|
|
To:
cc:
From:
Subject:
Date:
|
|
J. Cook, D. Helms, W. Skinner
Division (M7), FEL Coordination Group
F. Dylla
IR Demo Project Weekly Report, July 27-31, 1998
July 31, 1998
|
|
|
|
|
Management
Highlights for the week include the following: we reestablished operations last Friday afternoon
after publication of last week's report. Despite having to run the gun at sub-par performance
levels, the week's accomplishments were commendable. We threaded electron beam around the
remainder of the machine for the first time and achieved energy recovery at low duty cycle while
lasing. In preparation for a subsequent demonstration of cw energy recovery, we attempted to
optimize the cw laser power with straight-ahead operation at 1.1mA and achieved a new record
average power of 311 watts.
|
|
|
|
FEL Commissioning Activities
This week saw the achievement of three notable FEL accomplishments: (1) recirculating pulsed
beam (60 pC @ 2 Hz and 18.7 MHz, yielding a 1.1 mA average current over a 200 µs macropulse
length) all the way around the recirculation loop while recovering energy from the macropulses
(which means beam was taken through the entire machine), (2) lasing with this beam while
maintaining energy recovery from the macropulses and keeping the beam squarely on the viewer
in the energy-recovery dump, and (3) lasing into the straight-ahead dump to achieve 311 W cw. S.
Benson authored the following summary of the straight-ahead lasing activities:
Lasing with the high-power (90% reflectivity) mirror set was characterized this week. First, lasing
was established and optimized using the steering, cavity alignment, buncher gradient and
cryomodule gang phase. It was found that the optimum orbit through the wiggler and the optical
cavity alignment was close to that obtained using the setup procedure. The optimum buncher
|
|
1
2
