First megahertz rate timing jitter observed

A report published today in the Journal Optica demonstrates accurate synchronisation of optical and X-ray lasers crucial for pump-probe experiments at XFEL. These snapshots taken during a reaction are stitched together to make molecular movies.

One of the ultimate goals for scientists using state-of-the-art X-ray free-electron lasers such as European XFEL is to be able to film the details of chemical and biological reactions. By stitching together a series of snapshots taken at different time intervals during a reaction, a molecular movie can be made of the process. So called pump-probe experiments use a precisely synchronised optical laser to trigger a reaction (the ‘pump’), while the X-ray laser takes a snapshot of the molecular structure at defined times during the reaction (the ‘probe’).

European XFEL now generates the ultrafast and ultra-intense light pulses needed to capture these processes that occur on extremely short timescales. The pulses of X-ray light generated by European XFEL are each less than a few millionths of a billionth of a second, or a few femtoseconds – fast enough to capture the series of events in a biological or chemical reaction. An accurate synchronization of the X-ray and optical laser pulses at these timescales is, however, challenging. Furthermore, tiny variations in the alignment and path travelled by the laser pulses caused, for example, by fluctuations in air pressure, or expansion in the electrical cables, have a relatively large impact on the accuracy of this experimental set-up. This variation is known as ‘timing jitter’. For pump-probe experiments to be successful, the jitter must be kept to a minimum, and be accurately characterized so that scientists can take it into account when assessing their data.

Read more on the European XFEL website

Image : The XPB/SFX instrument at European XFEL.

Credit: European XFEL / Jan Hosan

Day of Light: 60th anniversary of the laser

The invention of the laser 60 years ago has transformed science and everyday life.

Sixty years after the first laser was operated on 16 May 1960 by Theodore Maiman at Hughes Research Laboratories in California, lasers have revolutionized everyday life as well as science. Lasers are also fundamental for research at the European XFEL. A public event on the European XFEL campus planned to celebrate this anniversary has been postponed to a later date.

When the world’s biggest X-ray laser and one of the planet’s brightest light sources, the European XFEL, started operation in 2017, it was the culmination of several decades of scientific progress in laser and X-ray laser technology. Lasers operating in the visible wavelength range were invented in the 1960s. In these lasers, radiation is generated from electron transitions in atoms or molecules. The light emitted is then continuously amplified between mirrors. This makes it comparatively easy to produce high-quality laser light, and many applications now shape our everyday lives. Examples range from impressive light installations, to high precision surgical instruments, broadband telecommunication, components in the electrical devices we carry in our pockets, and the laser pointer we use during presentations.

Read more on the XFEL website

Image: The optical laser system for pump-probe experiments in the laser lab.

Credit: European XFEL / Jan Hosan

Super laser delivered to European XFEL

High Energy laser will enable study of exoplanet interiors.

A keenly awaited piece of high-tech equipment has been delivered to European XFEL. The high repetition rate, high-energy laser, DiPOLE 100-X, was developed in the UK by scientists and engineers at the Science and Technology Facilities Council’s Central Laser Facility (CFL) as part of the UK contribution to the facility. This unique laser, developed within the framework of the HiBEF user consortium, will be used at the instrument for High-Energy Density (HED) science at European XFEL to generate extreme temperatures and pressures in materials. The atomic structure and dynamics of these extreme states of materials can then be studied using the extremely bright and intense X-ray pulses produced by the European XFEL. This experimental set-up will enable scientists to create conditions similar to the interior of exoplanets with temperatures of up to 10,000°C, and pressures of up to 10,000 tons per square centimeter – similar to the weight of 2000 adult elephants concentrated onto the surface of a postage stamp!

>Read more on the European XFEL website

Image: The HED instrument at European XFEL.
Credit: European XFEL/Jan Hosan

Shaping attosecond waveforms

Scientists show how to control attosecond light pulses at a free-electron laser.

Chemical reactions and complex phenomena in liquids and solids are determined by the movement and rearrangement of electrons. These movements, however, occur on an extremely short timescale, typically only a few hundred attoseconds (1 attosecond =10-18 s or one quintillionth of a second).  Only light pulses of a comparable duration can be used to take snapshots of the dynamics of electrons. An international team of researchers led by Guiseppe Sansone from the University of Freiburg and including scientists from European XFEL have now, for the first time, been able to reliably generate, control and characterize such attosecond light pulses from a free-electron laser.

“These pulses enable us to study the first moment of the electronic response in a molecule or crystal,” explains Sansone. “With the ability to shape the electric field enables us to control electronic movements – with the long-term goal of optimising basic processes such as photosynthesis or charge separation in materials.”

>Read more on the European XFEL website

Image: Scientists have been able to shape the electric field of an attosecond light pulse.
Credit: Jürgen Oschwald and Carlo Callegari

Record participation at user meetings of the Hamburg research light sources

More than 1300 participants from 28 countries have registered

For this year’s users’ meetings of the Hamburg X-ray light sources, more participants have registered than ever before: More than 1300 scientists from 28 countries will come to discuss research with DESY’s X-ray source PETRA III, the free-electron laser in Hamburg FLASH and the X-ray laser European XFEL for three days starting this Wednesday. The jointly organised users’ meetings of DESY and European XFEL are the largest gathering of this kind worldwide.

“The steadily increasing number of participants from Germany and abroad shows the great importance of the Hamburg research light sources for the national and international scientific community,” says DESY’s Director for Photon Science, Edgar Weckert. “Hamburg is one of the X-ray capitals of the world.” The brilliant X-ray light from the powerful particle accelerators provides detailed insights into the structure and dynamics of matter at the atomic level. It can be used, for example, to decipher the structure of biomolecules, illuminate innovative materials, film chemical reactions and simulate and study the conditions inside planets and stars.

At the European X-ray laser European XFEL, all six scientific experiment stations are in operation since June. “Our users’ experiences and expertise are crucial for shaping the future of our science and facility”, says European XFEL managing director Robert Feidenhans’l. “The annual users’ meeting, therefore, is an extremely valuable opportunity for users and scientists who work at our facilities to share their experiences of doing experiments at the instruments, and talk about ideas for further development.” In 2019, 890 scientists from 255 institutes in 28 countries participated in experiments at the facility.

> Read more on the PETRA III and FLASH website

> Please find here another article on the European XFEL website

Picture: The jointly organised users’ meetings are the largest gathering of this kind worldwide.
Credit: DESY, Marta Mayer

First molecular movies at European XFEL

Scientists show how to use extremely short X-ray pulses to make the first movies of molecular processes at the European XFEL.

In a paper published today in Nature Methods, scientists show how to effectively use the high X-ray pulse repetition rate of the European XFEL to produce detailed molecular movies. This type of information can help us to better understand, for example, how a drug molecule reacts with proteins in a human cell, or how plant proteins store light energy.

Traditional structural biology methods use X-rays to produce snapshots of the 3D structure of molecules such as proteins. Although valuable, this information does not reveal details about the dynamics of biomolecular processes. If several snapshots can be taken in fast enough succession, however, these can be pasted together to make a so-called molecular movie. The high repetition rate of the extremely short X-ray pulses produced by the European XFEL makes it now possible to collect large amounts of data to produce movies with more frames than ever before. An international group of scientists have now worked out how to make optimal use of the European XFEL’s very high X-ray repetition rate to make these molecular movies at the facility in order to reveal unprecedented details of our world.

>Read more on the European XFEL website

Image: Artistic visualisation of a serial crystallography experiment. A stream of crystalline proteins are struck by an optical laser that initiates a reaction. Following a short delay the X-ray laser strikes the crystals. The information recorded about the arrangement of the atoms in the protein is used to reconstruct a model of the structure of the protein.
Credit: European XFEL / Blue Clay Studios

Using European XFEL to shed light on photosynthesis

First membrane protein studied at European XFEL

In a paper now published in Nature Communications an international group of scientists show that the fast X-ray pulse rate produced by the European XFEL can be used to study the structure of membrane proteins such as those involved in the process of photosynthesis. These results open up eagerly awaited experimental opportunities for scientists studying these types of proteins.

Large proteins and protein complexes are difficult to study with traditional structural biology approaches. Large protein complexes, such as those that sit across cell membranes and regulate traffic in and out of cells, are difficult to crystalize and generally only produce small crystals that are hard to analyse. The extremely fast X-ray pulses generated by European XFEL now enable scientists to collect large amounts of data from a stream of small crystals to develop detailed models of the 3D structure of these proteins.

>Read more on the European XFEL website

Image (extract, full illustration in the article): Graphic shows the basic design of a serial femtosecond crystallography experiment at European XFEL. X-ray bursts strike crystallized samples resulting in diffraction patterns that can be reassembled into detailed images.
Credit: Shireen Dooling for the Biodesign Institute at ASU

All SQS experiment stations up and running

Three new experiment stations expand the scientific possibilities in the field of soft X-ray science.

The soft X-ray instrument for Small Quantum Systems (SQS) welcomed its first users at the end of 2018. Now, almost a year later, the SQS team and collaborators have completed their ambitious plan to install and commission all three experiment stations, each specifically designed for different types of experiments and samples, ranging from atoms and small molecules to large clusters, nanoparticles and biomolecules. We look at how the instrument has developed during the past year, how important collaboration has been for the success of SQS so far, and what lies ahead.

>Read more on the European XFEL website

Image: SQS scientist Rebecca Boll makes final adjustments on the AQS experiment station before the first users arrive at the end of 2018.
Credit: European XFEL

Q&A with Sakura Pascarelli, new scientific director at European XFEL

European XFEL’s new scientific director talks about her career, her new role and her love for swimming.

On 1 September Sakura Pascarelli joined the European XFEL from the ESRF. In her role as scientific director she is responsible for the development of the four hard X-ray instruments. She spoke to Rosemary Wilson about her career, her new role and her love for swimming.

How did you get into science?

I spent part of my childhood in Burma and Indonesia. The American school system there enabled you to do lessons at your level, meaning you stayed interested and engaged. I really liked maths which I did with kids a few years older than me. I remember also doing experiments. I liked seeing things explode and break and try to understand why. Later on in Italy, I studied physics – not because I was particularly talented, but because I enjoyed it.

You joined ESRF at a time when the facility was still being built. What parallels can you see between that time, and now here at European XFEL?

I went to the ESRF to build one of the first beamlines there. We didn’t know what we would be able to discover or measure with this new machine. Here at European XFEL I see some of that same excitement. That opportunity taught me so much about instrumentation, and coordinating the construction of a beamline. But it is a different world now. Back then a good scientist with a solid background in physics, X-ray optics or instrumentation, could build a group and build a beamline. That is not possible here. This is so much more complicated. Here you need experts in X-rays, lasers, electronics, detectors. We don’t really know how to measure a femtosecond pulse let alone synchronise it with another laser! To run these instruments we need group leaders who are really good managers. This is so important. It is no longer enough for someone to be just a good scientist. At European XFEL we need to make sure the groups are well structured, well managed and that the people are happy. That might be difficult in the beginning when things don’t work, but when people see that their work is recognized, satisfaction and productivity increases.

>Read more on the European XFEL website

Image: European XFEL

Two years of user operation in numbers

1200 users, 60 experiments and 6 petabytes of data since operation began.

September 1 marks two years since the official opening and start of user operation at European XFEL. With the scheduled expansion from two to six operational instruments, the facility has expanded its experimental capacity and possibilities significantly during the past two years. At the same time, both the performance of the X-ray free-electron laser and instruments was continually improved. The scientific community shows strong interest in experiments at the new facility, with a total of 363 submitted proposals during this period, of which 98 were awarded beamtime. In total, 1200 users from across the world came to Schenefeld for their research. As the facility continues to be developed, even more time will be available for user experiments in the future.

>Read more on the European XFEL website

Image: Laser installation on the European XFEL campus in 2017 highlighting the five underground tunnels.
Credit: The European XFEL (Germany)

First high-speed hard X-ray microscopic movies at a free-electron laser

New technique enables investigation of industrially relevant materials and processes in motion.

A group of researchers has for the first time performed high-speed microscopy using an X-ray laser at the European XFEL in Schenefeld near Hamburg, Germany. The method allows for observations of processes that take place at speeds up to a few kilometres per second, paving the way for 3D microscopic movies of fast phenomena, with important potential industrial applications. Such movies could show what happens during complex processes with a resolution at the sub-micrometre level, which is less than the diameter of a human hair, while also teasing out hidden internal details. While most other applications of X-ray lasers are based on the short wavelength of their X-ray flashes, making images that reach atomic resolution possible, this use takes advantage of the penetrating properties of X-rays. The resulting images, which are on the microscopic rather than atomic scale, reveal the internal structures of complex processes such as fluid cavitation at high speed. The research, which has been published in the journal Optica, was led by scientists from the Center for Free-Electron Laser Science (CFEL) in Hamburg (a collaboration between DESY, Universität Hamburg, and the Max Planck Society) and the European XFEL and involves scientists from P.J. Šafárik University in Slovakia, Lund University in Sweden, Diamond Light Source and University College London in the UK, the Karlsruhe Institute of Technology in Germany, and the European Synchrotron Radiation Facility (ESRF) in France.

>Read more on the European XFEL website

Illustration: X-ray microscopic image of a bursting glass capillary, taken at the SPB/SFX instrument at the European XFEL. The image on the left shows the image produced from the experiment. The middle version shows the direction of the motion of debris, showing the spinning glass fragments and details of turbulence in the water. The right version shows the velocity of the debris in metres per second. Download to view video here.
Credit: European XFEL

Third user run successfully completed, fourth starting soon

Around 600 scientists visit the facility for experiments during user period.

The third user experiment period at European XFEL, which ran from November 2018, was successfully completed in June 2019. The X-ray beam was available for experiments for a total of 18 weeks. Twenty-eight user experiments were carried out at all six instruments, and 599 users were welcomed to the facility.

While only two instruments were operational at the beginning of the run, a further four started operation during the period, so that all six instruments were operational by the end of the run. Many other systems also had to first be prepared so that everything worked together. This included the accelerator and electron beam system, which could distribute the beam on demand to the different light sources. Other systems that were optimized to reach the goal of parallel operation of all three beamlines included the X-ray optics and diagnostic systems in the tunnels, elements at the instruments themselves that deal with the X-ray beam and specimen delivery, detectors, and software and data storage systems.

>Read more on the European XFEL website

Picture: The MID experiment station was one of the four to begin user operation during user run 3.
Credit: European XFEL / Jan Hosan

Fastest soft X-ray camera in the world installed at European XFEL

DSSC detector will expand scientific capabilities of soft X-ray instruments

At European XFEL near Hamburg the world’s fastest soft X-ray camera has successfully been put through its paces. The installation, commissioning and operation of the unique detector marks the culmination of over a decade of international collaborative research and development. The so-called DSSC detector, designed specifically for the low energy regimes and long X-ray wavelengths used at the European XFEL soft X-ray instruments, will significantly expand the scientific capabilities of the instrument for Spectroscopy and Coherent Scattering (SCS) where it is installed. It will enable ultrafast studies of electronic, spin and atomic structures at the nanoscale making use of each X-ray flash provided by European XFEL. At the end of May, the first scientific experiments using the DSSC were successfully conducted at SCS.

> Read more on the European XFEL website

Image: European XFEL management and staff celebrate the successful installation and commissioning of the DSSC detector at the SCS instrument. The DSSC can be seen behind the group in the centre of the photo. From left to right European XFEL managing director Nicole Elleuche, Detector group leader Markus Kuster, European XFEL managing director Robert Feidenhans’l, DSSC consortium leader Matteo Porro, detector scientist Monica Turcato, SCS group leader Andreas Scherz. Copyright European XFEL

European XFEL plans ultrahigh-speed network connection to Poland

Data from experiments will also be processed at partner institute NCBJ in Otwock-Świerk.

European XFEL and the National Center for Nuclear Research (NCBJ) in Otwock-Świerk near Warsaw plan to establish the first ultrahigh-speed connection for research data between Germany and Poland. The aim is for the new Supercomputing Center at NCBJ to be used for the processing and analysis of data generated at the European XFEL. The dedicated network connection between the DESY Computer Center, which hosts European XFEL’s primary data, and NCBJ will feature a data transfer rate of 100 gigabits per second (Gbit/s). With the exception of the higher-speed connection to DESY, that is approximately 100 times faster than the current typical Internet connection between European XFEL and other research institutes, through which the transfer of data for an average experiment at the facility would take about a month. In comparison, household high-speed Internet connections can typically manage about 250 Mbit/s for a download. This makes this new connection at least 400 times faster.
For the installation of the new high-speed data connection, the German National Research and Education Network (DFN), the Supercomputing and Networking Center at the Institute for Bioorganic Chemistry in Poznań (PSNC), the Research and Academic Computer Network National Research Institute (NASK), and Deutsches Elektronen-Synchrotron (DESY) will also take part alongside European XFEL and NCBJ. At the end of May this year, the partners signed a Memorandum of Understanding that will serve as the basis and starting point for establishing the new high-speed connection. It can largely be built on existing technical infrastructure, but certain specific components will have to be added. For example, the connection between the German and Polish research networks will be enabled by the European University Viadrina in Frankfurt an der Oder and the neighbouring Polish city of Słubice.

>Read more on the European XFEL website

Image: At European XFEL at peak user operation times, up to a petabyte of data can be produced per week.
Credit:  European XFEL / Jan Hosan

How morphing materials store information

Experiments at SLAC’s X-ray laser reveal in atomic detail how two distinct liquid phases in these materials enable fast switching between glassy and crystalline states that represent 0s and 1s in memory devices.

Instead of flash drives, the latest generation of smart phones uses materials that change physical states, or phases, to store and retrieve data faster, in less space and with more energy efficiency. When hit with a pulse of electricity or optical light, these materials switch between glassy and crystalline states that represent the 0s and 1s of the binary code used to store information.
Now scientists have discovered how those phase changes occur on an atomic level.
Researchers from European XFEL and the University of Duisburg-Essen in Germany, working in collaboration with researchers at the Department of Energy’s SLAC National Accelerator Laboratory, led X-ray laser experiments at SLAC that collected more than 10,000 snapshots of phase-change materials transforming from a glassy to a crystalline state in real time.

>Read more on the LCLS at SLAC website

Image: The research team after performing experiments at SLAC’s Linac Coherent Light Source X-ray laser.
Credit: Klaus Sokolowski-Tinten/University of Duisburg-Essen)

Please read also the article published on the EUXFEL website:
Rigid bonds enable new data storage technology

All six European XFEL instruments now operational

User experiments started at instrument for High Energy Density.

The first experiments have now started at the instrument for High Energy Density (HED) experiments. HED is the sixth and thereby last instrument of European XFEL’s current design configuration to start user operation. With six instruments on three SASE beamlines operational, European XFEL now has the capacity to host three times as many user experiments as compared to when operation began in 2017.
HED combines hard X-ray FEL radiation and the capability to generate matter under extreme conditions of pressure, temperature or electric field. HED will be used for studies of matter occurring inside exoplanets, of new extreme-pressure phases and solid-density plasmas, and of structural phase transitions of complex solids in high magnetic fields. The HED instrument is built in close collaboration with the HiBEF consortium led by Helmholtz Zentrum Dresden-Rossendorf (HZDR).
Next operation goals involve further increasing the capabilities and experiment portfolio of the instruments, increasing the amount of beamtime available for users at the six instruments and achieving successful parallel user operation of all three SASE beamlines. Parallel user operation is expected to start later this year.

>Read more on the European XFEL website

Image: The first users at the HED instrument.
Credit: European XFEL