Optics is the branch of physics which involves the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behavior of visible, ultraviolet, and infrared light. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties.
A synchrotron light source is a source of electromagnetic radiation (EM) usually produced by a storage ring, for scientific and technical purposes. First observed in synchrotrons, synchrotron light is now produced by storage rings and other specialized particle accelerators, typically accelerating electrons. Once the high-energy electron beam has been generated, it is directed into auxiliary components such as bending magnets and insertion devices in storage rings and free electron lasers. These supply the strong magnetic fields perpendicular to the beam that are needed to stimulate the high energy electrons to emit photons.
In accelerator physics, a beamline refers to the trajectory of the beam of particles, including the overall construction of the path segment along a specific path of an accelerator facility. This part is either
Biological small-angle scattering is a small-angle scattering method for structure analysis of biological materials. Small-angle scattering is used to study the structure of a variety of objects such as solutions of biological macromolecules, nanocomposites, alloys, and synthetic polymers. Small-angle X-ray scattering (SAXS) and small-angle neutron scattering (SANS) are the two complementary techniques known jointly as small-angle scattering (SAS). SAS is an analogous method to X-ray and neutron diffraction, wide angle X-ray scattering, as well as to static light scattering. In contrast to other X-ray and neutron scattering methods, SAS yields information on the sizes and shapes of both crystalline and non-crystalline particles. When used to study biological materials, which are very often in aqueous solution, the scattering pattern is orientation averaged.
Extended X-ray absorption fine structure (EXAFS), along with X-ray absorption near edge structure (XANES), is a subset of X-ray absorption spectroscopy (XAS). Like other absorption spectroscopies, XAS techniques follow Beer's law. The X-ray absorption coefficient of a material as a function of energy is obtained by directing X-rays of a narrow energy range at a sample, while recording the incident and transmitted x-ray intensity, as the incident x-ray energy is incremented.
The Stanford Synchrotron Radiation Lightsource, a division of SLAC National Accelerator Laboratory, is operated by Stanford University for the Department of Energy. SSRL is a National User Facility which provides synchrotron radiation, a name given to electromagnetic radiation in the x-ray, ultraviolet, visible and infrared realms produced by electrons circulating in a storage ring at nearly the speed of light. The extremely bright light that is produced can be used to investigate various forms of matter ranging from objects of atomic and molecular size to man-made materials with unusual properties. The obtained information and knowledge is of great value to society, with impact in areas such as the environment, future technologies, health, biology, basic research, and education.
The hard X-ray nanoprobe at the Center for Nanoscale Materials (CNM), Argonne National Lab advanced the state of the art by providing a hard X-ray microscopy beamline with the highest spatial resolution in the world. It provides for fluorescence, diffraction, and transmission imaging with hard X-rays at a spatial resolution of 30 nm or better. A dedicated source, beamline, and optics form the basis for these capabilities. This unique instrument is not only key to the specific research areas of the CNM; it will also be a general utility, available to the broader nanoscience community in studying nanomaterials and nanostructures, particularly for embedded structures.
High-energy X-rays or HEX-rays are very hard X-rays, with typical energies of 80–1000 keV (1 MeV), about one order of magnitude higher than conventional X-rays used for X-ray crystallography. They are produced at modern synchrotron radiation sources such as the Cornell High Energy Synchrotron Source, SPring-8, and the beamlines ID15 and BM18 at the European Synchrotron Radiation Facility (ESRF). The main benefit is the deep penetration into matter which makes them a probe for thick samples in physics and materials science and permits an in-air sample environment and operation. Scattering angles are small and diffraction directed forward allows for simple detector setups.
ALBA is a 3 GeV, third-generation synchrotron light source facility located in the Barcelona Synchrotron Park in Cerdanyola del Vallès near Barcelona, in Catalonia (Spain). It was constructed and is operated by CELLS, and co-financed by the Spanish central administration and regional Catalan Government.
The Australian Synchrotron is a 3 GeV national synchrotron radiation facility located in Clayton, in the south-eastern suburbs of Melbourne, Victoria. The facility opened in 2007, and is operated by the Australian Nuclear Science and Technology Organisation.
Modeling photon propagation with Monte Carlo methods is a flexible yet rigorous approach to simulate photon transport. In the method, local rules of photon transport are expressed as probability distributions which describe the step size of photon movement between sites of photon-matter interaction and the angles of deflection in a photon's trajectory when a scattering event occurs. This is equivalent to modeling photon transport analytically by the radiative transfer equation (RTE), which describes the motion of photons using a differential equation. However, closed-form solutions of the RTE are often not possible; for some geometries, the diffusion approximation can be used to simplify the RTE, although this, in turn, introduces many inaccuracies, especially near sources and boundaries. In contrast, Monte Carlo simulations can be made arbitrarily accurate by increasing the number of photons traced. For example, see the movie, where a Monte Carlo simulation of a pencil beam incident on a semi-infinite medium models both the initial ballistic photon flow and the later diffuse propagation.
Within physics, the Hybrid Theory for photon transport in tissue uses the advantages and eliminates the deficiencies of both the Monte Carlo method and the diffusion theory for photon transport to model photons traveling through tissue both accurately and efficiently.
McStas is free and open-source software simulator for neutron scattering experiments. McStas is an abbreviation for Monte carlo Simulation of triple axis spectrometers, but the software can be used to simulate all types of neutron scattering instruments. The software is based on both Monte Carlo methods and ray tracing. A special compiler translates a domain-specific language describing the neutron instrument geometry and component definitions to a stand-alone C code.
The Virtual Instrumentation Tool for the ESS (VITESS) is an open source software package for the simulation of neutron scattering experiments. The software is maintained and developed by the Forschungszentrum Jülich (FZJ), and available for Windows, Linux and Macintosh on the VITESS homepage. It is widely used for simulation of existing neutron scattering instruments as well as for the development of new instruments.
Atmospheric optics ray tracing codes - this article list codes for light scattering using ray-tracing technique to study atmospheric optics phenomena such as rainbows and halos. Such particles can be large raindrops or hexagonal ice crystals. Such codes are one of many approaches to calculations of light scattering by particles.
A charged particle accelerator is a complex machine that takes elementary charged particles and accelerates them to very high energies. Accelerator physics is a field of physics encompassing all the aspects required to design and operate the equipment and to understand the resulting dynamics of the charged particles. There are software packages associated with each domain. The 1990 edition of the Los Alamos Accelerator Code Group's compendium provides summaries of more than 200 codes. Certain codes are still in use today, although many are obsolete. Another index of existing and historical accelerator simulation codes is located at the CERN CARE/HHH website.
Optica is an optical design program used for the design and analysis of both imaging and illumination systems. It works by ray tracing the propagation of rays through an optical system. It performs polarization ray-tracing, non-sequential ray-tracing, energy calculations, and optimization of optical systems in three-dimensional space. It also performs symbolic modeling of optical systems, diffraction, interference, wave-front, and Gaussian beam propagation calculations. In addition to conducting simulations of optical designs, Optica is used by scientists to create illustrations of the simulated results in publications. Some examples of Optica being used in simulations and illustrations include holography, x-ray optics, spectrometers, Cerenkov radiation, microwave optics, nonlinear optics, scattering, camera design, extreme ultraviolet lithography simulations, telescope optics, laser design, ultrashort pulse lasers, eye models, solar concentrators and Ring Imaging CHerenkov (RICH) particle detectors.
Three-dimensional X-ray diffraction (3DXRD) is a microscopy technique using hard X-rays to investigate the internal structure of polycrystalline materials in three dimensions. For a given sample, 3DXRD returns the shape, juxtaposition, and orientation of the crystallites ("grains") it is made of. 3DXRD allows investigating micrometer- to millimetre-sized samples with resolution ranging from hundreds of nanometers to micrometers. Other techniques employing X-rays to investigate the internal structure of polycrystalline materials include X-ray diffraction contrast tomography (DCT) and high energy X-ray diffraction (HEDM).
Klaus-Dieter Liss, German: Liß, is a German-Australian physicist working in the field of experimental X-ray and neutron scattering and their applications. Liss research is on in-situ and real-time experiments with synchrotron and neutron radiation for the characterization of thermo-mechanical processes in metals; the investigation of phase transformations; the evolution of microstructures; and the kinetics of defects. His experimental achievements are the development of the Materials oscilloscope and the realization of the X-ray photon storage.
Muriel Thomasset, is a French physicist who specializes in optics. In 2003, she received an Irène Joliot-Curie Prize.
