The world’s brightest X-ray machine has been turned on

The world’s brightest X-ray machine has produced record-breaking X-rays for the first time. This allows researchers to observe atoms, molecules, and chemical reactions in unparalleled detail.

A machine called the Linac Coherent Light Source II (LCLS-II) X-ray laser at California’s SLAC National Accelerator Laboratory recently completed an upgrade process that began more than a decade ago. The X-rays currently produced are on average 10,000 times brighter than the X-rays produced at his original LCLS facility.

LCLS-II produces X-rays through a complex process involving lasers, electrons, microwaves, and magnets. First, the researchers use an ultraviolet laser to knock the electrons out of a copper plate before accelerating them with a device that emits powerful microwave pulses. The electrons then move through a maze made up of thousands of magnets. This causes them to wiggle back and forth, emitting his X-rays in predictable and well-controlled bursts. Researchers shine these pulses on objects and materials to image their internal structures. X-rays are a trillion times brighter than those used in medical procedures.

The X-rays produced by LCLS-II have become so bright in part because the SLAC team retrofitted the three-kilometre-long metal tube through which the electrons pass with a niobium lining. This metal can withstand unprecedented exposure to high-energy electrons when cooled to about -271°C. To maintain Once the tubes were properly cooled, the team needed to install a huge cryogenic plant underground.

There were other engineering challenges as well. The maze magnet had to be calibrated very precisely to ensure that the X-ray pulses were of the correct shape. mike dunn At SLAC. “All parts of this system had to work properly at the same time.”

He and his colleagues began sending electrons through the niobium tunnel in September 2022. Over the past 12 months, they have calibrated every part of the machine and gradually increased its power.

“It’s been an incredible journey to see the invention and establishment of this new, disruptive, yet powerful technology for observing nature in action,” he says. Nadia Zatsepin At La Trobe University, Australia. “Initially, there were so many skeptics that this noisy and unstable machine, the first LCLS, would never produce new science. Now, more than a decade later, the use of these X-rays is well established. It is now well established that we can now observe in unprecedented detail how biochemical processes occur at the atomic scale.”

Zatsepin said LCLS-II will allow researchers to create “molecular movies” of biological processes such as mammalian vision, photosynthesis, drug binding, and gene regulation.

Dunn said the machine’s ability to produce not just bright X-rays but many X-rays in a very short period of time will allow researchers to produce technically important materials such as those used in artificial photosynthesizers and next-generation photosynthesizers. He says it will be possible to see what’s happening inside the material. semiconductor. And even more exotic materials, such as superconductors and so-called topological phases, which are not fully understood at the quantum level, may be unraveled by studying them with LCLS-II’s X-rays, he says. To tell.

“This is a very broad scientific tool, like a powerful microscope that can look at everything from quantum materials to biological systems to catalytic chemistry to nuclear physics; all of that and much more. “We’re going to do that,” Dunn said.