hyperfine interaction energy
21Rho meson — In particle physics, a rho meson is a short lived hadronic particle that is an isospin triplet whose three states are denoted as SubatomicParticle|Rho+, SubatomicParticle|Rho0 and SubatomicParticle|Rho . After the pions and kaons, the rho mesons… …
22spectroscopy — spectroscopist /spek tros keuh pist/, n. /spek tros keuh pee, spek treuh skoh pee/, n. the science that deals with the use of the spectroscope and with spectrum analysis. [1865 70; SPECTRO + SCOPY] * * * Branch of analysis devoted to identifying… …
23magnetic resonance — Absorption or emission of electromagnetic radiation by electrons or atomic nuclei in response to certain magnetic fields. The principles of magnetic resonance are used to study the atomic and nuclear properties of matter; two common laboratory… …
24Electron 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… …
25Mössbauer 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 …
26Photon — 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 …
27Hydrogen 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… …
28Angular momentum coupling — Coupling in science Classical coupling Rotational–vibrational coupling Quantum coupling Quantum mechanical coupling Rovibrational coupling Vibronic coupling Rovibronic coupling Angular momentum coupling …
29Precision 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… …
30Fine-structure constant — The fine structure constant or Sommerfeld fine structure constant, usually denoted alpha ,, is the fundamental physical constant characterizing the strength of the electromagnetic interaction.It is a dimensionless quantity, and thus its numerical …
