Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 


Study provides recipe for 'supercharging' atoms with X-ray laser

Researchers using the Linac Coherent Light Source (LCLS) at the U.S. Department of Energy's (DOE) SLAC National Accelerator Laboratory have found a way to strip most of the electrons from xenon atoms, creating a "supercharged," strongly positive state at energies previously thought too low.

The findings, which defy expectations and theory, could help scientists deliberately induce the high levels of damage needed to study extreme states of matter or ward off damage in samples they're trying to image. The results were reported this week in Nature Photonics.

The ultra-bright X-ray laser pulses of the Linac Coherent Light Source at SLAC National Accelerator Laboratory can be used to strip electrons away from atoms, creating ions with strong charges. The ability to interact with atoms is critical for making the highest resolution images of molecules and movies of chemical processes.

Credit: Greg Stewart/SLAC National Accelerator Laboratory

Specialized equipment known as the CAMP chamber, pictured here, played a key role in advanced research at SLAC's free-electron laser, the Linac Coherent Light Source. A new paper details experiments with CAMP that observed a record supercharged state in xenon atoms. The equipment was on loan to SLAC through a collaboration with the Max Planck Society Advanced Study Group.

Credit: Brad Plummer/SLAC National Accelerator Laboratory

While the powerful X-rays of LCLS inevitably destroy the samples being studied, delaying damage – even for millionths of billionths of a second – can prove critical in producing detailed images and other data.

"Our results give a 'recipe' for maximizing the loss of electrons in a sample," said Daniel Rolles, a researcher for the Max Planck Advanced Study Group at the Center for Free-Electron Laser Science in Hamburg, Germany, who led the experiments. "For instance, researchers can use our findings if they're interested in creating a very highly charged plasma. Or, if the supercharged state isn't part of the study, they can use our findings to know what X-ray energies to avoid."

Just as a stretched guitar string can vibrate and sustain a note, a specific tuning of the laser's properties can cause atoms and molecules to resonate. The resonance excites the atoms and causes them to shake off electrons at a rate that otherwise would require higher energies.

While it is common knowledge that triggering resonances in atoms will affect their charged states, "it was not clear to anybody what a dramatic effect this could have in heavy atoms when they are being ionized by a source like LCLS," Rolles said. "It was the highest charge state ever observed with a single X-ray pulse, which shows that the existing theoretical approaches have to be modified."

The team had previously used a laser facility in Germany to expose various atoms and molecules to pulses of ultraviolet light, and was eager to use the higher-energy LCLS for further studies.

"The LCLS experiment pushed the charged state to an unprecedented and unexpected extreme – more than doubling the expected energy absorbed per atom and ejecting dozens of electrons," said Benedikt Rudek from the Max Planck Advanced Study Group, who analyzed the data.

In addition to creating or avoiding supercharged plasma states in experiments, Rolles said the "dramatic change" caused by resonance in the absorption of X-ray energy could someday be exploited to improve the resolution of images captured in LCLS experiments.

"Most biological samples have some heavy atoms embedded, for instance," Rolles said, and in some experiments, avoiding the resonance trigger might prevent rapid damage to those atoms.

The researchers have since done similar LCLS experiments involving the heavy element krypton and molecular systems that contain other heavy atoms, said Artem Rudenko of Kansas State University, who led a recent follow-up experiment.

The team's precise measurements were made possible by a sophisticated experimental station built by the Max Planck Advanced Study Group in Germany. In total, the equipment weighed about 11 tons and was shipped to SLAC in 40 crates. It stayed at LCLS for three years and was used in more than 20 experiments ranging from atomic and molecular physics to material sciences and bio-imaging.

"Reassembling this machine at LCLS within one month and then commissioning it and doing a science experiment in only seven days was an absolutely incredible feat," said Rolles.

The research team included scientists from 19 research centers, including: Max Planck Advanced Study Group and several Max Planck institutes, PNSensor GmbH, Technical University of Berlin, Jülich Research Center, University of Hamburg and Physikalisch-Technische Bundesanstalt in Germany; SLAC and Western Michigan and Kansas State universities in the U.S.; University of Pierre and Marie Curie and National Center for Scientific Research in France; and Kyoto and Tohoku universities in Japan.

LCLS is supported by DOE's Office of Science.

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 U.S. Department of Energy Office of Science. To learn more, please visit

DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit

Andy Freeberg | EurekAlert!
Further information:

More articles from Process Engineering:

nachricht Water pathways make fuel cells more efficient
24.09.2015 | Paul Scherrer Institut (PSI)

nachricht Infrared heat helps to get a good grip
22.09.2015 | Heraeus Noblelight GmbH

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Weltrekord am TRIGA Mainz: 20.000 Pulse in 50 Jahren

Forschungsreaktor hat Anfang Oktober einen neuen Meilenstein erreicht

Der Forschungsreaktor TRIGA an der Johannes Gutenberg-Universität Mainz (JGU) hat zwei Monate nach den Feierlichkeiten zu seinem 50-jährigen Bestehen einen...

Im Focus: Startschuss für eine neue Ära der Präzisionsastronomie

Für die MICADO-Kamera, das Instrument mit dem das European Extremely Large Telescope (E-ELT) seine ersten Bilder machen wird, beginnt eine neue Phase: In einer gemeinsamen Absichtserklärung (Memorandum of Understanding) auf der „Kick-off“-Konferenz in Wien bestätigten die Partner in Deutschland, Frankreich, den Niederlanden, Österreich und Italien ihre Teilnahme am Projekt. Zwei Wochen zuvor, am 18. September, hatten das Konsortium und die Europäische Südsternwarte (ESO), die das Teleskop baut, den entsprechenden Kooperationsvertrag unterzeichnet. Nach diesen Meilensteinen tritt das Projekt nun in die Designphase ein.

Als erste, dedizierte Kamera für das E-ELT wird MICADO beugungsbegrenzte Abbildungen bei Nah-Infrarot-Wellenlängen (Wärmestrahlung) mit dem Riesenteleskop...

Im Focus: Kick-off for a new era of precision astronomy

The MICADO camera, a first light instrument for the European Extremely Large Telescope (E-ELT), has entered a new phase in the project: by agreeing to a Memorandum of Understanding, the partners in Germany, France, the Netherlands, Austria, and Italy, have all confirmed their participation. Following this milestone, the project's transition into its preliminary design phase was approved at a kick-off meeting held in Vienna. Two weeks earlier, on September 18, the consortium and the European Southern Observatory (ESO), which is building the telescope, have signed the corresponding collaboration agreement.

As the first dedicated camera for the E-ELT, MICADO will equip the giant telescope with a capability for diffraction-limited imaging at near-infrared...

Im Focus: Locusts at the wheel: University of Graz investigates collision detector inspired by insect eyes

Self-driving cars will be on our streets in the foreseeable future. In Graz, research is currently dedicated to an innovative driver assistance system that takes over control if there is a danger of collision. It was nature that inspired Dr Manfred Hartbauer from the Institute of Zoology at the University of Graz: in dangerous traffic situations, migratory locusts react around ten times faster than humans. Working together with an interdisciplinary team, Hartbauer is investigating an affordable collision detector that is equipped with artificial locust eyes and can recognise potential crashes in time, during both day and night.

Inspired by insects

Im Focus: Heuschrecken am Steuer: Uni Graz erforscht Kollisionsdetektor nach Vorbild von Insektenaugen

Selbstfahrende Autos könnten in absehbarer Zukunft auf unseren Straßen unterwegs sein. Ein innovativer Fahrzeugassistent, der bei Kollisionsgefahr das Steuer übernimmt, wird gerade in Graz erforscht. Manfred Hartbauer vom Institut für Zoologie der Karl-Franzens-Universität hat sich die Basis dafür in der Natur abgeschaut: Wanderheuschrecken können in brenzligen Verkehrssituationen etwa zehnmal schneller reagieren als Menschen. In Zusammenarbeit mit einem interdisziplinären Team erforscht er einen kostengünstigen Kollisionsdetektor, der mit künstlichen Heuschrecken-Augen ausgestattet ist und drohende Zusammenstöße bei Tag und Nacht rechtzeitig erkennen kann.

Tierisches Vorbild

Alle Focus-News des Innovations-reports >>>



im innovations-report
in Kooperation mit academics

Wasserstoff-Speicher als Wegbereiter für die Energiewende

08.10.2015 | Veranstaltungen

Herbstzeit ist Weiterbildungszeit - Von Stressbiologie bis Täter-Opfer Ausgleich

08.10.2015 | Veranstaltungen

Energieforum 2015: Was können Wasserstofftechnologien leisten?

08.10.2015 | Veranstaltungen

Weitere VideoLinks >>>
Aktuelle Beiträge

Eye-Tracking: Erstmals Blickmuster von Wellenreitern in standardisierter Umgebung erfasst

08.10.2015 | Kommunikation Medien

Photonen als Treibstoff für elektrischen Strom

08.10.2015 | Energie und Elektrotechnik

Weltrekord am TRIGA Mainz: 20.000 Pulse in 50 Jahren

08.10.2015 | Physik Astronomie