This week's activities involved running high-average-current beam to the straight-ahead dump and doing parametric studies of the transverse emittance at the exit of the cryounit using one of the multislit diagnostics. As of this writing (1150, 10 April 1998), we are running 38 MeV beam at about 1 mA stably. With 60 pC bunch charge, the nominal normalized transverse emittance at the exit of the cryounit was measured to be about 6 mm-mrad in both the horizontal and vertical directions. By comparison, PARMELA simulations predict 3.5 mm-mrad. Basically we are off to a good start, but as noted below, we still need to decide how to optimize the injector setup and what constitutes an adequate setup. The answer lies ultimately in the beam quality at the entrance to the cryomodule, and it awaits availability of both the multislit diagnostic and bunch-length monitor at that point. The week's activities also permitted us to verify operability of all of the beam position monitors and the current-monitor cavity on the straight-ahead machine.

There is concern about alignment of injector components. This week we moved the second solenoid down about 0.5 cm which enabled us to center beam through the buncher cavity, both solenoids, and the cryounit. Before moving the solenoid, we could not center through it but could center through the other components (or so it appeared). C. Bohn will set up an off-line meeting to identify key measurements that will lead to resolution. All agreed that we need to harden the injector setup and then "not touch it".

There was some discussion about next week's shift plans. As it stands now, we will run sustained high cw current (hopefully 1.1 mA) to the straight-ahead dump for three reasons: to monitor cathode lifetime systematically, to watch for infant mortality, and to ensure our high- power RF systems stay stable, especially the "8 kW" cryomodule klystrons. We also have extensive time dedicated to diagnostics checkout next week.