The advanced light source at Lawrence Berkeley Laboratory—A high-brightness soft x-ray synchrotron-radiation facility

Abstract

The Advanced Light Source, a third‐generation national synchrotron‐radiation facility now under construction at the Lawrence Berkeley Laboratory, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Based on a low‐emittance electron storage ring optimized to operate at 1.5 GeV, the ALS will have 10 long straight sections available for insertion devices (undulators and wigglers) and 24 high‐quality bend‐magnet ports. The short pulse width (30–50 ns) will be ideal for time‐resolved measurements. Undulators will generate high‐brightness soft x‐ray and ultraviolet (XUV) radiation from below 10 eV to above 2 keV. Wigglers and bend magnets will extend the spectrum by generating high fluxes of hard x‐rays to photon energies above 10 keV. The ALS will support an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms. The high brightness will open new areas of research in the materials sciences, such as spatially resolved spectroscopy (spectromicroscopy). Biological applications will include x‐ray microscopy with element‐specific sensitivity in the water window of the spectrum where water is much more transparent than protein. The ALS will be an excellent research tool for atomic physics and chemistry because the high flux will allow measurements to be made with tenuous gas‐phase targets.