Scientists at SLAC have found a new method to create coherent beams of twisted light – light that spirals around a central axis as it travels. It has the potential to generate twisted light in shorter pulses, higher intensities and a much wider range of wavelengths, including X-rays, than is currently possible.
Dao Xiang, a SLAC accelerator physicist, has received an international award for his work on a technique for tuning an electron beam with a laser to produce X-ray pulses with more uniform and predictable properties.
Crews will install a powerful new instrument, start assembling a new "self-seeding" system that will focus soft X-ray laser pulses into a bright, narrow band of colors, and upgrade several laser systems during two months of routine downtime at SLAC's Linac Coherent Light Source (LCLS) X-ray laser.
In a new state-of-the-art lab at SLAC National Accelerator Laboratory, components of ribosomes – tiny biological machines that make new proteins and play a vital role in gene expression and antibiotic treatments – form crystals in a liquid solution.
Signs at the lab's entryway warn of the potential for contamination – these delicate samples can be damaged by human touch, a sneeze or a dust particle.
A high-energy SLAC laser that creates shock waves and superhot plasmas needs to cool for about 10 minutes between shots. In the meantime, the rapid-fire pulses produced by SLAC's Linac Coherent Light Source X-ray laser, which probes the extreme states of matter produced by this initial laser shot, are unused.
It all comes down to one tiny spot on a diamond-cut, highly pure copper plate. That's where every X-ray laser pulse at SLAC's Linac Coherent Light Source gets its start. That tiny spot must be close to perfect or it can impair and even halt LCLS operations.
SLAC in May 2013 opened a new test facility at the Accelerator Structure Test Area (ASTA) to study the complex physics and chemistry that cause that shiny copper slab, called a cathode, to degrade over time, and to identify ways to maintain and improve its performance.