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Triple-axis Spectrometer
Triple-axis spectrometry (TAS, T also resolved as "three", S also resolved as "spectroscopy") is a technique used in inelastic neutron scattering. The instrument is referred to as triple-axis spectrometer (also called TAS). It allows measurement of the scattering function at any point in energy and momentum space physically accessible by the spectrometer. History {{expand section, date=February 2019 The triple-axis spectrometry method was first developed by Bertram Brockhouse at the National Research Experimental NRX reactor at the Chalk River Laboratories in Canada. The first results from the prototype triple-axis spectrometer were published in January 1955 and the first true triple-axis spectrometer was built in 1956. Bertram Brockhouse shared the 1994 Nobel prize for Physics for this development, which allowed elementary excitations, such as phonons and magnons, to be observed directly. The Nobel citation was "for pioneering contributions to the development of neutron sca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectroscopy
Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Matter waves and acoustic waves can also be considered forms of radiative energy, and recently gravitational waves have been associated with a spectral signature in the context of the Laser Interferometer Gravitational-Wave Observatory (LIGO) In simpler terms, spectroscopy is the precise study of color as generalized from visible light to all bands of the electromagnetic spectrum. Historically, spectroscopy originated as the study of the wavelength dependence of the absorption by gas phase matter of visible light dispersed by a prism. Spectroscopy, primarily in the electromagnetic spectrum, is a fundamental exploratory tool in the fields of astronomy, chemistry, materials science, and physics, allowing the composition, physical structure and e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helmholtz-Zentrum Berlin Für Materialien Und Energie
Helmholtz-Zentrum Berlin für Materialien und Energie (Helmholtz Centre for Materials and Energy, HZB) is part of the Helmholtz Association of German Research Centres. The institute studies the structure and dynamics of materials and investigates solar cell technology. It also runs the third-generation BESSY II synchrotron in Adlershof. Until the end of 2019 it ran the 10 megawatt BER II nuclear research reactor at the Lise Meitner campus in Wannsee. History Following the renaming of Hahn-Meitner-Institut Berlin GmbH to Helmholtz-Zentrum Berlin für Materialien und Energie GmbH on 5 June 2008, the legal merger of Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung (BESSY) with HZB became visible on 1 January 2009. The Hahn-Meitner-Institut Berlin für Kernforschung (HMI), named after Otto Hahn and Lise Meitner, was named 14 March 1959 in Berlin-Wannsee to operate the BER I research reactor that began operation with 50 kW on 24 July 1958, then named Institut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HFIR
The High Flux Isotope Reactor (HFIR) is a nuclear research reactor at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, United States. Operating at 85 MW, HFIR is one of the highest flux reactor-based sources of neutrons for condensed matter physics research in the United States, and it has one of the highest steady-state neutron fluxes of any research reactor in the world. The thermal and cold neutrons produced by HFIR are used to study physics, chemistry, materials science, engineering, and biology. The intense neutron flux, constant power density, and constant-length fuel cycles are used by more than 500 researchers each year for neutron scattering research into the fundamental properties of condensed matter. HFIR has about 600 users each year for both scattering and in-core research. The neutron scattering research facilities at HFIR contain a world-class collection of instruments used for fundamental and applied research on the structure and dynamics of matter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ORNL
Oak Ridge National Laboratory (ORNL) is a U.S. multiprogram science and technology national laboratory sponsored by the U.S. Department of Energy (DOE) and administered, managed, and operated by UT–Battelle as a federally funded research and development center (FFRDC) under a contract with the DOE, located in Oak Ridge, Tennessee. Established in 1943, ORNL is the largest science and energy national laboratory in the Department of Energy system (by size) and third largest by annual budget. It is located in the Roane County section of Oak Ridge, Tennessee. Its scientific programs focus on materials, nuclear science, neutron science, energy, high-performance computing, systems biology and national security, sometimes in partnership with the state of Tennessee, universities and other industries. ORNL has several of the world's top supercomputers, including Frontier, ranked by the TOP500 as the world's most powerful. The lab is a leading neutron and nuclear power research facil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NIST
The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical science laboratory programs that include nanoscale science and technology, engineering, information technology, neutron research, material measurement, and physical measurement. From 1901 to 1988, the agency was named the National Bureau of Standards. History Background The Articles of Confederation, ratified by the colonies in 1781, provided: The United States in Congress assembled shall also have the sole and exclusive right and power of regulating the alloy and value of coin struck by their own authority, or by that of the respective states—fixing the standards of weights and measures throughout the United States. Article 1, section 8, of the Constitution of the United States, ratified in 1789, granted these powers to the new Congre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commissariat à L'énergie Atomique
The French Alternative Energies and Atomic Energy Commission or CEA ( French: Commissariat à l'énergie atomique et aux énergies alternatives), is a French public government-funded research organisation in the areas of energy, defense and security, information technologies and health technologies. The CEA maintains a cross-disciplinary culture of engineers and researchers, building on the synergies between fundamental and technological research. CEA is headed by a board headed by the general administrator (currently François Jacq since 20 April 2018), advised by the high-commissioner for atomic energy (currently Patrick Landais). Its yearly budget amounts to €5.1 billion and its permanent staff is slightly over 20,500 persons. It owned Areva. CEA was created in 1945; since then, the successive high-commissioners have been Frédéric Joliot-Curie, Francis Perrin, Jacques Yvon, Jean Teillac, Raoul Dautry, René Pellat, Bernard Bigot, Daniel Verwaerde and François Jacq. It c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diffractometer
A diffractometer is a measuring instrument for analyzing the structure of a material from the scattering pattern produced when a beam of radiation or particles (such as X-rays or neutrons) interacts with it. Principle Because it is relatively easy to use electrons or neutrons having wavelengths smaller than a nanometer, electrons and neutrons may be used to study crystal structure in a manner very similar to X-ray diffraction. Electrons do not penetrate as deeply into matter as X-rays, hence electron diffraction reveals structure near the surface; neutrons do penetrate easily and have an advantage that they possess an intrinsic magnetic moment that causes them to interact differently with atoms having different alignments of their magnetic moments. A typical diffractometer consists of a source of radiation, a monochromator to choose the wavelength, slits to adjust the shape of the beam, a sample and a detector. In a more complicated apparatus, a goniometer can also be used for fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polarized Neutron
Polarization or polarisation may refer to: Mathematics *Polarization of an Abelian variety, in the mathematics of complex manifolds *Polarization of an algebraic form, a technique for expressing a homogeneous polynomial in a simpler fashion by adjoining more variables *Polarization identity, expresses an inner product in terms of its associated norm * Polarization (Lie algebra) Physical sciences *Polarization (waves), the ability of waves to oscillate in more than one direction, in particular polarization of light, responsible for example for the glare-reducing effect of polarized sunglasses **Polarization (antenna), the state of polarization (in the above sense) of electromagnetic waves transmitted by or received by a radio antenna *Dielectric polarization, charge separation in insulating materials: **Polarization density, volume dielectric polarization ** Dipolar polarization, orientation of permanent dipoles **Ionic polarization, displacement of ions in a crystal **Maxwell†... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Institut Laue-Langevin
An institute is an organisational body created for a certain purpose. They are often research organisations (research institutes) created to do research on specific topics, or can also be a professional body. In some countries, institutes can be part of a university or other institutions of higher education, either as a group of departments or an autonomous educational institution without a traditional university status such as a "university institute" (see Institute of Technology). In some countries, such as South Korea and India, private schools are sometimes referred to as institutes, and in Spain, secondary schools are referred to as institutes. Historically, in some countries institutes were educational units imparting vocational training and often incorporating libraries, also known as mechanics' institutes. The word "institute" comes from a Latin word ''institutum'' meaning "facility" or "habit"; from ''instituere'' meaning "build", "create", "raise" or "educate". ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paul Scherrer Institut
The Paul Scherrer Institute (PSI) is a multi-disciplinary research institute for natural and engineering sciences in Switzerland. It is located in the Canton of Aargau in the municipalities Villigen and Würenlingen on either side of the River Aare, and covers an area over 35 hectares in size. Like ETH Zurich and EPFL, PSI belongs to the Swiss Federal Institutes of Technology Domain of the Swiss Confederation. The PSI employs around 2,100 people. It conducts basic and applied research in the fields of matter and materials, human health, and energy and the environment. About 37% of PSI's research activities focus on material sciences, 24% on life sciences, 19% on general energy, 11% on nuclear energy and safety, and 9% on particle physics. PSI develops, builds and operates large and complex research facilities and makes them available to the national and international scientific communities. In 2017, for example, more than 2,500 researchers from 60 different countries came to PS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutron Temperature
The neutron detection temperature, also called the neutron energy, indicates a free neutron's kinetic energy, usually given in electron volts. The term ''temperature'' is used, since hot, thermal and cold neutrons are moderated in a medium with a certain temperature. The neutron energy distribution is then adapted to the Maxwell distribution known for thermal motion. Qualitatively, the higher the temperature, the higher the kinetic energy of the free neutrons. The momentum and wavelength of the neutron are related through the de Broglie relation. The large wavelength of slow neutrons allows for the large cross section. Neutron energy distribution ranges But different ranges with different names are observed in other sources. The following is a detailed classification: Thermal A thermal neutron is a free neutron with a kinetic energy of about 0.025 eV (about 4.0×10−21 J or 2.4 MJ/kg, hence a speed of 2.19 km/s), which is the energy corresponding to the most proba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inelastic Neutron Scattering
Neutron scattering, the irregular dispersal of free neutrons by matter, can refer to either the naturally occurring physical process itself or to the man-made experimental techniques that use the natural process for investigating materials. The natural/physical phenomenon is of elemental importance in nuclear engineering and the nuclear sciences. Regarding the experimental technique, understanding and manipulating neutron scattering is fundamental to the applications used in crystallography, physics, physical chemistry, biophysics, and materials research. Neutron scattering is practiced at research reactors and spallation neutron sources that provide neutron radiation of varying intensities. Neutron diffraction (elastic scattering) techniques are used for analyzing structures; where inelastic neutron scattering is used in studying atomic vibrations and other excitations. Scattering of fast neutrons "Fast neutrons" (see neutron temperature) have a kinetic energy above ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
