To: J. Cook, D. Helms, W. Skinner

cc: Division (M7), FEL Coordination Group

From: F. Dylla

Subject: IR Demo Project Weekly Report, January 4-8, 1999

Date: January 8, 1999

Management

The IR Demo has been shut down for maintenance/installation activities since before the Holidays. This maintenance period is coincident with a shut-down period for the main machine. We expect to bring the machine back on-line during the week of Jan. 25th.

Preparations continued this week for presentations that will be made before the DOE (BESAC) Panel on Novel and Coherent Light Sources on Jan. 19-21, in Gaithersburg, MD. In addition to a description of the JLab FEL program, science applications of the FEL will be discussed by Prof. Bill Cooke (CWM) on atomic physics, Prof. Kevin Lehmann (Princeton) on chemical physics, and Prof. Len Feldman (Vanderbilt) on materials science.

Discussions continued with representatives of Northrop Grumman and Advanced Energy Systems, Inc. on a collaborative effort for upgrade of the IR Demo to higher power levels.

Installation/Maintenance Activities

Good progress is being made with gun maintenance activities. A new cesiator was prepared and is being baked this week. A new photocathode and new residual gas analyzer will be installed in the gun next week according to schedule.

Several new diagnostic systems are on track for installation this shut-down. Beam current monitors have been installed in the 4F and 5F regions. The multislit diagnostic for the injector (1F) region has been re-machined with a smaller slit and is ready for re-installation.

A major activity for this shut-down involves placement of RF screens over the IR sensors in the RF couplers in the cryomodule. Both the IR and phototube detectors that are installed on RF power couplers protect the warm/cold RF windows from excessive heated and/or arcing. These sensors have been affected by HOM power as we pushed the recirculation current above 1 mA. If the screens do not solve the problem, gatevalves will be added to the IR sensor ports on three cavities during this shut-down to allow other solutions to be investigated. The FEL cryomodule will be warmed-up this weekend, the modifications performed next week, followed by cool-down next weekend.

Commissioning Activities

A draft Laser Operations Safety document for User Lab 1 has been completed and reviewed by the lab's laser safety officer.