Tommaso Mazza
Daniele De Sanctis
Marie Jacquet
Luca Serafini
Few-fs to as X-ray pulses at the European XFEL: characterization and applications
Tommaso Mazza, Scientist in Gas Phase Soft X-Ray Physics , Scientific Instrument SQS, European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
tommaso.mazza@xfel.eu
Abstract: X-ray Free Electron lasers (XFELs) are light sources with brilliance exceeding third generation synchrotrons by several orders of magnitude, delivering pulses made of many X-ray photons and with very short durations.
Pulse durations reaching down to the sub-femtosecond regime, implemented in pump-probe setups either exploiting multipulse delivery schemes or synchronized external sources, give access to the natural time scale of electronic motion. This opens the way to extending time-resolved experiments from the recording of molecular movies which capture nuclear dynamics by means of different probes, to measurements in which electronic movies with the appropriate time resolution can be recorded, or even electronic control can be exerted.
The exceptionally high x-ray pulse energies which can be delivered by FELs, on the other hand, pushed already in early stages the quest for observing strong field effects at nm-sized wavelengths. It can be shown that effective access to the corresponding high intensity conditions can only be obtained with attosecond pulses, in a similar manner as decades ago sub-ps pulses gave access to strong field pheonomenology in the optical regime.
With the first generation ever of isolated attosecond pulses by HHG process dating back only 20 years, attosecond science is still in its infancy, with the most prolific efforts dedicated to the investigation of light generation mechanisms. FEL scientists belong well in the photonics community; yet, due to their well defined user-oriented mission, FELs have also a strong drive towards the development of a standard delivery of sub-fs x-ray pulses for user operation.
In my contribution I will report on the experience at the European XFEL with the use of sub-fs x-ray pulses delivered by the FEL undulators. I will briefly tell on the generation technique and I will then describe the metrology approaches we developed and implemented for their characterization. Finally, I will show some results on first applications and will discuss the scientific perspectives of the current developments.
Tommaso Mazza is Senior Instrument Scientist at the Small Quantum Systems Instrument at the European XFEL. After his PhD at the University of Milan (2007) he dedicated to studies on isolated metal clusters designing and performing experiments with optical lasers, synchrotron and FEL sources as post-doc at the University of Milan and visiting scientist at the IMRAM institute in Japan. In 2011 he joined the European XFEL, dedicating to the development of the SQS instrument from the very beginning, and extending his scientific activities to the study of atomic and molecular systems.
He currently has a senior role in the SQS group with advanced expertise on x-ray beam transport and diagnostics, ion and electron spectroscopy. His research activities focus on non-linear interaction of atoms with x-rays, molecular dynamics upon photoexcitation, structural dynamics of complex metal clusters, and metrology techniques for FEL sources.
Serial microsecond crystallography at the new ID29 at ESRF 4th generation source
Daniele De Sanctis, Principal beamline scientist at ID29, European Synchrotron Radiation Facility - ESRF, Grenoble, Auvergne-Rhône-Alpes, France
daniele.de_sanctis@esrf.fr
Abstract: Serial macromolecular crystallography (SMX) has emerged as a highly effective technique for uncovering the structures of biological macromolecules at room temperature (RT). While microfocus beamlines at third-generation synchrotrons are invaluable, their capacity for data acquisition is often restricted to the millisecond time scale due to limitations in photon flux and detector capabilities. The newly developed ID29 beamline at the European Synchrotron (ESRF), a flagship project of the upgraded Extremely Brilliant Source (EBS), was specifically engineered to capitalize on the attributes of the ESRF's fourth-generation source. ID29 stands out as the pioneer beamline dedicated to room temperature serial microsecond (µs) crystallography (RT-SµX) utilizing truly µs-pulsed X-rays. Its distinctive features, along with a compact and versatile diffractometer, facilitate swift sample environment changes accommodating various solid supports and three types of high-viscosity extruders (HVE). Our study underscores the essential combination of pulsed beams, a rapid JungFrau4M detector, and fully synchronized data collection setups for efficient RT-SµX or serial crystallography experiments. We demonstrate how the unique beam characteristics, made possible by the new ESRF 4th generation source, pave the way for microsecond time-resolved crystallography, capable of obtaining fully interpretable electron density map from a limited number of merged frames. Looking ahead, the demonstrated capabilities of room-temperature serial microsecond crystallography at ID29 are poised to find broad utility at forthcoming fourth-generation synchrotron sources worldwide.
After obtaining his PhD at the university of Genova in protein crystallography in the study of hexacoordinated globins, Daniele de Sanctis moved to the ITQB at the new university of Lisbon to pursue research on bacterial sugar metabolism and eventually joined the ESRF Structural Biology Group as beamline scientist. He is currently senior scientist responsible for the design construction and operation of the new ID29 beamline dedicate to time resolved serial macromolecular crystallography. In addition to the development of novel methods in the field, his current research interests focuses on study enzymatic reactions in crystals to exploit time dependent structural conformations and reactions pathways.
Challenges for intense and compact Compton sources - First X-ray production at ThomX
ThomX collaboration, Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 ORSAY, France
marie.jacquet@ijclab.in2p3.fr
Abstract: Currently, there are increasing demands for access to bright, tunable, monochromatic X-ray sources in the fields of medicine (imaging and therapy), cultural heritage studies and preservation, and industrial applications (materials science). Synchrotrons are the best light sources in terms of energy tuning and brightness but there are strong constraints on their use and diffusion, such as their size, construction and operating costs and the high demand for beam times. Thanks to the increasing power of lasers, for a moderate cost and dimensions compatible with an experimental hall, compact Compton scattering sources can now provide a quasi-monochromatic X-ray beam of high flux and high brightness, compared to current laboratory sources (X-ray tubes).
The French project ThomX is a demonstrator of such a source. The machine is installed at the Irène Joliot-Curie laboratory (IJCLab) on the Orsay campus of Université Paris-Saclay and is designed to produce a total average flux of 10^12-10^13 ph/s in an energy range from 45 keV to 90 keV with an average brightness of 10^10-10^11 ph/s /mm2/mrad2/0.1%bw. To achieve these performances, the electron bunches and laser pulses are stored respectively in a storage ring and a high-gain Fabry-Perot cavity. The first X-rays were produced in July 2023.
In this context, I will start by introducing the state of the art of the compact high-flux Compton sources, then I will give an overview of the ThomX source, from its construction to its commissioning, and outline the latest results and next steps to reach nominal flux.
During her PhD in the 90s and until the 2010s, Marie Jacquet carried out research in high-energy physics at large particle colliders (simulations of Standard Model processes, search for new particles, detector calibration, data analysis, Compton polarimetry): at the Large Electron-Positron Collider (LEP) at CERN, then at the Hadron-Electron Ring Accelerator (HERA) in Hamburg.
From the 2010s, she works on the Compton polarimeter at HERA and the expertise of the IJCLab laboratory in this area brought her to the field of Compton X-ray sources, then led her to join the ThomX project carried out by IJCLab (formerly LAL). Today, Marie Jacquet is the scientific manager of ThomX.
A long journey into collisional radiation sources: from Thomson back-scattering to electron-photon colliders and beyond, towards Full Inverse Compton Scattering.
Luca Serafini, scientific collaborator at INFN-Milan Department, former research director and leader of INFN-STAR project.
luca.serafini@mi.infn.it
Abstract: Collisional radiation sources are those based on electron-(real)photon interactions, whose main paradigm is represented by Inverse Compton Scattering X and Gamma ray sources. Complementary to undulatory radiation sources, whose main paradimgs are Synchrotron light sources and FELs. Although the first interest in inverse Thomson or Compton scattering arised in the ‘40s around the atomic bomb development and in the just born astro-physical community, real experiments with lasers and particle accelerators were conducted only in the ’60s. But in order to achieve X and Gamma ray photon beams of interest to users, with adequate performances of brilliance, fluxes and spectral densities, we had to wait until almost 15 years ago for the mature development of two enabling technologies: CPA lasers and high brightness photo-injectors. They allowed to boost the achievable luminosity of electron-photon colliders (as Inverse Thomson/Compton scattering sources are) by orders of magnitude, and they opened the era of ICS devoted to user facilities like STAR, serving advanced radiological imaging applications (with micro-tomography), nuclear photonics and photo-nuclear physics, and, more upfront, secondary beam sources of low emittance muon and positron beams. As a latest development, recent studies of extreme Inverse Compton scattering showed possible new regimes of interactions where the total transfer of energy/momentum from the electron to the scattered photon can be achieved, opening new opportunities of spectral purification effects and full stopping of relativistic electrons in vacuum, possibly impacting the world of cosmic Gamma-ray sources and possibly enabling the generation of quantum gravitational effects.
Luca Serafini is a particle accelerator physicist active in the field of radiation sources, with advanced expertise in high brightness electron beams and electron-photon beam-beam interactions. In particular, he invented the velocity bunching technique and he firstly derived the RF transport matrix. More recently, the first study of two-way acceleration and of Symmetric Compton Scattering, leading to the new regime of Full Inverse Compton Scattering. Former leader of INFN-STAR project, he retired as research director at INFN, but he is still affiliated to INFN-Milan Department as scientific collaborator.