SlacNationalAcceleratorLaboratory
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X-ray laser spots photosynthesis in real-life conditions
Humanity has known about the life-giving photosynthesis process for a long time, but studying it in real-world conditions has often been impractical. You've typically had to freeze samples to get a good look, which isn't exactly natural. However, the SLAC National Accelerator Laboratory just managed a breakthrough: it used its x-ray laser to capture detailed snapshots of photosynthesis at room temperature. The trick was to place protein complex samples in a solution, put that on a conveyor belt, light it up with a green laser (to start the water-splitting reaction) and capture images using x-ray pulses. As those pulses are extremely fast -- just 40 femtoseconds long -- you can collect crystallization and spectroscopy data before the sample meets its untimely end.
Scientists catch a classic quantum experiment on camera
If you know a bit about quantum physics, you've likely heard of the Schrödinger's Cat concept used to explain superpositions: a cat in a box with a poison flask is at once alive and dead until you look inside. Researchers have produced this oddball state in the lab before, but they're now using it to create the most detailed X-ray movies of molecules they've seen so far. A team at the SLAC National Accelerator Laboratory first blasted an iodine molecule with an optical laser, splitting the molecule into simultaneous excited and relaxed states. When the scientists hit the molecule with X-rays afterward, the light scattering off of both states created an X-ray hologram showing the excited state. After that, the SLAC group only had to capture enough of these holograms to create a movie.
World's most powerful X-ray laser will get 10,000 times brighter
If you think that Stanford's use of an super-bright X-ray laser to study the atom-level world is impressive, you're in for a treat. The school and its partners have started work on an upgrade, LCLS-II (Linac Coherent Light Source II), whose second laser beam will typically be 10,000 times brighter and 8,000 times faster than the first -- up to a million pulses per second. The feat will require an extremely cold (-456F), niobium-based superconducting accelerator cavity that conducts electricity with zero losses. In contrast, the original laser shoots through room-temperature copper at a relatively pedestrian 120 pulses per second.
Stanford's latest particle accelerator is smaller than a grain of rice (video)
Particle accelerators range in size from massive to compact, but researchers from Stanford University and the SLAC National Accelerator Laboratory have created one that's downright miniscule. What you see above is a specially patterned glass chip that's smaller than a grain of rice, but unlike a broken Coke bottle, it's capable of accelerating electrons at a rate that's roughly 10 times greater than the SLAC linear accelerator. Taken to its full potential, researchers envision the ability to match the accelerating power of the 2-mile long SLAC linear accelerator with a system that spans just 100 feet. For a rough understanding of how this chip works, imagine electrons that are brought up to near-light speed and then concentrated into a tiny channel within the glass chip that measures just a half-micron tall. From there, infrared laser light interacts with patterned, nanoscale ridges within the channel to create an electrical field that boosts the energy of the electrons. In the initial demonstration, researchers were able to create an energy increase of 300 million electronvolts per meter, but their ultimate goal is to more than triple that. Curiously enough, these numbers aren't even that crazy. For example, researchers at the University of Texas at Austin were able to accelerate electrons to 2 billion electronvolts over an inch with a technique known as laser-plasma acceleration, which involves firing a laser into a puff of gas. Even if Stanford's chip-based approach doesn't carry the same shock and awe, it seems the researchers are banking on its ability to scale over greater distances. Now if we can just talk them into strapping those lasers onto a few sharks, we'll really be in business.
Diamond hones DOE X-ray laser howitzer to razor-sharp precision
The US Department of Energy's SLAC accelerator lab already has a pretty useful X-ray laser -- the Linac Coherent Light Source (LCLS). But, recent modifications to the device have scientists drooling over its new found potential. Using a thin wafer of diamond, the Stanford-run lab filtered the beam to a lone frequency, then amplified it in a process called "self-seeding." That's given the world's most powerful X-ray laser even more punch by tossing out unneeded wavelengths which were reducing its intensity. The tweaks allow scientists across many fields to finesse and image matter at the atomic level, giving them more power to study and change it. According to the lab, researchers who came to observe the experiment from other X-ray laser facilities "were grinning from ear to ear" at the possibility of integrating the tech into their own labs. The SLAC team claims they could still add 10 times more punch to the LCLS with further optimization, putting the laser in a class by itself -- X-ray-wise, anyway.
X-ray laser bakes solid plasma from aluminum foil, brings us closer to nuclear fusion
Nuclear fusion, like flying cars, is one of those transparent, dangling carrots that've been stymying the scientific community and tickling our collective noses for decades. But recent research out of the Department of Energy's SLAC National Accelerator Laboratory might help us inch a few baby steps closer to that Jetsonian future. The experiment, conducted by a group of Oxford University scientists, utilized the DOE's Linac Coherent Light Source -- an X-ray laser capable of pulsing "more than a billion times brighter" than current synchrotron sources -- to transmute a piece of aluminum foil heated to 3.6 million degrees Fahrenheit (or 2 million degrees Celsius) into a cube of solid plasma. So, why go to such lengths to fry a tiny piece of metal at that extreme temperature? Simple: to replicate conditions found within stars and planets. Alright, so it's not that easy and we're still a ways off from actually duping celestial bodies, but the findings could help advance theories in the field and eventually unlock the powers of the Sun. Until that fateful day arrives, however, we'll just have to let these pedigreed pyros continue to play with their high-tech toys.
