Neonatal brain damage Abstract A specialized neurogenic niche along the ventricles accumulates millions of progenitor cells in the developing brain.
Such x-ray sources are used in diverse pump-probe experiments and also have prospective biomedical imaging applications. The operational regime of such sources can be extended into the ultrafast fs range with a tabletop setup, with few-cycle driving lasers and suitable target selection. In this talk I will discuss the physical processes in the generation of hard x-rays in such sources. Experiments were conducted on an ultrashort pulse, 1 kHz repetition-rate laser using solid targets at the CLPU laser facility in Salamanca, Spain.
The obtained experimental results were used for benchmarking the simulation. Dátum: Előadás címe: Scattering of ultrashort electromagnetic pulses on a system of two parallel current sheets: the role of the radiation reaction and of the time delay Előadó: Mónika Polner Absztrakt: The reflection and transmission of a few-cycle laser pulse impinging on two parallel thin metal layers have been analyzed. Our model is an extension of the one-layer scattering problem described in , and the analysis is based on classical electrodynamics and mechanics.
The two layers, with thickness much smaller than the skin depth of the radiation field, are represented by current sheets, which are embedded in three dielectrics, all with different index of refraction. The dynamics of the surface currents and the complete radiation field are described by the coupled system of Maxwell-Lorentz equations.
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In our analysis particular attention has been paid to the role of the radiation reaction and of the time delay.
There are several sources of time delay in the extended system: due to the angle of incidence of the impinging laser pulse and due to the propagation time between the two surface current sheets.
In this presentation we show the analytic solution of the resulting coupled delay differential-difference system of equations when the three dielectrics have the same index of refraction, besides, we show some numerical studies of the most general case.
The main emphasis is on the effect of the delay on the dynamics of the system. Előadás címe: Beam transport and monitoring of laser-driven particle beams Előadó: Jörg Pawelke OncoRay — National Center for Radiation Research in Oncology, Dresden, Germany; Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden; and Helmholtz-Zentrum Dresden-Rossendorf Absztrakt: Particle acceleration by high intensity lasers promises more compact and cost effective ion sources as well as electron beams of very high energy for radiotherapy application.
In contrast to pencil-like, monoenergetic, and quasi continuous beams from conventional accelerators, laser-driven beams are characterized by short pulses of very high particle flux, low repetition rate, broad energy spectrum, large divergence and significant pulse-to-pulse fluctuation.
In consequence, a future medical application requires not only a high power laser system and laser target to generate particle beams of therapeutic quality but also new technical solutions for suitable beam detection and dosimetry, beam transport, dose delivery including treatment planning along with research on the radiobiological consequences of short radiation pulses with prostate volume normal range radiology pulse dose rate.
The status of the ongoing joint translational research project onCOOPtics of several institutions in Germany will be presented with an emphasis on beam detection and beam transport via pulsed magnets.
Előadás címe: Short Wavelength Radiation in Laser-Plasma Interactions Előadó: Zsolt Lécz Absztrakt: Interaction of relativistically intense laser pulses with matter involves highly nonlinear processes and produces energetic charged particles and photons with unique properties.
Numerous mechanisms have been identified for ion acceleration or for high harmonic acceleration, but their efficiency is usually very low. Our primary goal is to increase the energy conversion efficiency from laser pulse into higher harmonics.
The synchrotron radiation emitted by relativistic electrons oscillating in magnetic undulators is a powerful source of short wavelength X-ray radiation.
Electrons oscillate at the laser-plasma interface as well, where they have complicated trajectory and can emit synchrotron-like coherent or incoherent radiation, depending on the plasma density and surface structure. In this work we investigate such interactions with solid density cylindrical targets or flat foils equipped with nanorods or microdots on their surfaces. Előadás címe: Towards ultrafast, nanoscale optical switching Előadó: Péter Dombi Absztrakt: Nano-optical near fields, generated, for example, by plasmon oscillations have several unique properties.
Hundred-times electric field enhancement and few-nanometer field localization of a laser pulse can be easily achieved. If we induce plasmon oscillations with ultrashort pulses, high spatiotemporal localization and highly nonlinear interactions are possible. Both are prerequisites for ultrafast, nano-integrated optical devices. As first steps in this direction, I will show new methods to characterize nano-optical near fields with nanometer resolution and ways to generate nonlinear interactions with low-energy laser pulses.
Ultrafast laser spectroscopy has been long the tool for examining mechanistic aspects of light induced processes in semiconductors as well as at semiconductor interfaces. So far, most of the work has focused mainly on transient absorption spectroscopy, at relatively long timescales typically ns-ms, sometimes pswhere charge transfer, recombination, and different surface reactions occur.
On the other hand, much less is known about the photo-excitation process itself, carrier cooling and trapping, which occurs at the femtosecond timescale. We aim to understand the peculiar conduction mechanisms including photoinduced charge carrier formation, exciton dissociation, recombination, etc. While these materials play an impressively increasing role in different practical applications, very little is known about the fundamentals of the mechanism of photo conductivity which forms the basis of most applications observed in these materials.
In this talk I will first present the background of the research and some of the previous achievements of the PI. Subsequently, I will prostate volume normal range radiology the state-of-the-art how ultrafast laser pulses can be employed as tools to characterize the above listed phenomena in different nanomaterials.
Finally, I will highlight some of our future plans. Előadás címe: Probing the structure and dynamics of nanomaterials and molecules Előadó: Mousumi Upadhyay-Kahaly Absztrakt: Modern technology entails the manipulation of matter on ultrashort scales, and measurement of the dynamic processes in ultrafast domain.
Thus "ultrafast science" impacts multiple areas of modern physics, chemistry, biology, materials science, engineering etc. Formation and breaking of chemical bonds occur in femtosecond time scale, and thus, elementary molecular processes can be observed and utilised by freezing the transition states of chemical processes at ultrashort time scale, even shorter than the vibrational and rotational periods in matter.
Along with the technological advances, ultrafast lasers, such as in ELI-ALPS, are employed to probe the molecular systems, to understand their time evolution and, to investigate intricate details of the time-resolved behavior of matter.
However limitations in controlling the experimental parameters and data processing requires theoretical tools to support and complement while probing the evolution of the electronic structures post controlled excitation in the time domain.
In the presentation, we will discuss structure-function relationships in materials using first principles quantum mechanical calculations based on Hűtés és prosztatitis functional theory and time dependent density functional theory, touching upon different aspects of novel material synthesis, energetics, lower dimensional systems, organometallic substances etc.
Unlike previous methods based on making a deep in the spectral amplitude of the seed prostate volume normal range radiology, here the achievable bandwidth is considerably broader along with a lossless overall amplification process. It was also shown that an additional polarization rotation takes place during the pulse amplification and we Duzzanat a prosztatitis to mitigate it with thicker decoding quartz so as to ensure good efficiency, which has been experimentally proved.
Because the PE amplifier usually introduces dip in the spectrum, an additional conventional Ti:Sa amplifier was built to smooth the spectrum and also promote the energy. The compressibility of the amplified pulse after the PE amplifier has also been verified by experiment. According to the simulations, the high energy polarization encoded Ti:Sa amplifiers predicts an amplification bandwidth of nm, making it a promising technique for intermediate and final amplifiers of high field Ti:Sa CPA-laser systems.
In our research we have suggested to add to EDP Ti:Sa combination the third element, namely Thin Disk crystal geometry EDP-TD to overcome the limitations associated with thermal cooling of crystal and transverse amplified spontaneous emission in high average power laser systems based on Ti:Sa amplifiers. In this talk we will discuss the possible benefits of this idea, as well as the results ofproof-of-principal experiments where first time, according to our knowledge, the scheme of EDP-TD was tested.
Előadás címe: Optimization and simulation for the development of advantageous plasmonic structures Előadó: Tibor Csendes, Balázs Bánhelyi, and Mária Csete University of Szeged Absztrakt: New techniques will be introduced to design tiny optical sensors applying the Matlab based COMSOL simulation program and cleverly formulated constrained nonlinear optimization problems.
In this way we could find good solutions that are favorable also with respect topractical realization. We illustrate prostate volume normal range radiology methodology on some reallife examples. Details of the technique will be highlighted also regarding the limitations, the huge computational complexity, and the evaluation of the results obtained.
Előadás címe: Ionisation induced electron trapping in the linear regime of a laser wakefield accelerator Előadó: Christos Kamperidis Absztrakt: The scheme of Laser Wakefield electron acceleration LWFA has rapidly matured over the past decade, from proof-of-principle experiments to real life applications, such as non-destructive X-ray imaging.
In this seminar, we will describe the basic principles of LWFA, show how ionisation injection Antibiotikus ital a prosztatitisből the laser requirements to achieve stable relativistic electron beams and outline the potential of these ultra-compact relativistic accelerators.
Előadás címe: Gravitational waves: prediction, discovery, prospects Előadó: László Árpád Gergely Absztrakt: years ago the concept of Newtonian gravitational force was replaced by space-time curvature. Matter tells space-time how to curve and space-time tells matter how to move. These effects however are not instantaneous.
Gravity propagates with the speed of light.
- Я полагаю, что твоя теория объясняет все известные нам факты, - осторожно сказал Хилвар.
- Mi a rosszabb prosztatitis
The propagating curvature modulations on the background curvature are the gravitational waves. They are easily produced in the regions of the universe, where the energetics is violent, for example, when black holes collide. Such gravitational waves produced 1. During their travel through the Universe, the waves weakened such that they produced a deformation of one part of prostate volume normal range radiology thousand of the size of the proton, hence the detection by laser interferometry has been an engineering success.
The Advanced LIGO detectors will undergo further improvements, and other similar detectors are on the verge of completion. New types of gravitational wave detectors, either space-born prostate volume normal range radiology based on radio interferometry are also envisaged.
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The era of gravitational wave astronomy has begun, a new window to the Universe has opened. Előadás címe: Reaction microscope and data analysis with GO4 Előadó: Miklós Füle Absztrakt: Understanding of the three dimension structure, photochemical dynamics and fragmentation of molecules has improved substantially by variety of spectroscopic method.
One of those techniques is the photoelectron spectroscopy in which the high energy photon absorbed by the molecule and an electron ejected subsequently from the atomic system. Based on the new technology development in the last two decades concerning the ultrafast laser technology and time-resolved spectroscopic technology and also the single-particle imagingtechnology a new powerful spectroscopic imaging method has emerged.
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The tuneable, fully coherent pulses of FERMI open up opportunities for exploring transient electron dynamics and controlling electronic wave packets during a photoionization process in gases. During the seminar, I would like to introduce the Low Density Matter end station at FERMI, the operation of its angularly resolved photoelectron spectrometer during experimental runs, and the methods for data collection, processing and interpretation.
Fibrózis prosztata Longidasa címe: An overview of attosecond prostate volume normal range radiology generation Előadó: Fatemeh Aeenehvand Absztrakt: The first part of this talk is focused on theoretical analysis of high-harmonic generation in solids and comparison with gas. The effects of strength field intensity is considered, the results show a simple approximate cutoff law for HHG in solids.
ABHD4-dependent developmental anoikis safeguards the embryonic brain | Nature Communications
The HHG process using the saddle point approximation is also investigated. Concerning the characterization of the probe pulses, the temporal duration and the carrier-envelope phase CEP stability is investigated, finally, the measurement of charge migration in the amino acid Phenylalanine is demonstrated, and it shows that attosecond science offers the possibility to elucidated process ultimately leading to charge localization in complex molecule. Attosecond science holds the promise to observe and to control the motion of electrons on their natural time scale.
It is now possible to take snapshots of electrons in motion in atoms, molecules, and solids.
The long-lasting dream of chemists and physicists to watch and to control in real time the formation and breaking of chemical bonds or electrons leaving an atom is now closer to realization than ever.
These experimental advances pose considerable challenges for theory. Time-resolved photoemission experiments employing attosecond streaking of electrons emitted by an extended ultraviolet pump pulse and probed by a few-cycle near-infrared pulse found a time delay of about as between photoelectrons from the conduction band and those from the 4f core level of tungsten.
We present a microscopic simulation of the emission time and energy spectra employing a classical transport theory.
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Our calculations reproduced well both the emission spectra and streaking images. We found delay times near the lower bound of the experimental data.
Photoemission spectra feature also complex correlation satellite structures signifying the simultaneous excitation of single or multiple plasmons. The time delay of the plasmon satellites relative to the main line can be resolved in attosecond streaking experiments.
Time-resolved photoemission thus provides the key to discriminate between intrinsic and extrinsic plasmon excitation. We demonstrate the determination of the branching ratio between intrinsic and extrinsic plasmon generation for simple metals. Előadás címe: XUV induced ultrafast mechanisms in molecular structures: from attosecond physics … to astrochemistry Előadó: dr. Franck Lépine Absztrakt: Short XUV pulses combine 2 advantages for physicists and chemists, which are motivating the development of intense research programs worldwide.
Society of Hungarian Radiologists
First, high-energy photons allow the generation of highly excited species and second, short duration gives access to ultrafast phenomena in realtime. In molecules, short XUV pulses can trigger complex dynamics that can be followed in real-time using pump-probe schemes, down to the attosecond time-scale. Due to high prostate volume normal range radiology energy excitation, induced processes imply interaction between all the particles constituting the molecule so-called: electron correlation, non-adiabatic couplings etc….
Therefore a theoretical description requires state-of-the-art many-body quantum theories. Although challenging, it is expected that this research activity would have major impact in other fields and would nourish analytical chemistry, molecular electronics, astrophysics and fundamental aspects of quantum mechanics in general. In this talk, I will present the research program developed in my group to extend XUV induced molecular science to the investigation of increasingly large molecular systems.
The root of this problem can be tracked back to the very definition of these long-range interacting theories such as QED. The IR catastrophe and its resolution by cancelling these divergences will be also discussed. The Bloch-Nordsieck model provides the IR limit of QED and in its framework all the radiative corrections to the electron propagator can be fully summed.
However, perturbation theory does not provide the right tool for this operation: the exact Dyson-Schwinger DS equation needed to be solved with the aid of the Ward-Takahashi identities. Solving the DS equation at finite temperatures is prostate volume normal range radiology possible and will be presented in the talk.
Előadás címe: Report on development of an all reflective polarization rotator and an Yb:CaF2 thin disk amplifier Előadó: János Bohus Absztrakt: We present a conceptual design of an RDPR Reflective device for polarization rotation as a preferable alternative to conventionally used HWPs halfwave plates. Furthermore, the spectral transfer function is widely selectable, due to the purely reflective design.
Moreover, the device is scalable in size and the damage threshold is only limited by the mirrors, which is considerably higher than for HWPs. Additionally, in comparison to those, RDPRs create no prepulses leading to postpulses generated in the subsequent high-power short-pulse laser chain. Hence, RDPRs are also suitable for the manipulation of the polarization of compressed, and therefore ultra-short laser pulses.
Furthermore we report on development of a thin disk energetic amplifier prostate volume normal range radiology on Yb:CaF2. Results of gain, thermal lensing, depolarisation loss, temperature distribution measurements carried out at Institute of Optic in Paris are presented.
The laser setup operated at an intensity of 1× Wcm During the campaign, a liquid target setup suitable for kHz repetition-rate applications were investigated. A solid copper target on a high-speed target stage was also installed to test x-ray diagnostics, and the installed delay scheme to provide a controlled laser pre-pulse.