Synchrotron radiation

About: Synchrotron radiation is a(n) research topic. Over the lifetime, 14639 publication(s) have been published within this topic receiving 244775 citation(s). The topic is also known as: magnetobremsstrahlung radiation & Synchrotron Radiation.

Radiative processes in astrophysics

Abstract: Chapter 1 Fundamentals of Radiative Transfer 1.1 The Electromagnetic Spectrum Elementary Properties of Radiation 1.2 Radiative Flux Macroscopic Description of the Propagation of Radiation Flux from an Isotropic Source-The Inverse Square Law 1.3 The Specific Intensity and Its Moments Definition of Specific Intensity or Brightness Net Flux and Momentum Flux Radiative Energy Density Radiation Pressure in an Enclosure Containing an Isotropic Radiation Field Constancy of Specific Intensity Along Rays in Free Space Proof of the Inverse Square Law for a Uniformly Bright Sphere 1.4 Radiative Transfer Emission Absorption The Radiative Transfer Equation Optical Depth and Source Function Mean Free Path Radiation Force 1.5 Thermal Radiation Blackbody Radiation Kirchhoff's Law for Thermal Emission Thermodynamics of Blackbody Radiation The Planck Spectrum Properties of the Planck Law Characteristic Temperatures Related to Planck Spectrum 1.6 The Einstein Coefficients Definition of Coefficients Relations between Einstein Coefficients Absorption and Emission Coefficients in Terms of Einstein Coefficients 1.7 Scattering Effects Random Walks Pure Scattering Combined Scattering and Absorption 1.8 Radiative Diffusion The Rosseland Approximation The Eddington Approximation Two-Stream Approximation Problems References Chapter 2 Basic Theory of Radiation Fields 2.1 Review of Maxwell's Equations 2.2 Plane Electromagnetic Waves 2.3 The Radiation Spectrum 2.4 Polarization and Stokes Parameters 62 Monochromatic Waves Quasi-monochromatic Waves 2.5 Electromagnetic Potentials 2.6 Applicability of Transfer Theory and the Geometrical Optics Limit Problems References Chapter 3 Radiation from Moving Charges 3.1 Retarded Potentials of Single Moving Charges: The Lienard-Wiechart Potentials 3.2 The Velocity and Radiation Fields 3.3 Radiation from Nonrelativistic Systems of Particles Larmor's Formula The Dipole Approximation The General Multipole Expansion 3.4 Thomson Scattering (Electron Scattering) 3.5 Radiation Reaction 3.6 Radiation from Harmonically Bound Particles Undriven Harmonically Bound Particles Driven Harmonically Bound Particles Problems Reference Chapter 4 Relativistic Covariance and Kinematics 4.1 Review of Lorentz Transformations 4.2 Four-Vectors 4.3 Tensor Analysis 4.4 Covariance of Electromagnetic Phenomena 4.5 A Physical Understanding of Field Transformations 129 4.6 Fields of a Uniformly Moving Charge 4.7 Relativistic Mechanics and the Lorentz Four-Force 4.8 Emission from Relativistic Particles Total Emission Angular Distribution of Emitted and Received Power 4.9 Invariant Phase Volumes and Specific Intensity Problems References Chapter 5 Bremsstrahlung 5.1 Emission from Single-Speed Electrons 5.2 Thermal Bremsstrahlung Emission 5.3 Thermal Bremsstrahlung (Free-Free) Absorption 5.4 Relativistic Bremsstrahlung Problems References Chapter 6 Synchrotron Radiation 6.1 Total Emitted Power 6.2 Spectrum of Synchrotron Radiation: A Qualitative Discussion 6.3 Spectral Index for Power-Law Electron Distribution 6.4 Spectrum and Polarization of Synchrotron Radiation: A Detailed Discussion 6.5 Polarization of Synchrotron Radiation 6.6 Transition from Cyclotron to Synchrotron Emission 6.7 Distinction between Received and Emitted Power 6.8 Synchrotron Self-Absorption 6.9 The Impossibility of a Synchrotron Maser in Vacuum Problems References Chapter 7 Compton Scattering 7.1 Cross Section and Energy Transfer for the Fundamental Process Scattering from Electrons at Rest Scattering from Electrons in Motion: Energy Transfer 7.2 Inverse Compton Power for Single Scattering 7.3 Inverse Compton Spectra for Single Scattering 7.4 Energy Transfer for Repeated Scatterings in a Finite, Thermal Medium: The Compton Y Parameter 7.5 Inverse Compton Spectra and Power for Repeated Scatterings by Relativistic Electrons of Small Optical Depth 7.6 Repeated Scatterings by Nonrelativistic Electrons: The Kompaneets Equation 7.7 Spectral Regimes for Repeated Scattering by Nonrelativistic Electrons Modified Blackbody Spectra y"1 Wien Spectra y"1 Unsaturated Comptonization with Soft Photon Input Problems References Chapter 8 Plasma Effects 8.1 Dispersion in Cold, Isotropic Plasma The Plasma Frequency Group and Phase Velocity and the Index of Refraction 8.2 Propagation Along a Magnetic Field Faraday Rotation 8.3 Plasma Effects in High-Energy Emission Processes Cherenkov Radiation Razin Effect Problems References Chapter 9 Atomic Structure 9.1 A Review of the Schrodinger Equation 9.2 One Electron in a Central Field Wave Functions Spin 9.3 Many-Electron Systems Statistics: The Pauli Principle Hartree-Fock Approximation: Configurations The Electrostatic Interaction LS Coupling and Terms 9.4 Perturbations, Level Splittings, and Term Diagrams Equivalent and Nonequivalent Electrons and Their Spectroscopic Terms Parity Spin-Orbit Coupling Zeeman Effect Role of the Nucleus Hyperfine Structure 9.5 Thermal Distribution of Energy Levels and Ionization Thermal Equilibrium: Boltzmann Population of Levels The Saha Equation Problems References Chapter 10 Radiative Transitions 10.1 Semi-Classical Theory of Radiative Transitions The Electromagnetic Hamiltonian The Transition Probability 10.2 The Dipole Approximation 10.3 Einstein Coefficients and Oscillator Strengths 10.4 Selection Rules 10.5 Transition Rates Bound-Bound Transitions for Hydrogen Bound-Free Transitions (Continuous Absorption) for Hydrogen Radiative Recombination - Milne Relations The Role of Coupling Schemes in the Determination of f Values 10.6 Line Broadening Mechanisms Doppler Broadening Natural Broadening Collisional Broadening Combined Doppler and Lorentz Profiles Problems References Chapter 11 Molecular Structure 11.1 The Born-Oppenheimer Approximation: An Order of Magnitude Estimate of Energy Levels 11.2 Electronic Binding of Nuclei The H2+ Ion The H2 Molecule 11.3 Pure Rotation Spectra Energy Levels Selection Rules and Emission Frequencies 11.4 Rotation-Vibration Spectra Energy Levels and the Morse Potential Selection Rules and Emission Frequencies 11.5 Electronic-Rotational-Vibrational Spectra Energy Levels Selection Rules and Emission Frequencies Problems References Solutions Index

GeV electron beams from a centimetre-scale accelerator

Abstract: Gigaelectron volt (GeV) electron accelerators are essential to synchrotron radiation facilities and free-electron lasers, and as modules for high-energy particle physics. Radiofrequency-based accelerators are limited to relatively low accelerating fields (10–50 MV m−1), requiring tens to hundreds of metres to reach the multi-GeV beam energies needed to drive radiation sources, and many kilometres to generate particle energies of interest to high-energy physics. Laser-wakefield accelerators1,2 produce electric fields of the order 10–100 GV m−1 enabling compact devices. Previously, the required laser intensity was not maintained over the distance needed to reach GeV energies, and hence acceleration was limited to the 100 MeV scale3,4,5. Contrary to predictions that petawatt-class lasers would be needed to reach GeV energies6,7, here we demonstrate production of a high-quality electron beam with 1 GeV energy by channelling a 40 TW peak-power laser pulse in a 3.3-cm-long gas-filled capillary discharge waveguide8,9.

Bremsstrahlung, Synchrotron Radiation, and Compton Scattering of High-Energy Electrons Traversing Dilute Gases

Abstract: Expressions are derived for the total energy loss and photon-production spectrum by the processes of Compton scattering, bremsstrahlung, and synchrotron radiation from highly relativistic electrons. For Compton scattering, the general case, the Thomson limit, and the extreme Klein-Nishina limit are considered. Bremsstrahlung is treated for the cases where the electron is scattered by a pure Coulomb field and by an atom. For the latter case the effects of shielding are discussed extensively. The synchrotron spectrum is derived for an electron moving in a circular orbit perpendicular to the magnetic field and also for the general case where the electron's motion is helical. The total photon-production spectrum is derived for each process when there is a power-law distribution of electron energies. The problems of the effects of the three processes on the electron distribution itself are considered. It is shown that if the electron loses a small fraction of its energy in a single occurrence of a process, the electron distribution function satisfies a continuity equation which is a differential equation in energy space. For the more general case where the electron can lose energy in discrete amounts (as in bremsstrahlung and extreme Klein-Nishina Compton losses), the electron distribution function satisfies an integro-differential equation. Some approximate solutions to this equation are derived for certain special cases.

On the possibilities of x-ray phase contrast microimaging by coherent high-energy synchrotron radiation

Abstract: Coherent properties of the x-ray beam delivered at the ESRF allow the observation of very weak perturbations of the wave front, resulting in the phase contrast. A straightforward experimental setup for phase contrast imaging is proposed and used to record holographic images from organic samples of 10-100 pm at energy lo-50 keV with the contrast up to 50%-100%. The theory of phase contrast imaging is considered and some theoretical estimations are made to reveal the performance of the proposed technique in terms of resolution, sensitivity, geometrical requirements, and ehergy range applicability. It is found that for carbon-based fibers a detectable size with 2% contrast is 0.1 ,um for 10 keV and - 1 pm for 100 keV, It is demonstrated that the fine interference structure of the image is very sensitive to the shape, density variation, and internal structure of the sample. Some prospects for the practical use and future development of the new coherent techniques such as phase contrast microscopy, microtomography, holography, and interferometry at high energies are also discussed. 0 I995 American Institute of Physics.