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  • richardmitnick 3:41 pm on April 26, 2016 Permalink | Reply
    Tags: , , X-ray Technology   

    From LBL: “Seeing Atoms and Molecules in Action with an Electron ‘Eye’ “ 

    Berkeley Logo

    Berkeley Lab

    April 26, 2016
    Glenn Roberts Jr.
    510-486-5582
    geroberts@lbl.gov

    1
    Daniele Filippetto, a Berkeley Lab scientist, works on the High-Repetition-rate Electron Scattering apparatus (HiRES), which will function like an ultrafast electron camera. HiRES is a new capability that builds on the Advanced Photo-injector Experiment (APEX), a prototype electron source for advanced X-ray lasers. (Roy Kaltschmidt/Berkeley Lab)

    A unique rapid-fire electron source—originally built as a prototype for driving next-generation X-ray lasers—will help scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) study ultrafast chemical processes and changes in materials at the atomic scale. This could provide new insight in how to make materials with custom, controllable properties and improve the efficiency and output of chemical reactions.

    This newly launched setup, dubbed HiRES (for High Repetition-rate Electron Scattering apparatus), will function like an ultrafast electron camera, potentially producing images that can pinpoint defects and their effects, track electronic and superconducting properties in exotic materials, and detail chemical reactions in gases, liquids and biological samples that are difficult to study using more conventional, X-ray-based experiments.

    The new research tool produces highly focused electron bunches, each containing up to 1 million electrons. The electrons stream at a rate of up to 1 million bunches per second, or 1 trillion electrons per second.

    Electrons will be used as a fast camera shutter to capture snapshots of samples as they change over femtoseconds, or quadrillionths of a second. An initial laser pulse will trigger a reaction in the sample that is followed an instant later by an electron pulse to produce an image of that reaction.

    HiRES delivered its first electron beam March 28 and experiments are set to begin in May.

    Daniele Filippetto, a Berkeley Lab scientist who is leading HiRES, has for much of his scientific career focused on building electron sources, also called “electron guns,” that can drive advanced X-ray lasers known as “free-electron lasers.” These electron guns are designed to produce a chain of high-energy electron pulses that are accelerated and then forced by powerful magnetic fields to give up some of their energy in the form of X-ray light.

    SACLA Free-Electron Laser Riken Japan
    SACLA Free-Electron Laser Riken Japan

    Free-electron lasers have opened new frontiers in studying materials and chemistry at the nanoscale and beyond, and Filippetto said he hopes to pave new ground with HiRES, too, using a technique known as “ultrafast electron diffraction,” or UED, that is similar to X-ray diffraction.

    In these techniques, a beam of X-rays or electrons hits a sample, and the scattering of X-rays or electrons is collected on a detector. This pattern, known as a diffraction pattern, provides structural information about the sample. X-rays and electrons interact differently: electrons scatter from a sample’s electrons and the atoms’ nuclei, for example, while X-rays scatter only from the electrons.

    The unique electron gun that Filippetto and his team are using is a part of Berkeley Lab’s APEX (Advanced Photo-injector EXperiment), which has served as a prototype system for LCLS-II, a next-generation X-ray laser project underway at SLAC National Acceleratory Laboratory in Menlo Park, Calif. Berkeley Lab is a member of the LCLS-II project collaboration.

    “The APEX gun is a unique source of ultrafast electrons, with the potential to reach unprecedented precision and stability in timing—ultimately at or below 10 femtoseconds,” Filippetto said. “With HiRES, the time resolution will be about 100 femtoseconds, or the time it takes for chemical bonds to form and break. So you can look at the same kinds of processes that you can look at with an X-ray free-electron laser, but with an electron eye.”

    He added, “You can see the structure and the relative distances between atoms in a molecule changing over time across the whole structure. You need fewer electrons than X-rays to get an image, and in principal there can be much less damage to the sample with electrons.”

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    This computerized rendering shows the layout of the HiRES ultrafast electron diffraction beamline, which is located in the domed Advanced Light Source building at Berkeley Lab. At left (on blue base) is APEX, the electron source for HiRES. (Courtesy of Daniele Filippetto/Berkeley Lab)

    Filippetto in 2014 received a five-year DOE Early Career Research Program award that is supporting his work on HiRES. The work is also supported by the Berkeley Lab Laboratory Directed Research and Development Program.

    Already, Berkeley Lab has world-class research capabilities in other electron-beam microscopic imaging techniques, in building nanostructures, and in a range of X-ray experimental techniques, Filippetto noted. All of these capabilities are accessible to the world’s scientists via the lab’s Molecular Foundry and Advanced Light Source (ALS).

    “If we couple all of these together with the power of HiRES, then you basically can collect full information from your samples,” he said. “You can get static images with subatomic resolution, the ultrafast structural response, and chemical information about a sample—in the same lab and in the same week.”

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    A view of the HiRES ultrafast electron diffraction (UED) beamline at Berkeley Lab’s APEX. (Roy Kaltschmidt/Berkeley Lab)

    Filippetto has a goal to improve the focus of the HiRES electron beam from microns, or millionths of a meter in diameter, to the nanometer scale (billionths of a meter), and to also improve the timing from hundredths of femtoseconds to tens of femtoseconds to boost the quality of the images it produces and also to study even faster processes at the atomic scale.

    Andrew Minor, director of the Molecular Foundry’s National Center for Electron Microscopy said he is excited about the potential for HiRES to ultimately study the structure of single molecules and to explore the propagation of microscopic defects in materials at the speed of sound.

    “We want to study nanoscale processes such as the structural changes in a material as a crack moves through it at the speed of sound,” he said. Also, the timing of HiRES may allow scientists to study real-time chemical reactions in an operating battery, he added.

    “What is really interesting to me is that you can potentially focus the beam down to a small size, and then you would really have a system that competes with X-ray free-electron lasers,” Minor said, which opens up the possibility of electron imaging of single biological particles.

    He added, “I think there is a very large unexplored space in terms of using electrons at the picosecond (trillionths of a second) and nanosecond (billionths off a second) time scales to directly image materials.”

    There are tradeoffs in using X-rays vs. electrons to study ultrafast processes at ultrasmall scales, he noted, though “even if the capabilities are similar, it’s worth pursuing” because of the smaller size and lesser cost of machines like APEX and HiRES compared to X-ray free-electron lasers.

    Scientists from Berkeley Lab’s Materials Sciences Division and from UC Berkeley will conduct the first set of experiments using HiRES, Filippetto said, including studies of the structural and electronic properties of single-layer and multilayer graphene, as well as other materials with semiconductor and superconductor properties.

    There are also some clear uses for HiRES in chemistry and biology experiments, Filippetto noted. “The idea is to push things to see ever-more-complicated structures and to open the doors to all of the possible applications,” he said.

    There are plans to forge connections between HiRES and other lab facilities, like the ALS, where HiRES is located, and the lab’s National Center for Electron Microscopy at the Molecular Foundry.

    “Already, we are working with the microscopy center on the first experiments,” Filippetto added. “We are adapting the microscope’s sample holder so that one can easily move samples from one instrument to another.”

    Filippetto said there are discussions with ALS scientists on the possibility of gathering complementary information from the same samples using both X-rays from the ALS and electrons from HiRES.

    “This would make HiRES more accessible to a larger scientific community,” he added.

    The Molecular Foundry and Advanced Light Source are DOE Office of Science User Facilities. HiRES is supported by the U.S. Department of Energy Office of Science.

    LBL Advanced Light Source
    LBL Advanced Light Source

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    A labeled diagram showing the components of the HiRES beamline at Berkeley Lab. (Courtesy of Daniele Filippetto/Berkeley Lab)

    See the full article here .

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  • richardmitnick 11:39 am on April 18, 2016 Permalink | Reply
    Tags: , , , , X-ray Technology, XFEL   

    From LC: “From metal sheet to particle accelerator (Part 1of 3)” 

    Linear Collider Collaboration header
    Linear Collider Collaboration

    14 April 2016
    Ricarda Laasch

    1
    Cavity production at Zanon in Italy. Image: DESY, Heiner Müller-Elsner

    In September 2015, the 50th accelerator module for the X-ray free-electron laser European XFEL was tested at DESY. One hundred accelerator modules are needed for the two-kilometre-long electron accelerator of the X-ray free-electron laser. Each module consists of eight cavities, the actual accelerating structures. This is the first of a three-part series (first published in DESY inForm) about how these technological masterpieces are manufactured. Part 1 is about cavities; their production has now been completed.

    Two companies have been commissioned with the cavity production: Research Instruments (RI) in Germany and Zanon in Italy. “This is the first time we have ordered cavities virtually ready for operation from industry,” emphasises Axel Matheisen who together with Waldemar Singer leads a team of engineers and technicians at DESY supervising these firms. In the past, industry had only carried out the mechanical production steps. “For that reason, our greatest concern was whether we would manage to convey the necessary knowledge in a way that the companies are able to produce complete cavities,” says Mattheisen. The tested cavities prove that this knowledge transfer worked perfectly.

    At the beginning of the long production process, there is a square niobium sheet with an edge length of 26.5 centimetres and a thickness of 2.8 millimetres. For the construction of the accelerator, the purity of 14 700 sheets is tested at DESY before being dispatched to the two production firms. There, the sheets are deep-drawn to so-called half cells which gives them the appropriate shape for further processing. A stamp is used to obtain the required hollow pattern … the cavity.

    Subsequently, 18 half cells are welded together to form one cavity. Since niobium oxidises very easily, this cannot be done with a flame. Instead, the half cells are welded together with an electron beam in a vacuum chamber. The advantage: this procedure is very clean. For this reason, the nine-cell cavity must be protected from new contamination during further processing.

    For accelerator operation, the quality of the cavity’s inner surface is extremely important. It must not only be hyper clean but also exceptionally smooth. “In the past, the cavities were delivered to us and we did the rest. This went quite well with ten or occasionally with 30 cavities per year. But it was clear that this would not be possible with some 100 cavities per year,” Mattheisen says. For the construction of the European XFEL, the firms had to learn to carry out the surface treatment according to the “DESY recipe” and to work in a nearly dust-free cleanroom. “This was completely new for them and therefore, communication was ex- tremely important,” Mattheisen points out. The most important steps in this process are pickling, baking, tuning, dressing and rinsing.

    For pickling, various different acid mixtures are lled into the cavity. The acid reacts with the metal surface of the cavity and removes processing residues and polishes the surface. The acids’ mixture ratio and the extent of the pickling procedure have been optimised during many years of research at DESY. Baking follows pickling: the cavity is heated at 800 degrees centigrade for several hours in a humidity-free vacuum environment. During this treatment, tensions in the metal originating from shaping and welding are released and the ne crystal structures of niobium are newly arranged.

    After getting out of the oven, the cavity is tuned. In order to accelerate particles during operation, electromagnetic fields are induced to oscillate in the cavity and, eventually, the oscillation will turn into resonance. For this aim, however, the shape of each cavity cell must be exactly tuned to the accelerator frequency of 1.3 gigahertz. In the process of tuning, the resonance frequency is measured and when it diverges from the desired frequency, the cavity must be retuned. For this purpose, the cavity shells are pressed and pushed accordingly. Slight shape alterations can signi cantly improve the resonance.

    The next step is dressing: the cavity is welded into its helium tank. Liquid helium cools down the cavity in operation to minus 271 degrees centigrade to generate superconductivity and remove heat. Subsequently, a total of four antennae are to be mounted onto the cavity. One of it feeds the electromagnetic field into the cavity, the others recover it at the opposite end. “Doing this kind of mounting in a cleanroom is not the average, not even for industry,” says Mattheisen. “It is not usual work to set bolts and nuts in a cleanroom; it requires practice and, above all, patience since all procedures must be carried out slowly.”

    The production is completed with rinsing: the inner surface of the cavity is sprayed off for some hours with high pressure ultrapure water of 100 bar. Now, the cavity with a vacuum inside leaves the cleanroom. Packed in a special case, it is shipped to DESY by lorry. However, the cavity is not yet ready for installation into a European XFEL module. It will first have to demonstrate its qualities.

    See the full article here .

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    The Linear Collider Collaboration is an organisation that brings the two most likely candidates, the Compact Linear Collider Study (CLIC) and the International Liner Collider (ILC), together under one roof. Headed by former LHC Project Manager Lyn Evans, it strives to coordinate the research and development work that is being done for accelerators and detectors around the world and to take the project linear collider to the next step: a decision that it will be built, and where.

    Some 2000 scientists – particle physicists, accelerator physicists, engineers – are involved in the ILC or in CLIC, and often in both projects. They work on state-of-the-art detector technologies, new acceleration techniques, the civil engineering aspect of building a straight tunnel of at least 30 kilometres in length, a reliable cost estimate and many more aspects that projects of this scale require. The Linear Collider Collaboration ensures that synergies between the two friendly competitors are used to the maximum.

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  • richardmitnick 9:16 am on April 14, 2016 Permalink | Reply
    Tags: , , X-ray Technology   

    From DESY: “First user operation at FLASH2” 

    DESY
    DESY

    1
    FLASH is the first X-ray laser worldwide which can serve experiments at two beamlines at the same time

    DESY/FLASH
    DESY/FLASH

    Since Friday, 8 April at 12:14 h FLASH is running in parallel operation for two user experiments, one in the experimental hall “Albert Einstein” (FLASH1) and one in the new hall “Kai Siegbahn” (FLASH2). First official FLASH2 users are the researchers around Sven Toleikis and Andreas Przystawik at beamline FL24 who focus the FLASH2 pulses with the help of a multilayer mirror onto rare gas clusters and study the fluorescence of the resulting nanoplasma as a function of cluster size.

    Right after the successful start last Friday the first record for this doubled user operation was set: On Saturday, FLASH delivered 4000 pulses per second with up to 140 micro joule (µJ) per pulse to an experiment of Mark Dean et al. (Brookhaven National Laboratory, New York) at FLASH1 beamline PG1 and in parallel 110 pulses per second with about 100 micro joule each for FLASH2 making it a successful start at both ends.

    The second free-electron laser line, FLASH2, has been realized from 2011 to 2015. Soon after the first successful generation of extremely intense FEL radiation on FLASH2 in August 2014, parallel operation of the two soft X-ray free-electron lasers, FLASH1 and FLASH2, has been established. Now, the first FEL beamline in the new hall “Kai Siegbahn” is operational making it possible to run two experiments simultaneously on FLASH1 and FLASH2, both delivering intense, ultra-short laser pulses with user-specific parameters.

    2
    Click me! First user experiment at FLASH2: fluorescence of Xe clusters excited by the FLASH2 pulses. Left: Nozzle where the clusters exit. Middle: fluorescence in the focus of the multilayer mirror (higher intensity left and right of the centre, since there are more clusters which fluoresce). Right (weaker ‘circles’): fluorescence of the clusters in the incoming unfocused FEL beam.

    See the full article here .

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    DESY is one of the world’s leading accelerator centres. Researchers use the large-scale facilities at DESY to explore the microcosm in all its variety – from the interactions of tiny elementary particles and the behaviour of new types of nanomaterials to biomolecular processes that are essential to life. The accelerators and detectors that DESY develops and builds are unique research tools. The facilities generate the world’s most intense X-ray light, accelerate particles to record energies and open completely new windows onto the universe. 
That makes DESY not only a magnet for more than 3000 guest researchers from over 40 countries every year, but also a coveted partner for national and international cooperations. Committed young researchers find an exciting interdisciplinary setting at DESY. The research centre offers specialized training for a large number of professions. DESY cooperates with industry and business to promote new technologies that will benefit society and encourage innovations. This also benefits the metropolitan regions of the two DESY locations, Hamburg and Zeuthen near Berlin.

     
  • richardmitnick 12:58 pm on April 4, 2016 Permalink | Reply
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    From SLAC: “Major Upgrade Will Boost Power of World’s Brightest X-ray Laser” 


    SLAC Lab

    April 4, 2016

    Construction begins today on a major upgrade to a unique X-ray laser at the Department of Energy’s SLAC National Accelerator Laboratory. The project will add a second X-ray laser beam that’s 10,000 times brighter, on average, than the first one and fires 8,000 times faster, up to a million pulses per second.

    The project, known as LCLS-II, will greatly increase the power and capacity of SLAC’s Linac Coherent Light Source (LCLS) for experiments that sharpen our view of how nature works on the atomic level and on ultrafast timescales.

    SLAC/LCLS
    SLAC/LCLS

    “LCLS-II will take X-ray science to the next level, opening the door to a whole new range of studies of the ultrafast and ultrasmall,” said LCLS Director Mike Dunne.

    SLAC/LCLS II schematic
    SLAC/LCLS II schematic

    “This will tremendously advance our ability to develop transformative technologies of the future, including novel electronics, life-saving drugs and innovative energy solutions.”

    SLAC Director Chi-Chang Kao said, “Our lab has a long tradition of building and operating premier X-ray sources that help users from around the world pursue cutting-edge research in chemistry, materials science, biology and energy research. LCLS-II will keep the U.S. at the forefront of X-ray science.”


    Access mp4 video here .
    This movie introduces LCLS-II, a future light source at SLAC. It will generate over 8,000 times more light pulses per second than today’s most powerful X-ray laser, LCLS, and produce an almost continuous X-ray beam that on average will be 10,000 times brighter. These unrivaled capabilities will help researchers address a number of grand challenges in science by capturing detailed snapshots of rapid processes that are beyond the reach of other light sources. (SLAC National Accelerator Laboratory)

    A Superior X-ray Microscope

    When LCLS opened six years ago as a DOE Office of Science User Facility, it was the first light source of its kind – a unique X-ray microscope that uses the brightest and fastest X-ray pulses ever made to provide unprecedented details of the atomic world.

    Hundreds of scientists use LCLS each year to catch a glimpse of nature’s fundamental processes in unprecedented detail. Molecular movies reveal how chemical bonds form and break; ultrafast snapshots capture electric charges as they rapidly rearrange in materials and change their properties; and sharp 3-D images of disease-related proteins provide atomic-level details that could hold the key for discovering potential cures.

    The new X-ray laser will work in parallel with the existing one, with each occupying one-third of SLAC’s 2-mile-long linear accelerator tunnel. Together they will allow researchers to make observations over a wider energy range, capture detailed snapshots of rapid processes, probe delicate samples that are beyond the reach of other light sources and gather more data in less time, thus greatly increasing the number of experiments that can be performed at this pioneering facility.

    “The upgrade will benefit X-ray experiments in many different ways, and I’m very excited to use the new capabilities for my own research,” said Brown University Professor Peter Weber, who co-led an LCLS study that used X-ray scattering to track ultrafast structural changes as ring-shaped gas molecules burst open in a chemical reaction vital to many processes in nature. “With LCLS-II, we’ll be able to bring the motions of atoms much more into focus, which will help us better understand the dynamics of crucial chemical reactions.”

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    The future LCLS-II X-ray laser (blue, at left) is shown alongside the existing LCLS (red, at right). LCLS uses the last third of SLAC’s 2-mile-long linear accelerator – a hollow copper structure that operates at room temperature and allows the generation of 120 X-ray pulses per second. For LCLS-II, the first third of the copper accelerator will be replaced with a superconducting one, capable of creating up to 1 million X-ray flashes per second. (SLAC National Accelerator Laboratory)

    A Big Leap in X-ray Laser Performance

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    This photo shows the prototype of a novel electron source for LCLS-II. Located at the future X-ray laser’s front end, it will produce bunches of electrons for the generation of X-ray pulses that are only quadrillionths of a second long, at rates of up to a million bunches per second. (R. Kaltschmidt/Berkeley Lab)

    Like the existing facility, LCLS-II will use electrons accelerated to nearly the speed of light to generate beams of extremely bright X-ray laser light. The electrons fly through a series of magnets, called an undulator, that forces them to travel a zigzag path and give off energy in the form of X-rays.

    But the way those electrons are accelerated will be quite different, and give LCLS-II much different capabilities.

    At present, electrons are accelerated down a copper pipe that operates at room temperature and allows the generation of 120 X-ray laser pulses per second.

    For LCLS-II, crews will install a superconducting accelerator. It’s called “superconducting” because its niobium metal cavities conduct electricity with nearly zero loss when chilled to minus 456 degrees Fahrenheit. Accelerating electrons through a series of these cavities allows the generation of an almost continuous X-ray laser beam with pulses that are 10,000 times brighter, on average, than those of LCLS and arrive up to a million times per second.

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    Electron bunches will gain energy in niobium cavities like these. Cooled to extremely low temperature, these “superconducting” cavities allow radiofrequency fields to boost electron energies without electrical resistance – a crucial property for the acceleration of electrons at a rate of up to a million bunches per second. (R. Hahn/Fermilab)

    In addition to a new accelerator, LCLS-II requires a number of other cutting-edge components, including a new electron source, two powerful cryoplants that produce refrigerant for the niobium structures, and two new undulators to generate X-rays.

    4
    This image shows a segment of an undulator magnet that will turn powerful beams of electrons into extremely bright X-ray light. Two undulators for generating low- and high-energy X-rays at SLAC’s future X-ray laser facility will consist of 21 and 32 segments, respectively. (R. Kaltschmidt/Berkeley Lab)

    6
    Illustration of the electron accelerator of SLAC’s future rapid-fire LCLS-II X-ray laser. No image credit

    Strong Partnerships for a Bright Future in X-ray Science

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    For LCLS-II, SLAC has teamed up with four other national labs – Argonne, Berkeley Lab, Fermilab and Jefferson Lab – and Cornell University, with each partner making key contributions to the many aspects of project planning as well as component design, acquisition and construction. (SLAC National Accelerator Laboratory)

    To make this major upgrade a reality, SLAC has teamed up with four other national labs – Argonne, Berkeley Lab, Fermilab and Jefferson Lab – and Cornell University, with each partner making key contributions to project planning as well as to component design, acquisition and construction.

    “We couldn’t do this without our collaborators,” said SLAC’s John Galayda, head of the LCLS-II project team. “To bring all the components together and succeed, we need the expertise of all partners, their key infrastructure and the commitment of their best people.”

    With favorable “Critical Decisions 2 and 3 (CD-2/3)” in March, DOE has formally approved construction of the $1 billion project, which is being funded by DOE’s Office of Science. SLAC is now clearing out the first third of the linac to make room for the superconducting accelerator, which is scheduled to begin operations in the early 2020s. In the meantime, LCLS will continue to serve the X-ray science community, except for a construction-related, six-month downtime in 2017 and a 12-month shutdown extending from 2018 into 2019.

    With the upgrades that are now moving forward, Dunne said, SLAC will have an X-ray laser facility that will enable groundbreaking research for years to come.

    See the full article here .

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    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.
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  • richardmitnick 9:23 pm on March 9, 2016 Permalink | Reply
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    From SLAC: “5 Ways SLAC’s X-ray Laser Can Change the Way We Live” 


    SLAC Lab

    March 9, 2016

    The First Five Years’ Points to a Bright Future of High-impact Discovery at LCLS

    SLAC LCLS
    LCLS

    SLAC LCLS-II line
    LCLS II

    If you’ve ever stood in a dark room wishing you had a flashlight, then you understand how scientists feel when faced with the mysteries of physical processes that happen at scales that are mind-bogglingly small and fast.

    The future of life-changing science – science that will spawn the electronic devices, medications and energy solutions of the future – depends on being able to see atoms and molecules at work.

    To do that you need special light – such as X-ray light with a wavelength as small as an atom – that pulses at the rate of femtoseconds. A femtosecond is to a second what a second is to 32 million years. It is the timescale for the basic building blocks of chemistry, biology and materials science.

    That’s why, six years ago, the Department of Energy’s SLAC National Accelerator Laboratory answered a bold call by the scientific community: Build a transformative tool for discovery, an X-ray laser so bright and fast it can unravel the hidden dynamics of our physical world.

    Since it began operation in 2009, this singularly powerful “microscope” has generated molecular movies, gotten a glimpse of the birth of a chemical bond, traced electrons moving through materials and made 3-D pictures of proteins that are key to drug discovery. Known to scientists as an X-ray free-electron laser (XFEL), SLAC’s Linac Coherent Light Source, or LCLS, is a DOE Office of Science User Facility that draws many hundreds of scientists from around the world each year to perform innovative experiments.

    The success of LCLS has inspired the spread of such machines all over the world.

    The latest issue of Reviews of Modern Physics contains the most comprehensive scientific overview of its accomplishments in a paper entitled, Linac Coherent Light Source: The First Five Years.

    LCLS staff scientists devoted about a year to compiling the collection of reports, says LCLS Director Mike Dunne.

    “We hope this extensive paper will be a valuable go-to source for this new field of science,” he said. “It describes many of the major accomplishments of the first X-ray laser of its kind. It also testifies to the power of this unique tool for scientific discovery that will benefit society in many ways.”

    Here are five ways SLAC’s X-ray laser and the science it enables can impact our future.

    1. Next-generation Computers and the Power Grid

    LCLS studies are helping to home in on the most promising materials and methods for transforming the electric power grid and driving next-generation computer components beyond classical limits.

    To make computers and other electronics faster and smaller, scientists need to understand and control materials’ magnetism and electronic behavior in new and more precise ways.

    LCLS has given us new, nanoscale views of how laser light rapidly flips the magnetic state of materials, providing new insight on how to write data with light. It has pinpointed the speed of electrical switching – such as what occurs in semiconductor transistors – with trillionth-of-a-second precision.

    Researchers at LCLS have also discovered a new, 3-D phenomenon that may be linked to high-temperature superconductivity, which allows some exotic materials to conduct electricity with zero resistance.

    2. Better, Cleaner Fuels and Chemicals

    The ability to take direct measurements of never-before-seen steps in chemical reactions is what scientists need to design more efficient reactions to produce fuels, fertilizers and industrial chemicals.

    While we know the starting ingredients and outcomes of chemical reactions, the early and middle steps are hard to see in real time at the atomic scale.

    LCLS X-ray pulses are so fast that they allow us to observe and analyze these previously unseen steps. They work like ultrabright flashes to capture X-ray snapshots of chemical reactions as they happen.

    Researchers have used LCLS to see new details of a reaction in catalytic converters that neutralizes pollution from car exhaust, and to produce “molecular movies” of a molecule transforming after one of its chemical bonds breaks.

    3. More Effective Medication with Fewer Side Effects

    Half of the medications on the market target special receptor proteins in the outer layer of our cells. To figure out how drugs work so we can make them more effective and reduce side effects, we need to see how they dock with these receptors in atom-by-atom detail.

    The best way to see how they fit is to form the protein-drug complexes into crystals and study them with X-rays, but many important samples don’t form big enough crystals or are too damage-prone for conventional X-ray tools. LCLS, though, can study very tiny crystals under more natural conditions, making it possible to determine the 3-D atomic structure of important proteins that had been out of reach.

    Already, LCLS has revealed a potential weakness in a protein involved in the transmission of African sleeping sickness, provided the best 3-D atomic-scale look at how blood pressure medicines and painkillers interact with receptors in our cells, and pinpointed the mechanism that allows our brain to send ultrafast chemical signals.

    In more recent studies, LCLS has also been used to image living bacteria that are responsible for generating the oxygen in our atmosphere, demonstrating an entirely new X-ray imaging technique.

    4. Renewable Energy that Mimics Nature

    LCLS allows us to study how plants use energy from sunlight to release oxygen into the air we breathe during a process called photosynthesis. The X-ray laser is uniquely capable of mapping the individual sunlight-triggered steps. Early data is already giving us a detailed understanding of photosynthesis – information that’s crucial for developing renewable, clean sources of energy that mimic nature.

    Scientists are also using the tool to study how light affects other living things. Just as sunlight can be life-giving, it can also be damaging. Studies at LCLS have revealed how our DNA protects itself from the sun’s ultraviolet rays and how proteins in bacteria and in our eyes shift shape in response to light.

    5. Fusion Reactions and Seeing Inside Planets

    High-power laser systems at SLAC heat matter to millions of degrees and crush it with billions of tons of pressure per square inch. Scientists use LCLS to measure what happens to matter under these extreme conditions with high precision at very small scales, and over very short periods of time.

    Some studies test the resilience of materials, such as those used in jet engines, to see how they fail. Others have simulated and studied the shock effects of meteorite impacts and have reproduced the conditions that are believed to exist at the heart of giant gas planets, which improves our understanding of how solar systems form.

    The results also give scientists new insight into how to replicate the fusion reactions that fuel our sun, an essential step in the pursuit of fusion energy as a power source.
    Looking to the Future

    “Many of the methods developed over the first years of LCLS operations responded to the needs of science to address vital areas of discovery that promise to have a significant impact on our lives,” Dunne emphasizes. “We expect that the coming years of XFEL innovation will push us further into the future, as we look ever deeper into the dynamics of our natural world.”

    “The Linac Coherent Light Source: The First Five Years,” was authored by a team representative of the X-ray and accelerator science groups at SLAC during this pioneering period of XFEL science: Christoph Bostedt, Sébastien Boutet, David M. Fritz, Zhirong Huang, Hae Ja Lee, Henrik T. Lemke, Aymeric Robert, William F. Schlotter, Joshua J. Turner and Garth J. Williams.

    Citation: Bostedt, et al., Reviews of Modern Physics, 9 March 2016 (10.1103/RevModPhys.88.015007).

    See the full article here .

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    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.
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  • richardmitnick 1:01 pm on March 2, 2016 Permalink | Reply
    Tags: , , , X-ray Technology   

    From XFEL: “All segments of first light-generating system installed in European XFEL” 

    XFEL bloc

    European XFEL

    01 March 2016
    No writer credit

    Facility reaches prominent milestone

    In the metropolitan area of Hamburg, the installation of the 35 segments of the first of three X-ray light producing components of the European XFEL has been completed. Set into one of the facility’s tunnels, the segments are the core part of three systems called undulators, which are each up to 210 metres long and will produce X-ray laser light exceeding the intensity of conventional X-ray sources by a billion times.

    XFEL Undulator
    XFEL undulator. No image credit.

    These pulses of X-ray radiation are the basis for new revolutionary experimental techniques that will allow scientists to study the nanocosmos, with applications in many fields including biochemistry, astrophysics, and materials science. The undulator installation is a major step towards the completion of the European XFEL, a 3.4 km-long X-ray free-electron laser facility that will be the world’s brightest X-ray source when completed. It is also one of Europe’s largest research projects and is due to open to users for research in 2017.

    “With the 35 segments of the first undulator beam line in place, we have clearly reached a very important milestone in the construction of our facility”, says European XFEL Managing Director Prof. Massimo Altarelli. “The X-ray flashes produced in these systems are the basis for the future research at the European XFEL. We are looking forward to 2017, when they will be used to investigate the smallest details of the structure and function of matter in the molecular world.”

    Each of the 35 segments is 5 m long, weighs 7.5 t, and is composed of two girders facing one another, each holding a line of alternating strong permanent magnets. When accelerated electrons pass through the field of alternating polarity generated by the magnets, ultrashort flashes of X-ray laser light are produced. Components between adjacent segments help ensure a consistent magnetic field between them, and control systems allow mechanical movement of components within the undulator, which allows generation of a large spectrum of photon wavelengths.

    Design, development, and prototyping work started approximately eight years ago in a joint collaboration with DESY, European XFEL’s largest shareholder. The same technology is also used in a number of projects at DESY, including the X-ray free-electron laser FLASH and the PETRA III storage ring light source.

    DESY FLASH
    DESY FLASH

    DESY Petra III interior
    DESY PETRA III

    The undulator system was built through a multinational collaboration. The challenging production involved DESY and Russian, German, Swiss, Italian, Slovenian, Swedish, and Chinese institutes and companies under the leadership of the undulator group of the European XFEL. This includes a number in-kind contributions such as electromagnets for the electron beamline designed and manufactured at several institutes in Russia and tested in Sweden; temperature monitoring units from the Manne Siegbahn Laboratory in Sweden; and movers, phase shifters, and control systems designed and manufactured by the research centre CIEMAT in Spain.

    “This was a true synergetic collaboration”, says Joachim Pflüger, group leader of the European XFEL undulator group. “The resources and experience of DESY were essential for the development of the undulator systems. Now there is a great mutual benefit!”

    This first completed undulator will generate short-wavelength “hard” X-rays that will be used for experiments with a focus on structural biology and ultrafast chemistry. All three of the undulators planned for the starting phase of the European XFEL will be operational by the end of 2016.

    How the XFEL undulator works
    How the undulator works.

    See the full article here .

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    The Hamburg area will soon boast a research facility of superlatives: The European XFEL will generate ultrashort X-ray flashes—27 000 times per second and with a brilliance that is a billion times higher than that of the best conventional X-ray radiation sources.

    The outstanding characteristics of the facility are unique worldwide. Starting in 2017, it will open up completely new research opportunities for scientists and industrial users.

     
  • richardmitnick 2:07 pm on February 10, 2016 Permalink | Reply
    Tags: , Biomolecules, , , , X-ray Technology   

    From DESY: “New method opens crystal clear views of biomolecules” 

    DESY
    DESY

    2016/02/11
    No writer credit found

    A scientific breakthrough gives researchers access to the blueprint of thousands of molecules of great relevance to medicine and biology. The novel technique, pioneered by a team led by DESY scientist Professor Henry Chapman from the Center for Free-Electron Laser Science CFEL and reported this week in the scientific journal Nature, opens up an easy way to determine the spatial structures of proteins and other molecules, many of which are practically inaccessible by existing methods. The structures of biomolecules reveal their modes of action and give insights into the workings of the machinery of life. Obtaining the molecular structure of particular proteins, for example, can provide the basis for the development of tailor-made drugs against many diseases. “Our discovery will allow us to directly view large protein complexes in atomic detail,” says Chapman, who is also a professor at the University of Hamburg and a member of the Hamburg Centre for Ultrafast Imaging CUI.

    Dimer crystals Detec of complex biomolecules like that of the photosystem II molecule shown here
    Slightly disordered crystals of complex biomolecules like that of the photosystem II molecule shown here produce a complex continous diffraction pattern (right, the disorder is greatly exaggerated) under X-ray light that contains far more information than the so-called Bragg peaks of a strongly ordered crystal alone (left). Credit: DESY, Eberhard Reimann

    To determine the spatial structure of a biomolecule, scientists mainly rely on a technique called crystallography. The new work offers a direct route to “read” the atomic structure of complex biomolecules by crystallography without the usual need for prior knowledge and chemical insight. “This discovery has the potential to become a true revolution for the crystallography of complex matter,” says the chairman of DESY’s board of directors, Professor Helmut Dosch.

    In crystallography, the structure of a crystal and of its constituents can be investigated by shining X-rays on it. The X-rays scatter from the crystal in many different directions, producing an intricate and characteristic pattern of numerous bright spots, called Bragg peaks (named after the British crystallography pioneers William Henry and William Lawrence Bragg). The positions and strengths of these spots contain information about the structure of the crystal and of its constituents. Using this approach, researchers have already determined the atomic structures of tens of thousands of proteins and other biomolecules.

    But the method suffers from two significant barriers, which make structure determination extremely difficult or sometimes impossible. The first is that the molecules must be formed into very high quality crystals. Most biomolecules do not naturally form crystals. However, without the necessary perfect, regular arrangement of the molecules in the crystal, only a limited number of Bragg peaks are visible. This means the structure cannot be determined, or at best only a fuzzy “low resolution” facsimile of the molecule can be found. This barrier is most severe for large protein complexes such as membrane proteins. These systems participate in a range of biological processes and many are the targets of today’s drugs. Great skill and quite some luck are needed to obtain high-quality crystals of them.

    Extreme Sudoku in three dimensions

    The second barrier is that the structure of a complex molecule is still extremely difficult to determine, even when good diffraction is available. “This task is like extreme Sudoku in three dimensions and a million boxes, but with only half the necessary clues,” explains Chapman. In crystallography, this puzzle is referred to as the phase problem. Without knowing the phase – the lag of the crests of one diffracted wave to another – it is not possible to compute an image of the molecule from the measured diffraction pattern. But phases can’t be measured. To solve the tricky phase puzzle, more information must be known than just the measured Bragg peaks. This additional information can sometimes be obtained by X-raying crystals of chemically modified molecules, or by already knowing the structure of a closely-related molecule.

    When thinking about why protein crystals do not always “diffract”, Chapman realised that imperfect crystals and the phase problem are linked. The key lies in a weak “continuous” scattering that arises when crystals become disordered. Usually, this non-Bragg, continuous diffraction is thought of as a nuisance, although it can be useful for providing insights into vibrations and dynamics of molecules. But when the disorder consists only of displacements of the individual molecules from their ideal positions in the crystal then the “background” takes on a much more complex character – and its rich structure is anything but diffuse. It then offers a much bigger prize than the analysis of the Bragg peaks: the continuously-modulated “background” fully encodes the diffracted waves from individual “single” molecules.

    “If you would shoot X-rays on a single molecule, it would produce a continuous diffraction pattern free of any Bragg spots,” explains lead author Dr. Kartik Ayyer from Chapman’s CFEL group at DESY. “The pattern would be extremely weak, however, and very difficult to measure. But the ‘background’ in our crystal analysis is like accumulating many shots from individually-aligned single molecules. We essentially just use the crystal as a way to get a lot of single molecules, aligned in common orientations, into the beam.” With imperfect, disordered crystals, the continuous diffraction fills in the gaps and beyond the Bragg peaks, giving vastly more information than in normal crystallography. With this additional gain in information, the phase problem can be uniquely solved without having to resort to other measurements or assumptions. In the analogy of the Sudoku puzzle, the measurements provide enough clues to always arrive at the right answer.

    The best crystals are imperfect crystals

    This novel concept leads to a paradigm shift in crystallography — the most ordered crystals are no longer the best to analyse with the novel method. Instead, the best crystals are imperfect crystals. “For the first time we have access to single molecule diffraction – we have never had this in crystallography before,” he explains. “But we have long known how to solve single-molecule diffraction if we could measure it.” The field of coherent diffractive imaging, spurred by the availability of laser-like beams from X-ray free-electron lasers, has developed powerful algorithms to directly solve the phase problem in this case, without having to know anything at all about the molecule. “You don’t even have to know chemistry,” says Chapman, “but you can learn it by looking at the three-dimensional image you get.”

    To demonstrate their novel analysis method, the Chapman group teamed up with the group of Professor Petra Fromme from the Arizona State University (ASU), and other colleagues from ASU, University of Wisconsin, the Greek Foundation for Research and Technology – Hellas FORTH, and SLAC National Accelerator Laboratory in the U.S. They used the world’s most powerful X-ray laser LCLS at SLAC to X-ray imperfect microcrystals of a membrane protein complex called Photosystem II that is part of the photosynthesis machinery in plants.

    SLAC LCLS Inside
    Inside LCLS

    Including the continuous diffraction pattern into the analysis immediately improved the spatial resolution around a quarter from 4.5 Ångström to 3.5 Ångström (an Ångström is 0.1 nanometres). The obtained image gave fine definition of molecular features that usually require fitting a chemical model to see. “That is a pretty big deal for biomolecules,” explains co-author Dr. Anton Barty from DESY. “And we can further improve the resolution if we take more patterns.” The team had only a few hours of measuring time for these experiments, while full-scale measuring campaigns usually last a couple of days.

    The scientists hope to obtain even clearer and higher resolution images of photosystem II and many other macromolecules with their new technique. “This kind of continuous diffraction has actually been seen for a long time from many different poorly-diffracting crystals,” says Chapman. “It wasn’t understood that you can get structural information from it and so analysis techniques suppressed it. We’re going to be busy to see if we can solve structures of molecules from old discarded data.”

    Reference:
    Macromolecular diffractive imaging using imperfect crystals; Kartik Ayyer et al.; Nature (2016); DOI: 10.1038/nature16949

    See the full article here .

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    DESY is one of the world’s leading accelerator centres. Researchers use the large-scale facilities at DESY to explore the microcosm in all its variety – from the interactions of tiny elementary particles and the behaviour of new types of nanomaterials to biomolecular processes that are essential to life. The accelerators and detectors that DESY develops and builds are unique research tools. The facilities generate the world’s most intense X-ray light, accelerate particles to record energies and open completely new windows onto the universe. 
That makes DESY not only a magnet for more than 3000 guest researchers from over 40 countries every year, but also a coveted partner for national and international cooperations. Committed young researchers find an exciting interdisciplinary setting at DESY. The research centre offers specialized training for a large number of professions. DESY cooperates with industry and business to promote new technologies that will benefit society and encourage innovations. This also benefits the metropolitan regions of the two DESY locations, Hamburg and Zeuthen near Berlin.

     
  • richardmitnick 9:16 am on February 5, 2016 Permalink | Reply
    Tags: , , , X-ray Technology   

    From DESY: “Scientists film exploding nanoparticles” 

    DESY
    DESY

    2016/02/05
    No writer credit found

    Imaging nanoscale dynamics with unparalleled detail and speed

    Using a super X-ray microscope, an international research team has “filmed” the explosion of single nanoparticles. The team led by Tais Gorkhover from Technische Universität Berlin, currently working at the SLAC National Accelerator Laboratory in the U.S. as a fellow of the Volkswagen Foundation, and Christoph Bostedt from the Argonne National Laboratory and Northwestern University has managed to combine a temporal resolution of 100 femtoseconds and a spatial resolution of eight nanometres for the first time. A nanometre is a billionth of a metre, and a femtosecond is a mere quadrillionth of a second. For their experiments, the scientists used the so-called free-electron X-ray laser LCLS.

    SLAC LCLS Inside
    LCLS at SLAC

    The exposure time of the individual images was so short that the rapidly moving particles in the gas phase appeared frozen in time. Therefore, they did not have to be fixed on substrates as it is commonly done in other microscopy approaches. The team, including researchers from the Center for Free-Electron Laser Science CFEL at DESY, reports its results in the scientific journal Nature Photonics.

    Xenon nanoparticle exploding
    Three states of an exploding xenon nanoparticle. The ultra short flashes of the X-ray laser record these states as a so-called diffraction pattern. From these, the state of the sample can be calculated. Credit: Tais Gorkhover/SLAC

    Most imaging approaches are severely limited when a combination of high spatial resolution and extreme shutter speed is required. Ultrafast optical approaches have a rather coarse resolution due to the long wavelength. Conversely, electron microscopy can yield ultrahigh resolution but demands a rather long exposure time and it requires the particles being fixed to substrates. Therefore ultrafast processes in free nanometre-sized particles cannot be directly imaged with conventional methods. However, the ability to image and understand the dynamics in nanostructures and aggregates is of relevance in many fields, ranging from climate models to nanotechnology.

    The properties and dynamics of nanoparticles can significantly change when they are deposited on a substrate. To avoid any modification, the particles, made of frozen xenon and with a diameter of around 40 nanometres, were imaged during their flight through a vacuum chamber. “Using the intense light of an infrared laser, the nanoparticles where superheated and exploded,” explains DESY scientist Jochen Küpper, who is also a professor at the University of Hamburg and a member of the Hamburg Centre for Ultrafast Imaging (CUI). The explosion was imaged with ultrafast X-ray flashes at different time steps. Küpper’s group helped to implement this so-called pump-probe technique. “The experiment was repeated over and over with a new nanoparticle every time and slightly increased delay of the X-ray flash,” reports Lotte Holmegaard from Küpper’s CFEL group. Subsequently the images were assembled to a „movie“.

    „To our big surprise the exploding particles appeared to be shrinking with time instead of expanding as intuitively expected“ says Gorkhover. This unexpected result could be explained with theoretical models that describe the explosion as a melting process starting on the surface instead of a homogenous expansion. In this process, the solid part of the particle’s core gets smaller and smaller what causes the illusion of a shrinking particle.

    Another very interesting aspect of this new imaging approach is that it is possible to directly image the dynamics in single, free nanoparticles. Most time resolved studies are based on ensembles of many particles and averaging statements in which some important differences such as size and shapes of the particles get lost. “We have already demonstrated the importance to look at one particle at a time in earlier static experiments. Now this approach is also available for time-resolved studies,” says Gorkhover.

    “Our experiments yield unprecedented insight into the non-equilibrium physics of superheated nanoparticles. Moreover, they open the door for a multitude of new experiments where the ultrafast dynamics of small samples is important.“ explains Bostedt. Such dynamics may be of relevance in the formation of aerosols which are of major importance in climate models as they are in a large part responsible for absorption and reflection of sunlight. They may also be interesting for research on laser driven fusion in small targets or the rapidly developing area of nanoplasmonics in which the properties of nanoparticles are manipulated with intense light fields.

    Reference:
    Femtosecond and nanometre visualization of structural dynamics in superheated nanoparticles; Tais Gorkhover, Christoph Bostedt et al.; „Nature Photonics“, 2016; DOI: 10.1038/NPHOTON.2015.264

    See the full article here .

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    desi

    DESY is one of the world’s leading accelerator centres. Researchers use the large-scale facilities at DESY to explore the microcosm in all its variety – from the interactions of tiny elementary particles and the behaviour of new types of nanomaterials to biomolecular processes that are essential to life. The accelerators and detectors that DESY develops and builds are unique research tools. The facilities generate the world’s most intense X-ray light, accelerate particles to record energies and open completely new windows onto the universe. 
That makes DESY not only a magnet for more than 3000 guest researchers from over 40 countries every year, but also a coveted partner for national and international cooperations. Committed young researchers find an exciting interdisciplinary setting at DESY. The research centre offers specialized training for a large number of professions. DESY cooperates with industry and business to promote new technologies that will benefit society and encourage innovations. This also benefits the metropolitan regions of the two DESY locations, Hamburg and Zeuthen near Berlin.

     
  • richardmitnick 5:21 pm on January 29, 2016 Permalink | Reply
    Tags: , , X-ray Technology   

    From SLAC: “Tiniest Particles Shrink Before Exploding When Hit With SLAC’s X-ray Laser” 


    SLAC Lab

    January 29, 2016

    nanometer-sized clusters of xenon atoms (center) first shrink before exploding after being hit with very intense X-rays. In the experiment at LCLS
    Nanometer-sized clusters of xenon atoms (center) first shrink before exploding after being hit with very intense X-rays at LCLS.

    SLAC Experimental setup at LCLS used to determine that nanometer-sized particles first shrink before exploding after being hit with very intense X-rays.
    Experimental setup at LCLS used to determine that nanometer-sized particles first shrink before exploding after being hit with very intense X-rays. The researchers exposed tiny xenon clusters (injected from top left) to two consecutive X-ray pulses (green and red wavelets coming in from bottom left). The first pulse rapidly heats the cluster, while the second pulse probes how its structure changes over a period of 80 quadrillionths of a second. The structural changes are tracked with an X-ray detector (right). (SLAC National Accelerator Laboratory)

    Researchers assumed that tiny objects would instantly blow up when hit by extremely intense light from the world’s most powerful X-ray laser at the Department of Energy’s SLAC National Accelerator Laboratory. But to their astonishment, these nanoparticles initially shrank instead – a finding that provides a glimpse of the unusual world of superheated nanomaterials that could eventually also help scientists further develop X-ray techniques for taking atomic images of individual molecules.

    The experiments took place at the Linac Coherent Light Source (LCLS) X-ray laser, a DOE Office of Science User Facility. Its pulses are so bright that they can be used to turn solids into highly ionized gases, or plasmas, that blow up within a fraction of a second. Fortunately, for many samples researchers can take the data they need before the damage sets in – an approach that has been used to reveal never-before-seen details of a variety of samples relevant to chemistry, materials science, biology and energy research.

    The ultimate limits of this approach are, however, not well understood. One of the key visions for X-ray laser science is to image individual, one-of-a-kind particles with single X-ray pulses. To do so in a quantitative manner, researchers need to understand precisely how each molecule responds to the intense X-ray light. The new study, published today in Science Advances, provides an unexpected insight into this aspect.

    “So far, all models have assumed that a very small system would immediately explode when we pump a lot of energy into it with the X-ray laser,” says former LCLS researcher Christoph Bostedt, who is now at Argonne National Laboratory and Northwestern University. “But our experiments showed otherwise.”

    At LCLS, Bostedt and his fellow researchers exposed minuscule clusters of xenon atoms to two consecutive X-ray pulses. The clusters, which were merely three millionths of an inch across, were heated by the first pulse for 10 quadrillionths of a second, or 10 femtoseconds. The second pulse then probed the clusters’ atomic structures over the next 80 femtoseconds.

    “The unique nature of the LCLS X-ray pulse allowed us to create a freeze-frame movie of the response, with a resolution of about a tenth of the width of a single xenon atom,” says LCLS and Stanford University graduate student Ken Ferguson, who led the data analysis. The researchers believe that the effect is a result of how electrons, which were initially localized around individual xenon atoms, redistribute over the entire cluster after the first X-ray pulse.

    “This phenomenon had never been observed before, nor had it been predicted by any of the existing theories,” he says. “We expect it to have implications for many ultrafast X-ray laser experiments, especially those geared toward single-particle imaging with very intense X-ray pulses.”

    The research could benefit studies in other areas as well, such as investigations of warm dense matter – a state of matter between a solid and a plasma that exists in the cores of certain planets and is also important in the pursuit of nuclear fusion with high-power lasers.

    Other institutions involved in the study were Technical University of Berlin, Germany; Tohoku University, Japan; National Science Foundation BioXFEL Science and Technology Center, Buffalo; and Kyoto University, Japan.

    Citation: K. R. Ferguson et al., Science Advances, 29 January 2016 (10.1126/sciadv.1500837).

    See the full article here .

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    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.
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  • richardmitnick 4:56 am on January 22, 2016 Permalink | Reply
    Tags: , , SLAC LCLS MFX, X-ray Technology   

    From SLAC: “New MFX Experimental Station at LCLS Sees First X-ray Light” 


    SLAC Lab

    1.15.16
    No writer credit found

    Instrument Expands X-ray Laser’s Capability and Flexibility for Biological Experiments

    For the first time in three years, LCLS has added a new instrument to its set of experimental stations. Staff from Stanford and SLAC gathered on Jan. 12 in the X-ray laser’s Far Experimental Hall to celebrate the arrival of the first X-rays in the brand new MFX hutch. LCLS’s seventh instrument, MFX will expand the facility’s capability and capacity by generating more opportunities for all kinds of groundbreaking user experiments.

    Although MFX can support a variety of experimental settings, it was specifically designed for macromolecular femtosecond crystallography. This technique provides atomic-resolution X-ray images and ultrafast movies of biomolecules in action. It will aid researchers in unravelling crucial biological processes, from finding new ways of fighting disease to developing methods to harness solar energy similar to photosynthesis.

    “MFX is going to make a big difference for the biosciences community, which has a growing demand for X-ray laser studies,” said SLAC and Stanford researcher Soichi Wakatsuki, the principal investigator for the MFX grants that initiated the project. “The instrument will increase the number of biological experiments at LCLS and will allow us to do them more efficiently.”

    SLAC LCLS Far Experimental Hall
    LCLS’s new instrument for macromolecular femtosecond crystallography, MFX, is located in the X-ray laser’s Far Experimental Hall. (SLAC National Accelerator Laboratory)

    So far, studies of biological samples have taken place at several other LCLS instruments, including AMO and SXR, but primarily at XPP and CXI. Their versatile, multi-purpose research programs require frequent, time-consuming changes in the experimental setups and limit the time available for biostudies. MFX will help alleviate both issues.

    But the addition of the new experimental station will benefit more than just bio-interested users. Since the X-ray beam can now be distributed between more instruments than before, there will be more experimental time for non-MFX users as well. The new in-hutch instrumentation, which is the focus of ongoing and future R&D, is rapidly expanding the MFX scientific capabilities in new directions.

    Building the new hutch in the Far Experimental Hall took place over the past six months. Now, more equipment will be brought in to prepare for the first MFX user experiments in July.
    A Collaborative Effort

    “It only took a little more than two-and-a-half years from the initial idea for MFX to today’s first light,” said LCLS scientist and MFX project manager Sébastien Boutet. “None of this would have happened without the collaboration of many great people – technicians, designers, engineers, researchers and construction workers.”

    LCLS ALD Mike Dunne said, “MFX is a great example of the successful collaboration between Stanford, SLAC’s Biosciences Division, SSRL and LCLS, and it may be a model for future projects that bring people together to do something remarkable.”

    Similar statements were also made by others at the first-light event.

    Persis Drell, dean of the Stanford School of Engineering and former SLAC director, emphasized that it was the inspiration of researchers from both SLAC and Stanford that laid the ground for the new instrument, which will make LCLS more accessible to users from around the world.

    SSRL Science Director Britt Hedman pointed out that MFX is also a gateway for scientists who want to do new types of crossover experiments that make use of both X-ray light sources, LCLS and SSRL. On the SSRL side, MFX efforts are led by researcher Aina Cohen, who also oversaw the development of a broadly used experimental setup at XPP that will now be used at MFX.

    SLAC LCLS MFX
    SLAC LCLS MFX

    “Today’s first light is a major milestone, but it’s not the end of MFX construction yet,” Wakatsuki said. “In the near future, we’ll install advanced instrumentation capable of rapid and automated use of LCLS’s X-rays, and turn MFX into a highly optimized system that will further increase the scientific productivity of the facility.”

    The MFX project received financial support from the Department of Energy’s Office of Science, Biological and Environmental Research (BER) and Basic Energy Sciences (BES); the National Institute of General Medical Sciences; Stanford University and the Howard Hughes Medical Institute.

    See the full article here .

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