- hyperfine splitting frequency
- Метрология: частота перехода в расщеплённой сверхтонкой структуре
Универсальный англо-русский словарь. Академик.ру. 2011.
Универсальный англо-русский словарь. Академик.ру. 2011.
Hyperfine structure — In atomic physics, hyperfine coupling is the weak magnetic interaction between electrons and nuclei. Hyperfine coupling causes the hyperfine splitting of atomic or molecular energy levels. The totality of energy levels spawned by hyperfine… … Wikipedia
New SI definitions — The seven SI base units and the interdependency of their current definitions A committee of the International Committee for Weights and Measures (CIPM) has proposed revised formal definitions of the SI base units, which are being examined by the… … Wikipedia
Kilogram — Kg redirects here. For other uses, see Kg (disambiguation). Kilogram A computer generated image of the international prototype kilogram (IPK). The IPK is the kilogram. The IPK, which is roughly the size of a golf ball, sits here alongside a ruler … Wikipedia
Electron paramagnetic resonance — (EPR) or electron spin resonance (ESR) spectroscopy is a technique for studying chemical species that have one or more unpaired electrons, such as organic and inorganic free radicals or inorganic complexes possessing a transition metal ion. The… … Wikipedia
Precision tests of QED — Quantum electrodynamics (QED), a relativistic quantum field theory of electrodynamics, is among the most stringently tested theories in physics.Precision tests of QED consist of measurements of the electromagnetic fine structure constant, α, in… … Wikipedia
Mössbauer spectroscopy — A Mössbauer absorption spectrum of 57Fe Mössbauer spectroscopy is a spectroscopic technique based on the Mössbauer effect. This effect, discovered by Rudolf Mössbauer in 1957, consists in the recoil free, resonant absorption and emission of gamma … Wikipedia
Atomic clock — Nuclear clock redirects here. For the clock as a measure for risk of catastrophic destruction, see Doomsday Clock. For a clock updated by radio signals (commonly but inaccurately called an atomic clock ), see Radio clock. For the album by Zion I … Wikipedia
Hydrogen line — For hydrogen lines in general, see Hydrogen spectral series. The hydrogen line, 21 centimeter line or HI line refers to the electromagnetic radiation spectral line that is created by a change in the energy state of neutral hydrogen atoms. This… … Wikipedia
Photon — This article is about the elementary particle of light. For other uses, see Photon (disambiguation). Photon Photons emitted in a coherent beam from a laser Composition Elementary particle … Wikipedia
Diazenylium — N2H+, known as diazenylium, was one of the first ions to be observed in interstellar clouds. Since then, it has been observed for a variety of purposes in several different types of interstellar environments. It gives astronomers information… … Wikipedia
Second — This article is about the unit of time. For other uses, see Second (disambiguation). A light flashing approximately once per second. The second (SI unit symbol: s; informal abbreviation: sec) is a unit of measurement of time, and is the… … Wikipedia