However, we are seeing hysteresis in the LVDT readings.
The problem may be in the way the LVDT was mounted; tests continue.
We received the new style picomotor controller, and it's initial
checkout shows that it is quite nice. We will use it for both
the drive laser optical transport and the FEL optical transport.
In other work, the design of mirror cassettes moved into detailing
phase.
Injector, SRF, Facility, and Other
Activities Outside Navy IR Demo Contract
INJECTOR TEST STAND
WBS 3 - CRYOMODULE
The cryomodule has been completed. All vacuum and helium systems
have been qualified for operational use. Documentation and labeling
of instrumentation has been completed. The cryomodule is ready
for installation into the FEL building on Aug. 1.
Warm Windows
Window production continues on three fronts. 1) The additional
production of the present design has progressed with the completion
of required ceramics with the required machining being performed
at a local shop. Additional flanges have been machined and copper
plated and are ready for final assembly. Final assembly is in
the queue for in-house resources. 2) The windows developed and
manufactured with Northrop Grumman continue to progress. Flanges
have been completed and final braze procedures are being developed.
Final assembly is in the queue for in-house resources. 3) The
cooled waveguide window prototype design is nearing completion.
Some parts are on order and all drawings are being reviewed for
fabrication. Completion of prototype windows is scheduled for
September.
WBS 2 -- BEAM PHYSICS
Additional PARMELA simulations of the beam dynamics from the photocathode
to the wiggler with the present "long" gun configuration
(cathode-anode spacer in place) were done, with the result that
an injector setup was found that gave the short bunch length at
the injection point that was desired for using the interferometric
bunch-length monitors being procured from the University of Georgia.
At "long" bunch lengths, the power from the device
would be "low" and rapidly changing as a function of
the wavelength. Nevertheless, for conceivable bunch lengths,
there is adequate power to perform relative measurements, i.e.,
to monitor bunch length. Cross-calibration to an absolute measurement
made with a back-phasing technique is planned. Analysis of the
data collected during the last series of experiments with the
photocathode gun is continuing. Regarding longitudinal properties
of the 135 pC bunches, the data concerning energy spread versus
longitudinal position, as well as the data concerning bunch length,
agree remarkably well with code (PARMELA) predictions. However,
several issues remain, most notably a disagreement regarding transverse
beam size. Specifically, the transverse rms beam size at the
gun's aperture appears to be much larger than predicted by PARMELA,
and tails are seen to form at the edge of the bunch. Data reduction
continues. Plans are to present the results of these experiments
at the FEL Conference in China next month. The design and associated
beam-dynamics studies of the energy-recovery dump downstream of
the cryomodule were completed and finalized. Various questions
concerning magnet characterization and alignment were investigated
and answered as they arose. This is now a routine activity as
we progress through construction of the machine. Examples included
alignment requirements and procedures for the injection-line quadrupoles,
and the wiggler and wiggler-girder quadrupoles. Details are provided
in weekly reports.
Progress on development of a simulation code that includes the
physics of coherent synchrotron radiation (CSR) is proceeding,
although progress this month was slowed due to our preparation
of related manuscripts for the SPIE Conference held at month's
end in San Diego, CA, at which R. Li presented a paper entitled
"Shielded Transient Self-Interaction of a Bunch Entering
a Circle from a Straight Path", and for next month's FEL
Conference. At the FEL Conference we will present new analytic
results developed mostly this month concerning noninertial forces
that arise off-axis from the design orbit. We also drafted an
extensive manuscript envisioned for submission to Physical Review
E that we will finalize soon after the FEL Conference. Our plans
remain to have the simulation code ready in time to support experiments
planned for the IRFEL early next year.
WBS 4 -- IRFEL COMMISSIONING/OPERATION
We thoroughly scrutinized plans for measuring magnets prior to
their installation in the FEL beamline. The status of procurements,
as well as resource and space limitations for magnet measurements,
are such that some magnets will have to be measured after 1 Oct.
97. We organized the entire process to be compatible with the
commissioning schedule, i.e., with priority on completion of the
injection line, followed by completion of the straight path for
first light, and then completion of the recirculation arcs. We
are anticipating that, on 1 Oct. 97, that the majority of hardware
shown on the system top level drawing will be in place, several
magnets and possibly the vacuum chamber for the second recirculation
arc may be missing, depending on actual delivery dates of this
hardware. On approximately Oct. 1, we will begin commissioning
the gun on swing and owl shifts, leaving day shifts open for installation
activities until they are all complete. Our plan to be pulling
electrons off the photocathode in mid-October, as well as the
timing of the rest of our commissioning activities, remains unchanged.
The top-level procedure for energy recovery was formulated, to
include measurement of dispersion and variation of path length
with momentum from the wiggler to the energy-recovery beam dump.
The process resulted in clarification of specifications for several
pieces of hardware and software necessary for the task. The first
draft of a procedure for fine phasing of the cryomodule was prepared.
The algorithm first determines zero crossings for improved sensitivity,
and then determines crest and anti-crest to check for nonlinearities
and develop some statistics.
The on-line Accelerator Readiness Review (ARR) tracking system
is now about 90% complete. Plans continue to be such that only
one ARR review meeting will be held, in the January-February 1998
time frame, to complete the sign-off of the FEL ARR. Performance
integration plans are under development for the major systems
of the machine. The RF Performance Integration Plan and the Magnet
Performance Integration Plan are completely outlined, and the
writing of their drafts is well underway. Basically, these plans
identify the appropriate subsystem owners and principal investigators
and integrate their efforts toward achieving related specifications.
The process helps ensure test plans required for commissioning
are completely identified and written. The design and operating
strategy for the FEL analog monitoring system (AMS) was finalized.
The AMS will use eight 16x16 crosspoint switches manufactured
by Analog Devices to accept input from 128 lines and generate
output to 16 lines. The switches have built-in BNC connectors
and software to allow PC control that is easily adaptable to the
Lab's EPICS control system. All channels will have a root-mean-square
converter on them with a signal into EPICS, thereby allowing any
of the 128 signals to be archived. The bandwidth of the AMS is
limited to 1 MHz in the Machine Control Center by the fiber-optic
link to the FEL Facility, but in the Facility itself the bandwidth
will exceed 5 MHz. The drawback is that it has no positive verification
of the channel selected; however, there is a calibration signal
and the hardware is commercial, so reliability should be better.
Extensive testing of the system is planned. Successful tests
of the multislit transverse-emittance monitor during experiments
with the photocathode gun led us to consider designing and mounting
one of these devices at the gun's light box as an aid in monitoring
the gun's performance during commissioning and operations. However,
in view of cost and schedule, we are putting this on hold until
we can bring it through design, fabrication, and installation
without stalling higher-priority projects already programmed.
Nonetheless, we are also firming up the projected cost and schedule
for the additional instrument. It is not required for commissioning
but would be a nice augmentation of the baseline diagnostic suite.
Facility
This month the facility became essentially operational. Our locks
went on the doors. The phones went in. The computer networks
became operational. The RF low level controls were cycled for
the first time on a portable computer. The photoinjector drive
laser was placed in the clean room, successfully connected to
the chiller, brought into operation, and connected to the network.
Much optical setup work remains, however. The transport telescope
was hung. Cubicles were placed in each lab to house users and
student researchers. The optical transport line was hung, leveled,
and light brought to the optical control room for the first time.
The injector stands were placed and grouted. The gun was set
in the injector, aligned and hooked up to the light box. The
buncher cavity was positioned as was the injector solenoid. The
wiggler was surveyed on its table to the quadrupoles but placement
of the wiggler table was delayed a week when a hardware interference
was discovered. Magnet power cabling is rapidly going in. Helium
was supplied to the cryounit and cooled the unit to 2K successfully.
The cryomodule was brought to the building and surveyed into
position.
Grounds work is still underway at the facility. The sidewalks
and entrance tiling were completed. Parking areas were constructed
and the street got new asphalt. Piping for LCW, N2, and instrument
air was 95% complete both upstairs and down. Electricians hooked
up a large number of electrical equipment racks. HVAC balancing
continued through the month. Rubber pads were placed in the stairwells
and painting was completed. Punch list work continues on the
facility. The only major items remaining are certification of
the fire alarms and elevator. Both systems are functional but
have some work remaining before acceptance.
The Hilti bolts for the drive laser transport were laid out and
installed. The telescope box was installed and the design of
all the downstairs stands was completed. The two new mirror cans
were assigned to the Jefferson Lab machine shop for fabrication.
All the flanges for the transport line were ordered. All the
optical equipment for the laser clean room was moved into the
facility. The laser was run successfully after several problems
with the chiller system were resolved. The server used in the
ITS was installed in the FEL facility and the laser is now under
computer control. The gun, light box and buncher were installed
and aligned. The interlocks and controls for the high voltage
power supply were wired up and the power supply was ready for
high voltage test in air by month's end.
The drive laser and associated optics and electronics was moved
to the FEL building. New plumbing and utilities have been hooked
up to it and it has been checked out. The electronics have been
placed for the most part in equipment racks and the cabling and
interfacing between it and the VME crates is reestablished. We
had some problems with bacterial contamination in the water, for
the most part that is remedied. We also had problems lowering
the relative humidity to the point where it is safe to set up
the EO modulators, addition of a dehumidifier lowered the relative
humidity to a reasonable level.
Upcoming Meetings and Reviews
International FEL Conference, Beijing, August 18-22, 1997
SURA Science and Technology Review, Sept. 16-17, 1997
Construction Project Close-out Meeting, Oct. 1-2, 1997
Scientific Opportunities for Fourth Generation Light Source, October 27-29, 1997