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).