MEMORANDUM
To: J. Cook, D. Helms, W. Skinner
cc: Division (M7), FEL Coordination Group
From: F. Dylla
Subject: IR Demo Project Weekly Report, March 2-6, 1998
Date: March 6, 1998
Management
Highlights for the week include: (1) completion of re-assembly
of the photogun and start of its bake-out cycle; (2) completion
of the east arc vacuum work and subsequent pump-down (the entire
machine is now under vacuum except for the west arc); and (3)
start of the optical cavity longitudinal alignment process.
With the schedule determined for re-assembly and start-up of the
photogun, the near-term commissioning schedule was redone assuming
start of operations on March 16th. A meeting was held with all
concerned with the GEN target irradiation procedure to finalize
the schedule for target installation, irradiation and removal
before the end of March.
We have worked with Eric Rohlfing in the DOE-BES program office
to develop a set FEL specifications and capabilities that would
be of interest to the chemical physics community. The input data
has been approved by Eric. We plan to post the data on the FEL
WEB site for use by a chemical physics working group who will
be meeting later this month at the ACS meeting in Dallas.
Two candidates for a W&M professorship in atomic/molecular
or condensed matter physics visited the lab this week for interviews.
The successful candidate is expected to have an active research
program with the FEL.
On Friday, March 6, Bob Barker, a program manager at AFOSR, visited
the lab to discuss interactions with the Applied Research Center
and the FEL. Mr. Barker's interests are in high pressure plasmas
and plasma diagnostics and currently funds work done by Prof.
Karl Schoenbach, our LPC representative at ODU.
Installation Activities
The raster magnets and power supplies for the 2G dump and GEN
targets are installed and were made operational this week.
The high temperature bake cycle for the gun was started today.
The first 180° bend vacuum chamber was installed in the 3F
region. The instrumentation is in the process of being setup.
The 2F (wiggler and optical cavity), 2G (straight ahead dump),
3F (west arc), and FEL Optical Transport lines to the Optical
Control Room were pumped down this week.
The alignment of the Gun was checked this week. The first critical alignment of the Optical Cavity was started this week and will continue next week.
Testing of all cavity HOMs and microphonics continued this week
in the vault. A cavity tuning algorithm (P-Tune) was run without
the drive laser operating. It will be run again next week with
the drive laser operating to check for any problems.
The insertable dump and the DQ vacuum chambers were installed
in the west arc, but the beam pipes were not connected.
Two work stations were installed in the MCC for standard operations.
The video cables for 2 monitors are operational in the MCC building
and are ready to be run into the control room.
The installation of a Laser Safety System (LSS) for User Lab Room
4 was completed. A smart card is used to gain access to the room.
The ground water leaks in the front and back stairs of the vault
appear to be fixed.
Commissioning Activities
The week's commissioning activities have principally centered
on readying the photocathode gun and planning for expeditious
irradiation of the GEN targets in support of the nuclear physics
program. Gun preparations are proceeding well, and today we started
baking the gun. Plans remain to turn on the machine at swing
shift Sunday, 15 Mar 98. We will then get tune-up beam (2 microamps,
38 MeV) to the straight-ahead dump, install the GEN target chamber,
irradiate three GEN targets, then deinstall the target chamber.
This should all be completed by 27 Mar 98, after which our activities
will be focused on achieving first light.
A considerable amount of data was taken this week concerning higher-order
modes and microphonics in the cryomodule, and we are in process
of assimilating the data.
There has been a considerable amount of ongoing effort oriented toward making machine commissioning easier. For example, this week we had a second session of "FEL Training", we have been posting on a newly created www "FEL operator page" snapshots of the beam on the viewers as calculated with PARMELA, and we (specifically Dave Douglas) have been refining an Excel spreadsheet code for convenient calculations of beam dynamics in the linear accelerator (i.e., post-injector beam dynamics).