Hazem Yousef
A5012868174- Advanced X-ray Imaging Techniques
- Medical Imaging Techniques and Applications
- Advanced Electron Microscopy Techniques and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced X-ray and CT Imaging
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- CCD and CMOS Imaging Sensors
- nanoparticles nucleation surface interactions
- X-ray Diffraction in Crystallography
- Particle Accelerators and Free-Electron Lasers
- Crystallization and Solubility Studies
- Nuclear Physics and Applications
- Atomic and Subatomic Physics Research
- Advancements in Photolithography Techniques
- Crystallography and Radiation Phenomena
- Quantum, superfluid, helium dynamics
- Electron and X-Ray Spectroscopy Techniques
- Dental Research and COVID-19
- Adrenal and Paraganglionic Tumors
- Lattice Boltzmann Simulation Studies
- Electron Spin Resonance Studies
- Anatomy and Medical Technology
- Chalcogenide Semiconductor Thin Films
- Digital Radiography and Breast Imaging
European X-Ray Free-Electron Laser
2020-2025
Diamond Light Source
2015-2016
Elettra-Sincrotrone Trieste S.C.p.A.
2013-2015
Deutsches Elektronen-Synchrotron DESY
2015
University of Siegen
2008
The idea of using ultrashort X-ray pulses to obtain images single proteins frozen in time has fascinated and inspired many. It was one the arguments for building free-electron lasers. According theory, extremely intense provide sufficient signal dispense with crystals as an amplifier, pulse duration permits capturing diffraction data before sample inevitably explodes. This first demonstrated on biological samples a decade ago giant mimivirus. Since then, large collaboration been pushing...
Abstract A comprehensive insight into ultrafast dynamics of photo-switchable materials is desired for efficient control material properties through light excitation. Here, we study a polycrystalline spin crossover thin film as prototypical example and reveal the sequential photo-switching dynamics, from local molecular rearrangement to global lattice deformation. On earliest femtosecond timescale, structural occurs within constant unit-cell volume two-step process, involving initial...
New synthetic hybrid materials and their increasing complexity have placed growing demands on crystal growth for single-crystal X-ray diffraction analysis. Unfortunately, not all chemical systems are conducive to the isolation of single crystals traditional characterization. Here, small-molecule serial femtosecond crystallography (smSFX) at atomic resolution (0.833 Å) is employed characterize microcrystalline silver n-alkanethiolates with various alkyl chain lengths free electron laser...
Due to its extremely short timescale, the non-equilibrium melting of metals is exceptionally difficult probe experimentally. The knowledge mechanisms thus based mainly on results theoretical predictions. This work reports investigation ultrafast thin polycrystalline Pd films studied by optical laser pump – X-ray free-electron experiments and molecular-dynamics simulations. By acquiring diffraction snapshots with sub-picosecond resolution, we capture sample's atomic structure during...
With the increased brilliance of state-of-the-art Synchrotron radiation sources and advent Free Electron Lasers enabling revolutionary science with EUV to X-ray photons comes an urgent need for suitable photon imaging detectors. Requirements include high frame rates, very large dynamic range, single-photon counting capability low probability false positives, (multi)-megapixels.
With the increased brilliance of state-of-the-art Synchrotron radiation sources and advent Free Electron Lasers enabling revolutionary science on atomic length time scales with EUV to X-ray photons comes an urgent need for suitable photon imaging detectors. Requirements include high frame rates, very large dynamic range, single-photon counting capability low probability false positives, (multi)-megapixels.
The European X-ray Free Electron Laser is a research facility located close to Hamburg, offering pulses with ultra-high brilliance and femtosecond duration at megahertz repetition rates. detection systems necessary unlock the full scientific potential made possible by this machine poses considerable challenges both in terms of data volume rate, as well interpretation their recorded signal. To provide optimal quality, expert detector-specific knowledge not easily accessible external users...
The diagnostics of X-ray beam properties has a critical importance at the European Free-Electron Laser facility. Besides existing diagnostic components, utilization diamond sensor was proposed to achieve radiation-hard, non-invasive position and pulse energy measurements for hard X-rays. In particular, with very X-rays, diamond-based sensors become useful complement gas-based devices which lose sensitivity due significantly reduced gas cross-sections. presented in this work were performed...
Over the last decade, synchrotron radiation sources have seen a significant increase in brilliance, and advent of free electron lasers has made entire new research fields accessible to investigations with X-rays. These advances light source capabilities resulted not only host scientific discoveries, but also need for generation X-ray imaging detectors that can match sources' terms frame rate image dynamic range while recording information fine granularity over large – preferably...
The X-ray free-electron lasers that became available during the last decade, like European XFEL (EuXFEL), place high demands on their instrumentation. Especially at low photon energies below 1 keV, detectors with sensitivity, and consequently noise quantum efficiency, are required to enable facility users fully exploit scientific potential of source. A 1-Megapixel pnCCD detector a 1024 × pixel format has been installed commissioned for imaging applications Nano-Sized Quantum System (NQS)...
Superfluid helium nanodroplets are an ideal environment for the formation of metastable, self-organized dopant nanostructures. However, presence vortices often hinders their formation. Here, we demonstrate generation vortex-free and explore size range in which they can be produced. From x-ray diffraction images xenon-doped droplets, identify that single compact structures, assigned to aggregation, prevail up 10^{8} atoms per droplet. This finding builds basis exploring assembly...
Abstract The idea of using ultrashort X-ray pulses to obtain images single proteins frozen in time has fascinated and inspired many. It was one the arguments for building free-electron lasers. According theory 1 , extremely intense provide sufficient signal dispense with crystals as an amplifier, pulse duration permits capturing diffraction data before sample inevitably explodes 2 . This first demonstrated on biological samples a decade ago giant mimivirus 3 Since then large collaboration 4...
X-ray Free Electron Lasers (XFELs) allow the collection of high-quality serial femtosecond crystallography data. The next generation megahertz superconducting FELs promises to drastically reduce data times, enabling capture more structures with higher signal-to-noise ratios and facilitating complex experiments. Currently, gas dynamic virtual nozzles (GDVNs) stand as sole delivery method capable best utilizing repetition rate sources for crystallography. However, their substantial sample...
With the increased brilliance of state-of-the-art synchrotron radiation sources and advent free-electron lasers (FELs) enabling revolutionary science with EUV to X-ray photons comes an urgent need for suitable photon imaging detectors. Requirements include high frame rates, very large dynamic range, single-photon sensitivity low probability false positives (multi)-megapixels. At DESY, one ongoing development project - in collaboration RAL/STFC, Elettra Sincrotrone Trieste, Diamond, Pohang...
PERCIVAL ("Pixelated Energy Resolving CMOS Imager, Versatile And Large") is a monolithic active pixel sensor (MAPS) based on technology. Is being developed by DESY, RAL/STFC, Elettra, DLS, and PAL to address the various requirements of detectors at synchrotron radiation sources Free Electron Lasers (FELs) in soft X-ray regime. These include high frame rates FELs base-rate compatibility, large dynamic range, single-photon counting capability with low probability false positives, quantum...
Abstract We present the development of a gain correction process for Large Pixel Detector (LPD) developed by Science and Technology Facilities Council (STFC) Femtosecond X-Ray Experiment (FXE) instrument based at European X-ray Free Electron Laser (EuXFEL). LPD operates 4.5 MHz as necessitated EuXFEL's pulse timing structure has large dynamic range capturing maximum 10 5 photons/pixel @ 12 keV. Experiments FXE require highly accurate measurements relative changes in scattering intensity on...
Free-Electron Lasers and Synchrotrons are rapidly increasing in brilliance. This has led a requirement of large dynamic range high frame rate sensors that is now being fulfilled by the PERCVIAL CMOS imager for direct X-ray detection developed at Rutherford Appleton Laboratory. Utilising lateral overflow pixel back-side illumination, PERCIVAL simultaneously achieves low-noise single-photon full well up to 107 e−, all while maintaining 120Hz. currently test structure stage, will be produced 2...
X-ray free-electron lasers (XFEL) provide unique opportunities for hard emission spectroscopy (XES) in solution phase by enabling femtosecond temporal resolution. The high brilliance and MHz repetition rate of such sources drive the development specialized sample delivery systems to overcome challenges degradation, as well major advances multiple-gain detectors fully utilize dynamic range required detection. This paper addresses experimental limitations that arise a typical XES experiment...
The PERCIVAL soft-X-ray (250 eV 1 keV) image detector project is a collaboration between DESY, STFC, Elettra Sincrotrone Trieste and Diamond Light Source. objective of the to develop back-thinned CMOS which outperforms present soft-X ray technology, in terms sensor size, noise, dynamic range frame rate. size this 13M pixel imager associated with its 120 frames per second rate impose very challenging requirements Data Acquisition Backend system. A DAQ backend system architecture, using...
Demand for time resolved experiments, of which the information related to detected events is an essential requirement, rapidly increasing in synchrotron research experiments. Timepix3 a read-out chip pixelated detectors that places stamp every event with nominal resolution 1.5625 ns and provides measure energy same by Time over Threshold technique. can then be promising readout A prototype system, based on modified version MERLIN has already been developed detector group Diamond Light Source...
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