Management

Work is underway for a modification of the Jefferson Lab EH & S manual to include FEL activities and procedures. A draft document has been prepared and is undergoing internal review for agreement as to the various procedures to be followed before being released to wider circulation for review and comment and eventually approval on our proposed control documentation and approaches.

Costing estimates for the high power IR/UV upgrade were initiated. All subsystem leaders were given copies of the estimate performed four years ago and asked to update the costs based on IR Demo experience, inflation, change of scope, and available hardware. The first roll up is expected within 2 weeks.

We also worked on presentations and papers for the fast-approaching Particle Accelerator Conference, to be held during the last week of March.

FEL Installation/Maintenance Activities

This week's "installation" activities were predominantly associated with two recesiations of the cathode in the electron gun. In the first attempt the gun would not hold off voltage and a heat cleaning cycle was performed. This was reasonably successful, completing on Thursday afternoon. Up to 40 pC per bunch can be produced which is sufficient for several planned commissioning activities over the next week.

FEL Commissioning Activities

During Swing Shift on Thursday night we continued commissioning tests in User Lab 1 with 12 W fundamental on a gold foil as part of a study of picosecond transients in its thermoreflectivity using the pump-probe technique with the FEL harmonics as the probe.

We are also beginning to bring the FEL autocollimator into operation. This will allow us to measure the optical bunch length in real time using the intensity of second harmonic generation. This work was performed in parallel with alignment activities in Lab 1.

During day shift Friday P. Piot continued performing emittance measurements at the wiggler and in the back leg for systematic studies of beam quality versus machine settings. It includes exploratory measurements to decipher the presence and effects of coherent synchrotron radiation. Work Friday included simultaneous horizontal and vertical measurements to help decipher the impact of CSR.