The 'Super-ASHURA' KrF laser system is currently under development at the E
lectrotechnical Laboratory. An electron-beam pumped large-aperture KrF lase
r amplifier named 'Amp4' has been completed and is operational as the main
amplifier. Amp4 and the currently operating 'ASHURA' pre-amplifiers (660 J,
six beams) have been combined to form the upgraded system. Laser energy ex
traction experiments from Amp4 have been started (2.3 kJ, 12 beams). (C) 19
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