Nearly Monochromatic Lasing at 182 Å in Neonlike Selenium

Abstract

The $J\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0\ensuremath{\rightarrow}1,3p\ensuremath{\rightarrow}3s$ transition at 182 \AA{} in neonlike selenium is observed to completely dominate the lasing output, as predicted but never observed before this work. Instead of a single long pulse we use a series of short 100 ps pulses from the Nova laser to illuminate slab targets of selenium. The 182 \AA{} line is more than an order of magnitude brighter than the usual 206 and 209 \AA{} laser lines. Similar behavior is observed for neonlike ions of germanium, zinc, and nickel.