ABSTRACT
This paper presents investigations on x-ray lasers with the use of laser-irradiated gas puff targets. The gas puff targets were created by pulsed injection of gas from a high-pressure solenoid valve through a nozzle in a form of a long slit. The hot plasma column to be used as an x-ray laser active medium was produced by irradiating the gas puff target with a high-power laser beam focused to a line. The x-ray laser experiments were performed at Garching using the Asterix IV high-power iodine laser. X-ray lasing with neon-like argon and nickel-like xenon ions were observed for the first time,
