Using the Linac Coherent Light Source (LCLS) facility at the SLAC National Accelerator Laboratory, Lawrence Livermore scientists probed nitrogen gas at X-ray energies of up to 8 keV (kiloelectronvolts), the highest X-ray energy ever used at an XFEL, to see how it behaved when the laser hit it.
The photoluminescence-based pulse-energy detector allowed the team to study the interaction - including electron dynamics and space charge effects - between nitrogen gas and the XFEL beam. Understanding the precise dynamics at work on these scales will forever change the understanding of chemistry, physics and materials science.
The XFEL's light is so bright at 8 kilo electron volts and so fast (it has a pulse length from 10 femtoseconds to 100 femtoseconds) that LLNL scientists were able to validate the physics of simulations done using nitrogen gas. (One femtosecond is one quadrillionth of a second).
"The detailed physics is very important for most LCLS experiments since it determines the interpretation of the results," said Lab scientist Stefan Hau-Riege. "The unique thing about this experiment is that it was performed upstream from the LCLS mirrors, and so we had access to the full range of LCLS X-ray energies (which went up to 8 keV at the time)."
The heart of the LCLS is a free-electron laser that produces beams of coherent, high-energy X-rays. Coherence - the phenomenon of all photons in a beam acting together in perfect lockstep - makes laser light far brighter than ordinary light. Since X-ray photons at the LCLS are coherent, the resulting beam of light will be as much as a billion times brighter than any other X-ray light source available today.
The LCLS also contains a femto-camera that can sequence together images of the ultra small, taken with the ultrafast pulses of the LCLS. Scientists are for the first time creating molecular movies, revealing the frenetic action of the atomic world.
The LCLS, and its cousins planned in Germany and Japan, improves on third-generation light sources. The third-generation sources are circular, stadium-size synchrotrons, and they produce streams of incoherent X-ray photons. Since their pulses are long compared to the motion of electrons around an atom, synchrotron light sources cannot begin to explore the dynamic motion of molecules.
The pulses of light from the fourth-generation LCLS are so short, lasting for just quadrillionths of a second, that its beam provides an X-ray strobe light to capture such atomic and molecular behavior.
Other Livermore researchers include Richard Bionta, Dmitri Ryutov, Richard London, Elden Ables, Keith Kishiyama, Stewart Shen, Mark McKernan and Donn McMahon. Collaborators included the SLAC National Accelerator Laboratory and the Center for Free-Electron Laser Science, DESY, in Hamburg.
The research will appear in the July 27 online edition of Physical Review Letters.
Founded in 1952, Lawrence Livermore National Laboratory (www.llnl.gov) is a national security laboratory that develops science and engineering technology and provides innovative solutions to our nation's most important challenges. Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy's National Nuclear Security Administration.
Laboratory news releases and photos are also available at https://publicaffairs.llnl.gov/news/releases.html
Anne Stark | EurekAlert!
From rocks in Colorado, evidence of a 'chaotic solar system'
23.02.2017 | University of Wisconsin-Madison
Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
24.02.2017 | Life Sciences
24.02.2017 | Life Sciences
24.02.2017 | Trade Fair News