Performance of the large aperture module of the Aurora krypton fluoride laser system

The large aperture module (LAM) is the final amplifier of the Los Alamos Aurora krypton fluoride (KrF) laser system.1 Ah artist’s conception of the device is shown in Fig. 1. It consists of a laser chamber with a 1-× 1-m aperture and a 2-m active length which is directly pumped by opposing 1- × 2-m electron beams (up to 675 kV at 20 A/cm2). Each electron gun is driven by two 2.7-Ω water pulse forming lines (PFLs) connected in parallel. The PFLs are each 10.7 m long giving a 650-nsec pump pulse. Each pair of water lines is pulse charged by a Marx generator capable of producing up to 1.8 MV. A pair of Helmholz coils is provided to prevent beam pinching in the diodes and to ensure uniform pumping in the laser gas volume. The laser chamber can be filled with up to 1.5 atm of an Ar/ Kr/F2 lasing mixture.