joft-e elektron-pozitron (#)
Fr.: paire électron-positron
bâl-e parâkaneš-e elektron
A → line broadening phenomenon involving the scattering effect of → free electrons on the → radiation transfer in → stellar atmospheres. The scattering of radiation by free electrons plays an important role in the atmospheres of → hot stars, such as → O-types, early → B-types, and → Wolf-Rayet stars. The first detailed study of electron scattering in Wolf-Rayet stars was by Castor et al. (1970), who used electron scattering to explain the broad emission wings of N IV λ3483 in HD 192163. In → P Cygni stars the explanation of the very extended (almost symmetric) wings on the → Balmer lines as caused by electron scattering was first made by Bernat & Lambert (1978). Hillier (1991) showed that significant reduction in the strength of an electron-scattering wing can be achieved in a model of → clumped wind for a lower mean → mass loss rate. This resulted in a better agreement between observations and theoretical predictions. Electron-scattering wings provide diagnostics regarding the presence of density inhomogeneities in → stellar winds (Münch, 1948, ApJ 108, 116; Hillier, 1991, A&A 247, 455).
1) elektroni (#); 2) elektronik (#)
Fr.: état éléctronique
In molecular quantum mechanics, any of → quantum states corresponding to a particular → electron configuration (i.e. an arrangement of the electron(s) in certain → orbitals). The electron configuration with the lowest energy is called the → ground state. All higher energy states are called → excited states.
Fr.: transition électronique
An instrument for detecting electric charges or → potential differences.
Referring to electric charges at rest.
Fr.: charge électrostatique
A quantity of electricity at rest on the surface of an insulator or an insulated conductor.
meydân-e barqistâ (#)
Fr.: champ électrostatique
A region of space in which a non-moving → electric charge would be subjected to a force of attraction or repulsion as a result of the presence of another stationary electric charge. The electrostatic field is a special case of the → electromagnetic field.
Fr.: induction électrostatique
The production of stationary electric charges on an uncharged object as a result of a charged body being brought near it without touching it. A positive charge will induce a negative charge, and vice versa.
electrostatic unit (esu)
yekâ-ye barqistâ-ye bâr
Fr.: unité électrostatique de charge
The unit of electric charge in the → cgs system of units. Also called the → statcoulomb. The esu is defined such that if two objects, each carrying a charge of +1 esu, are 1 cm aparat, then they repel each other with a force of 1 → dyne. 1 esu = 3.3356 × 10-10 → coulombs.
Fr.: onde électrostatique
In a → plasma, a disturbance that is devoid of magnetic field, and hence can be expressed by an electrostatic potential. The electric field is always parallel to the propagation vector, so that the electrostatic wave is → longitudinal.
The branch of → electricity dealing with the phenomena and properties of stationary → electric charges, as opposed to → electrodynamics. It involves the build-up of charge on the → surface of → objects due to → contact with other surfaces.
Fr.: époque électrofaible
A period in the early history of the Universe lasting from 10-36 to 10-12 seconds after the → Big Bang. The electroweak epoch begins at the same time as cosmic → inflation is triggered. This is also the time when the → strong force breaks from the → grand unified force and ends with another → phase transition will occur in which the → weak interaction breaks from the → electroweak force.
niru-ye barqânezâr, ~ barqâkamzur
Fr.: force électrofaible
The force that takes part in an → electroweak interaction.
Fr.: interaction électrofaible
The unified description of two of the four fundamental interactions of nature, → electromagnetism and the → weak interaction which would merge into a single force under conditions of extreme temperature (above 1016 degrees, 102 GeV) prevalent in the early history of the → Universe.
Fr.: étoile électrofaible
A postulated type of star that could form toward the end of a → massive star's life, after → nuclear fusion has stopped in its → core, and before the star → collapses into a → black hole. In those → extreme conditions, when → temperature and → density inside the star are very high, → quarks could convert into → leptons. Hence huge amounts of energy can be released, much of which would be in the form of → neutrinos.