Characterization of BG28 and KG3 filter glass for Drive Diagnostic Attenuators

Page, R H ; Weiland, T ; Folta, J

Lawrence Livermore National Laboratory

关键词: Luminescence;    Absorption;    Buildup;    Kinetics;    Simulation;   

DOI  :  10.2172/924016
RP-ID  :  UCRL-TR-237012
RP-ID  :  W-7405-ENG-48
RP-ID  :  924016

美国|英语

来源: UNT Digital Library

【 摘 要 】

BG28 and KG3 filter glasses were tested for use as attenuators in the NIF drive diagnostic (DrD) systems. Tests were performed in the Optical Sciences Laser facility with a 351 nm, 2-step, 3-nsec pulse at fluences ranging up to {approx} 1 J/cm{sup 2}. Single-shot measurements showed no solarization when the samples were allowed to relax for a week after exposure. KG3 filters exhibited no luminescence and no transient pulse distortion. BG28 filters luminesced appreciably and imposed a 'droop' (similar to 'square-pulse distortion') on the signals. The droop parameter is estimated at 0.50 {+-} 0.11 cm{sup 2}/J. Droop is explained in terms of known copper-doped-glass spectroscopy and kinetics (buildup of triplet-state populations, with excited-state absorption). Simulation of the distortion ({approx}1.6%) expected on a 1.8 MJ Haan pulse led to a minor redesign of the Drive Diagnostic with reduced fluence on the BG28 filters to reduce the droop distortion to 0.5%.