In order to improve the quality of the electron beam, the laser heater rocked back and forth along the path of the infrared laser beam. By hollowing out the beam, the team found that they could produce higher quality and more stable beams.
New research shows that when a beam of electrons is amplified in the middle of a ring laser beam, the beam of electrons can be wound with a higher quality and produce a brighter X-ray beam.
A group of scientists proposed a way to improve the electron beam and produce a brighter X-ray beam: put a ring on it. The team included researchers from the Department of Energy ’s SLAC National Accelerator Laboratory and Stanford University, and published their findings in the Physics Review Letter earlier this month.
On SLAC's linear accelerator coherent light source (LCLS) and other X-ray free electron lasers, scientists compress and accelerate the electron beam to near the speed of light, and then swing them back and forth through a series of magnets to generate X-rays. These X-rays are then used to study biological, chemical and material samples, enabling scientists to create high-resolution images of how their molecular structures move.
The researchers found that when these electron beams are long and smooth (such as American football), they are the most stable, can produce brighter X-rays with more uniform wavelengths, and can provide higher resolution images. But because SLAC scientist and principal researcher Sergio Carbajo says that because electrons repel each other when they are created in a vacuum, the beam will eventually become shorter and unpredictable, like "deflate" Football is covered by spikes. "
"Football Expansion"
To solve this problem, scientists used a device called a laser heater, a technology that has been long-term researched by co-authors Huang Zhirong Huang and Daniel Ratner on SLAC. The laser heater shakes the electron beam back and forth along the path of the infrared laser beam, allowing scientists to make longer and better shaped beams. Carbajo said that this process injects energy into the beam, "introduce some chaos as early as possible to prevent the production line from further chaos."
He said: "Our idea is that if we do nothing to swell and smooth the spikes of the football, and then send it to the linear accelerator, the imperfections will be amplified and the beam quality will deteriorate," He says. "However, if we 'heat' the electron and change its energy distribution at the beginning, we can customize its shape to improve its mass when it reaches the end of the accelerator."
"Donut Laser"
In this new study, the research team improved the device by hollowing out the laser beam into a ring-shaped "doughnut laser." This new electron shaping technology can improve the unevenness and produce a more stable beam, because it will shake the electrons differently according to how close the electrons are to the center of the ring. The end result is a perfectly shaped football suitable for flying in any subatomic Super Bowl.
"This technology improves the overall quality of the electron beam," Carbajo said. "It provides precise control of the shape of the electron beam, so it has groundbreaking significance in amplifying the performance of scientific instruments that rely on the electron beam (such as storage rings, linear accelerators and light sources).