Download or read book X ray Thomson Scattering from Dense Plasmas written by and published by . This book was released on 2007 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Regime of Thomson Scattering Probing Dense Plasmas with X Ray Lasers written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper the authors demonstrate through calculations and theoretical analysis the first application of a x-ray laser for probing hot, high-density plasmas (n[sub e][ge] 10[sup 23] cm[sup -3]) using a Ni-like transient collisional excitation x-ray laser as a probe. Theoretical predictions are used to diagnose the electron temperature in short pulse (500 fs) laser produced plasmas. The threshold power of the x-ray probe is estimated by comparing theoretical scattering levels with plasma thermal emission. The necessary spectral resolution of the instrument sufficient for resolving electron temperature is given.
Download or read book Warm Dense Plasma Characterization by X ray Thomson Scattering written by and published by . This book was released on 2000 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: We describe how the powerful technique of spectrally resolved Thomson scattering can be extended to the x-ray regime, for direct measurements of the ionization state, density, temperature, and the microscopic behavior of dense cool plasmas. Such a direct measurement of microscopic parameters of solid density plasmas could eventually be used to properly interpret laboratory measurements of material properties such as thermal and electrical conductivity, EUS and opacity. In addition, x-ray Thomson scattering will provide new information on the characteristics of rarely and hitherto difficult to diagnose Fermi degenerate and strongly coupled plasmas.
Download or read book Theoretical Model and Interpretation of Dense Plasma X Ray Thomson Scattering written by and published by . This book was released on 2002 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present analytical expressions for the dynamic structure factor, or form factor S(k, [omega]), which is the quantity describing the inelastic x-ray cross section from a dense plasma or a simple liquid. The results, based on the random phase approximation (RPA) for the treatment on the charged particle coupling, can be applied to describe scattering from either weakly coupled classical plasmas or degenerate electron liquids. The form factor correctly reproduces the Compton energy downshift and the usual Fermi-Dirac electron velocity distribution for S(k, [omega]) in the case of a cold degenerate plasma. the usual concept of scattering parameter is also reinterpreted for the degenerate case in order to include the effect of the Thomas-Fermi screening. The results shown in this work can be applied to interpreting x-ray scattering in warm dense plasmas occurring in inertial confinement fusion experiments or inside the interior of planets.
Download or read book K alpha X ray Thomson Scattering From Dense Plasmas written by and published by . This book was released on 2009 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spectrally resolved Thomson scattering using ultra-fast K-[alpha] x-rays has measured the compression and heating of shocked compressed matter. The evolution and coalescence of two shock waves traveling through a solid density LiH target were characterized by the elastic scattering component. The density and temperature at shock coalescence, 2.2 eV and 1.7 x 1023cm−3, were determined from the plasmon frequency shift and the relative intensity of the elastic and inelastic scattering features in the collective scattering regime. The observation of plasmon scattering at coalescence indicates a transition to the dense metallic state in LiH. The density and temperature regimes accessed in these experiments are relevant for inertial confinement fusion experiments and for the study of planetary formation.
Download or read book Ion Structure for X ray Thomson Scattering in Dense Fusion Plasmas written by K Wünsch and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dense Matter Characterization by X ray Thomson Scattering written by and published by . This book was released on 2000 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: We discuss the extension of the powerful technique of Thomson scattering to the x-ray regime for providing an independent measure of plasma parameters for dense plasmas. By spectrally-resolving the scattering, the coherent (Rayleigh) unshifted scattering component can be separated from the incoherent Thomson component, which is both Compton and Doppler shifted. The free electron density and temperature can then be inferred from the spectral shape of the high frequency Thomson scattering component. In addition, as the plasma temperature is decreased, the electron velocity distribution as measured by incoherent Thomson scattering will make a transition from the traditional Gaussian Boltzmann distribution to a density-dependent parabolic Fermi distribution to. We also present a discussion for a proof-of-principle experiment appropriate for a high energy laser facility.
Download or read book Using X ray Thomson Scattering to Measure Plasma Conditions in Warm Dense Matter Experiments on the OMEGA Laser written by Alison Marie-Anne Saunders and published by . This book was released on 2018 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: High energy density physics (HEDP) is an emerging field that seeks to investigate the properties of matter at extreme conditions. High energy density conditions occur in materials with pressures exceeding 1 Mbar, or pressures that exceed Earth’s atmospheric pressure by a factor of more than a million. A regime of HEDP of particular interest is warm dense matter (WDM) physics, which describes the behavior of materials at near solid densities and 10’s of eV temperatures. WDM occurs in astrophysical objects, such as giant planets and brown dwarfs, and is also generated in inertial confinement fusion (ICF) experiments. X-ray Thomson scattering (XRTS) offers a powerful tool to probe the equation of state of WDM. XRTS spectra consist of two components: elastically scattered photons with the frequency of the original x-ray source and inelastically scattered photons that are down- shifted in frequency. The Compton-shifted profile of inelastically scattered x-rays can be analyzed to return the sample’s electron density and electron temperature. The ratio of elastically to inelastically scattered x-rays relates to the number of tightly bound versus free electrons, and thus reflects the ionization state. This thesis discusses the results of XRTS experiments on WDM performed at the OMEGA Laser facility. The first experiment presents and discusses XRTS results from 1 mm diamond spheres. The scattering spectra show evidence of higher ionization than predicted by several commonly-applied ionization models. A second experiment analyzed the contributions to elastic scattering from a small argon impurity in imploding beryllium capsules. The exper- iment found that less than 1 at.% of argon significantly affects the elastic scattering signal strength, and concluded that impurities in a sample should be considered before drawing conclusions from elastic scattering signals. The final experiment uses XRTS to measure the electron temperature and ionization state in isochorically heated materials used in ion stopping power experiments. The results from these experiments demonstrate the power of XRTS to measure ionization in WDM to benchmark theoretical modeling.
Download or read book Using Collective X ray Thomson Scattering to Measure Temperature and Density of Warm Dense Matter written by and published by . This book was released on 2009 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collective x-ray Thomson scattering allows measuring plasmons, i.e electron plasma oscillations (Langmuir waves). This is manifest in the appearance of spectrally up- and down-shifted spectral features in addition to the Rayleigh signal. The ratio of the up- and down-shifted signals is directly related to detailed balance, allowing to determine the plasma temperature from first principles. The spectral shift of the plasmon signals is sensitive to temperature and electron density. We discuss the experimental considerations that have to be fulfilled to observe plasmon signals with x-ray Thomson scattering. As an example, we describe an experiment that used the Cl Ly-[alpha] x-ray line at 2.96 keV to measure collective Thomson scattering from solid beryllium, isochorically heated to 18 eV. Since temperature measurement based on detailed balance is based on first principles, this method is important to validate models that, for example, calculate the static ion-ion structure factor S{sub ii}(k).
Download or read book Thomson Scattering from Near solid Density Plasmas Using Soft X ray Free Electron Lasers written by and published by . This book was released on 2006 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: We propose a collective Thomson scattering experiment at the VUV free electron laser facility at DESY (FLASH) which aims to diagnose warm dense matter at near-solid density. The plasma region of interest marks the transition from an ideal plasma to a correlated and degenerate many-particle system and is of current interest, e.g. in ICF experiments or laboratory astrophysics. Plasma diagnostic of such plasmas is a longstanding issue. The collective electron plasma mode (plasmon) is revealed in a pump-probe scattering experiment using the high-brilliant radiation to probe the plasma. The distinctive scattering features allow to infer basic plasma properties. For plasmas in thermal equilibrium the electron density and temperature is determined from scattering off the plasmon mode.
Download or read book X ray Thomson Scattering for Measuring Dense Beryllium Plasma Collisionality written by and published by . This book was released on 2009 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: We are developing a target platform that utilizes short-pulse (10 ps) generated hot electrons (≈1 MeV) to isochorically heat solid density beryllium up to several 10 eV. X-ray Thomson scattering is employed to characterize the plasma conditions. X-rays from a Cl Ly-[alpha] line source at 2.96 keV are scattered off the plasma in forward direction where the inelastically scattered signal is sensitive to plasma oscillations. Besides Landau-damping the strong energy down-shifted plasmon signal is also broadened by collisions which, in turn, allows to infer the collision rate and thus the conductivity in these plasmas. Recently, we demonstrated that from the ratio of the energy up-shifted to the down-shifted plasmon signals the plasma temperature can be inferred from the detailed balance relation which is based on first principles. Thus from the Plasmon shift and detailed balance we will be able to consistently determine plasma density and temperature, and relate this to the collisionality inferred from the Plasmon broadening. A precise knowledge of the collisionality in the parameter regime we are aiming at with these experiments is important to correctly model the conditions encountered during capsule implosions at the National Ignition Facility.
Download or read book Soft X Ray Thomson Scattering in Warm Dense Hydrogen at FLASH written by and published by . This book was released on 2009 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present collective Thomson scattering with soft x-ray free electron laser radiation as a method to track the evolution of warm dense matter plasmas with ≈200 fs time resolution. In a pump-probe scheme an 800 nm laser heats a 20 [mu]m hydrogen droplet to the plasma state. After a variable time delay in the order of ps the plasma is probed by an x-ray ultra violet (XUV) pulse which scatters from the target and is recorded spectrally. Alternatively, in a self-Thomson scattering experiment, a single XUV pulse heats the target while a portion of its photons are being scattered probing the target. From such inelastic x-ray scattering spectra free electron temperature and density can be inferred giving insight on relaxation time scales in plasmas as well as the equation of state. We prove the feasibility of this method in the XUV range utilizing the free electron laser facility in Hamburg, FLASH. We recorded Thomson scattering spectra for hydrogen plasma, both in the self-scattering and in the pump-probe mode using optical laser heating.
Download or read book Demonstration of Successful X ray Thomson Scattering Using Picosecond K alpha X ray Sources for the Characterization of Dense Heated Matter written by and published by . This book was released on 2008 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We discuss the first successful K-[alpha] x-ray Thomson scattering experiment from solid density plasmas for use as a diagnostic in determining the temperature, density, and ionization state of warm dense matter with picosecond resolution. The development of this source as a diagnostic and stringent requirements for successful K-[alpha] x-ray Thomson scattering are addressed. Data for the experimental techniques described in this paper [1] suggest the capability of single shot characterization of warm dense matter and the ability to use this scattering source at future Free Electron Lasers (FEL) where comparable scattering signal levels are predicted.
Download or read book Plasma Scattering of Electromagnetic Radiation written by John Sheffield and published by Academic Press. This book was released on 2010-11-25 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work presents one of the most powerful methods of plasma diagnosis in exquisite detail, to guide researchers in the theory and measurement techniques of light scattering in plasmas. Light scattering in plasmas is essential in the research and development of fusion energy, environmental solutions, and electronics.Referred to as the "Bible" by researchers, the work encompasses fusion and industrial applications essential in plasma research. It is the only comprehensive resource specific to the plasma scattering technique. It provides a wide-range of experimental examples and discussion of their principles with worked examples to assist researchers in applying the theory. - Computing techniques for solving basic equations helps researchers compare data to the actual experiment - New material on advances on the experimental side, such as the application of high density plasmas of inertial fusion - Worked out examples of the scattering technique for easier comprehension of theory
Download or read book Simulating X ray Thomson Scattering Signals from High density Millimetre scale Plasmas at the National Ignition Facility written by and published by . This book was released on 2014 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Statistical Physics of Dense Plasmas written by Setsuo Ichimaru and published by CRC Press. This book was released on 2019-01-07 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: This authoritative text offers a complete overview on the statistical mechanics and electrodynamics of physical processes in dense plasma systems. The author emphasizes laboratory-based experiments and astrophysical observations of plasma phenomena, elucidated through the fundamentals. The coverage encompasses relevant condensed matter physics, atomic physics, nuclear physics, and astrophysics, including such key topics as phase transitions, transport, optical and nuclear processes. This essential resource also addresses exciting, cutting edge topics in the field, including metallic hydrogen, stellar and planetary magnetisms, pycnonuclear reactions, and gravitational waves. Scientists, researchers, and students in plasma physics, condensed matter physics, materials science, atomic physics, nuclear physics, and astrophysics will benefit from this work. Setsuo Ichimaru is a distinguished professor at the University of Tokyo, and has been a visiting member at The Institute for Advanced Study in Princeton, New Jersey, at the University of California, San Diego (UCSD), the Institute for Theoretical Physics at Johannes Kepler University, and the Max Planck Institute for Quantum Optics. He is a recipient of the Subramanyan Chandrasekhar Prize of Plasma Physics from the Association of Asia-Pacific Physical Societies and the Humboldt Research Award from the Alexander von Humboldt Foundation.
