The Advanced Light Source (ALS) is a specialized particle accelerator that generates bright beams of x-ray light for scientific research. Electron bunches travel at nearly the speed of light in a circular path, emitting ultraviolet and x-ray light in the process. The light is directed through about 40 beamlines to numerous experimental endstations, where scientists from around the world (“users”) can conduct research in a wide variety of fields, including materials science, biology, chemistry, physics, and the environmental sciences. Operation of the ALS is funded by the U.S. Department of Energy, Office of Basic Energy Sciences. It cost $99.5 million to build.
The wavelengths of the synchrotron light span the electromagnetic spectrum from infrared to x-rays and have just the right size and energy range for examining the atomic and electronic structure of matter. These two kinds of structure determine nearly all the
commonly observed properties of matter, such as strength, chemical reactivity, thermal and electrical conductivity, and magnetism. The ability to probe these structures allows us to design materials with particular properties and understand biological processes inscrutable to visible light.
Most recently, advances in accelerator design have made it possible to construct diffraction-limited storage rings (DLSRs), where the electron beam size is comparable to the wavelength of the light emitted. According to preliminary studies, a DLSR upgrade of the ALS (ALS-U) modifying the ALS magnetic lattice and injection process would vastly improve brightness, coherence, and resolution. On September 27, 2016, ALS-U received “critical decision zero” (CD-0) status from the U.S. Department of Energy, the first milestone in a path forward that will allow a 23-year-old facility to maintain world leadership in soft x-ray science for at least another 20 years.
What projects do they work on?
The upgrade project, known as ALS-U, will boost the brightness, focus, and other properties of the light beams produced at the ALS.
The ALS is a type of synchrotron: It creates and accelerates powerful electron beams that emit light as they travel around bends. This light, which ranges from infrared to X-ray wavelengths, is channeled to dozens of beamlines, where it is used to explore a variety of sample types at microscopic scales for experiments that span from materials science and chemistry to environmental science and biology.
The Advanced Light Source is a U.S. Department of Energy (DOE) Scientific User Facility supported by the Director, Office of Science, Office of Basic Energy Sciences and operated for the DOE Office of Science by Lawrence Berkeley National Laboratory.