X-ray laser facility at the PALS centre

Abstract

A new laser centre called PALS, first presented at the preceding X-Ray Laser Conference in Kyoto, is up and running and is now available for users. In this paper we review in detail the completed facilities and instrumentation related to experiments on X-ray lasers and on their derivative applications. The target area is equipped with a tandem of vacuum interaction chambers, designed to feature typical geometries encountered in X-ray laser experiments and to make it possible to relay the X-ray beam at distances of several meters. The amplifying medium of lengths of up to 30 mm will be driven by the separately delivered prepulse and main pump beams. The basic hardware available for the X-ray laser experiments includes an opto-mechanical target assembly, an automated half-cavity, and diagnostic devices for monitoring the plasma column and for temporal and spatial characterisation of the amplified soft-X-ray radiation emerging along the plasma axis. The attainable target irradiance of up to 6×10 13 Wcm -2 for 400-ps long pulses will allow us to investigate a number of collisional excitation neon-like lasers, while the neon-like zinc emitting at 21.2 nm will be the basic system for the designed early applications. These include interferometric probing of solid surfaces subjected to strong electric and laser fields, employing both Fresnel and Lloyd X-ray interferometers. Finally, we briefly outline two major upgrades of the PALS laser. These include adaptive optics which have prospects for increasing the shot rate and boosting the focused intensity, and an OPCPA-based system for generation of ultrahigh peak powers.