Fr.: temps de passage
The time interval between the release of an electron at the photocathode and the arrival of an electron at the anode. Transit time is not a single-valued quantity, but has a bell-shaped distribution.
Transiting Exoplanet Survey Satellite (TESS)
mâhvâre-ye bardid-e borun-sayyârehâ-ye gozarandé
A → NASA space telescope devoted to the hunt for planets orbiting the brightest stars in the sky, launched on April 18, 2018. The mission is planned to monitor at least 200,000 stars for signs of → exoplanets using the → planetary transit method. TESS is equipped with four identical refractive → cameras with a combined → field of view (FOV) of 24 × 96 degrees. Each camera consists of a → CCD detector assembly, a → lens assembly, and a lens hood. The → entrance pupil diameter is 10.5 cm and the wavelength range 600 to 1,000 nm. The satellite is a follow-up of NASA's → Kepler spacecraft, but focuses on stars that are 30 to 100 times brighter than those Kepler examined.
Fr.: planète en transit
TRAnsiting Planets and PlanetesImals Small Telescope (TRAPPIST)
A Belgian facility devoted to the detection and characterization of → exoplanets and to the study of → comets (→ transiting planet) and other → small solar system bodies. It consists of two 60 cm robotic telescopes located at the → European Southern Observatory, → La Silla, in Chile and at Oukaïmden Observatory in Marroco.
1) Passage from one position, state, stage, subject, concept, etc., to another.
From L. transitionem (nominative transition) "a going across or over," noun of action from transire "go or cross over," from → trans- "across" + ire "to go."
gerde-ye gozaresh, disk-e ~
Fr.: disque de transition
The → accretion disk of a → T Tauri star that displays very weak or no → infrared excess at → near infrared wavelengths, but shows strong excess at → intermediate infrared and longer wavelengths. This happens when the hot inner dust disk has dissipated whereas the cooler outer disk is still intact.
Fr.: fonction de transition
Fr.: probabilité de transition
The probability that a quantum-mechanical system will make a transition from a given initial state to a given final state.
Fr.: flux de transition
Math.: A permutation of a set of elements that interchanges two elements and
leaves the remaining elements in their original positions.
For example, the swapping of 2 and 5 to take the list 123456 to 153426 is a transposition.
Fr.: position vraie
The coordinates of an object for a given date, with respect to the true equator and the true equinoxes for the instant of time in question.
An institution of higher education composed of several faculties for teaching and research and authorized to grant academic degrees.
M.E., from O.Fr. universitei, from M.L. universitatem (nominative. universitas), in L.L. "corporation, society," from L., "the whole, aggregate," from universus "whole, entire," → universe.
Dânešgâh, from dâneš, → science, + -gâh "place; time" (Mid.Pers. gâh, gâs "time;" O.Pers. gāθu-; Av. gātav-, gātu- "place, throne, spot;" cf. Skt. gâtu- "going, motion; free space for moving; place of abode;" PIE *gwem- "to go, come").
gozar-e zabarin (#)
Fr.: passage supérieur
The movement of a celestial body across a celestial meridian's upper branch. Same as → upper culmination.
Fr.: densité de vecteur
Fr.: transition vibrationnelle
Fr.: transition vibrationnelle-rotationnelle
The property of a → fluid that resists the force tending to cause the fluid to flow. Viscosity may be thought of as the internal → friction of two fluid layers which flow parallel to each other at different speeds. The cause of viscosity is the transport of → momentum by the molecules from one layer to the other. Viscosity is given by η = φ.u.λ.ρ, where φ is a coefficient which depends on the nature of the interaction between the molecules, u is the average velocity of thermal motion of the molecules, λ is the → mean free path, and ρ the → density of the fluid. Also called → dynamic viscosity or → absolute viscosity. See also → kinematic viscosity.
weight of a tensor density
vazn-e cagâli-ye tânsor
Fr.: poids d'une densité de tenseur
A constant the value of which is characteristic for any given → tensor density.
Fr.: luminosité de vent
The final kinetic energy of the → stellar wind expressed by: (1/2)Mdot.v∞2 = (1/2)(v∞/c)L For an O6 star, L ~ 3 x 105Lsun and v∞ ~ 2000 km s-1, which give a wind luminosity of ~ 1 x 1037 erg s-1, about 1% of the → stellar luminosity. See also → photon tiring limit.