An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 483
brecciate
  برشیدن   
berešidan

Fr.: bréchifier   

To form as → breccia.

From → breccia + → -ate.

brecciated
  برشیده، برشمند   
berešidé, beršmand

Fr.: bréchifié   

Characterized by, converted into, or resembling a breccia; especially of a rock structure marked by an accumulation of angular fragments, or of an ore texture showing mineral fragments without notable rounding.

breccia, → brecciated.

brecciated rock
  سنگ ِ برشیده   
sang-e berešidé

Fr.: roche bréchifiée   

A rock formed by the process of → brecciation.

brecciated; → rock.

brecciation
  برشش   
berešeš

Fr.: bréchification   

The formation of → breccia.

Verbal noun of → brecciate.

breeze
  نسیم   
nasim (#)

Fr.: brise   

A wind or current of air, especially a light or moderate one (2-14 m/sec).

From O.Sp. briza "cold northeast wind;" alternatively from East Frisian brisen "to blow fresh and strong."

Nasim "gentle breeze," from Ar.

Breit-Wheeler process
  فراروند ِ برایت-ویلر   
farâravand-e Breit-Wheeler

Fr.: processus Breit-Wheeler   

The production of an → electron-positron pair in the → collision of two → gamma ray → photons (γγ → e+e-). It is the → inverse process of → Dirac annihilation (e+e-→ γγ). The Breit-Wheeler process is the simplest way by which pure → light can be potentially transformed into → matter. However, as of 2014, this process has never been observed in practice because of the difficulty in preparing colliding → gamma ray beams.

Breit, G. & Wheeler, J. A. 1934, Collision of two light quanta. Phys. Rev. 46, 1087; → process.

bremsstrahlung
  لگام-تابش   
legâm-tâbeš

Fr.: rayonnement de freinage, bremsstrahlung   

The → electromagnetic radiation emitted by a → fast moving → charged particle when it passes within the strong → electric field of an → atomic nucleus and is → decelerated.

Bremsstrahlung, from Ger. Bremse "brake" + Strahlung "radiation," from strahlen "to radiate," from Strahl "ray," from O.H.G. strala "arrow, stripe;" PIE *ster- "to spread."

Legâm-tâbeš, from legâm, → brake, + tâbeš, → radiation.

Brewster angle
  زاویه‌ی ِ بروستر   
zâviye-ye Brewster (#)

Fr.: angle de Brewster   

The → angle of incidence for which the sum of the incident angle and the → angle of refraction is 90°. The value of Brewster's angle for glass is 57° and for water is 53°. Same as → polarizing angle.

Brewster's law; → angle.

Brewster point
  نقطه‌ی ِ بروستر   
noqte-ye Brewster

Fr.: point de Brewster   

A → neutral point located 15 to 20° directly below the Sun.

Brewster's law; → point

Brewster's law
  قانون ِ بروستر   
qânun-e Brewster

Fr.: loi de Brewster   

The amount of the polarization of light reflected from a surface is a maximum when the reflected ray is at right angles to the refracted ray. See also → polarizing angle.

Named after Sir David Brewster (1781-1868), Scottish physicist; → law.

bridge
  پل   
pol (#)

Fr.: pont   

1) An apparent structure of → gas or → stars linking one → galaxy to another, such as → Magellanic Bridge.
2) Any one of a variety of → elctrical networks in which one branch connects two points of equal → potential and so carries no → current when the → circuit is suitably adjusted.
3) In → graph theory, a simple → edge whose removal disconnects a → graph.

M.E. brigge, O.E. brycge, from P.Gmc. *brugjo (cf. Ger. Brücke), from PIE *bhru- "log, beam."

Pol, Mid.Pers. puhl,, Av. pərətav- "bridge, passage."

bright
  درخشان، روشن   
deraxšân, rowšan

Fr.: brillant   

Giving out or reflecting much light, shining.

O.E. bryht, from beorht "bright, splendid," from P.Gmc. *berkhiaz, from PIE base *bhereg- "to gleam, white" (cf. Av. brāz- "to shine, gleam, flash, radiate," Skt. bhrajate "shines, glitters," Mod.Pers. balk, warq, barx, barq "flash, flame, light," barâz "beauty, grace, elegance," barâzidan "to render good, beautiful," Lith. breksta "to dawn," Welsh berth "bright, beautiful," L. flagrare "to blaze"). → electricity.

Deraxšân and rowšan both from M.P. rôc, O.Pers. raucah-, Av. raocah- "light, luminous; daylight;" cf. Skt roka- "brightness, light", cognate with Gk. leukos "white, clear", L. lux "light" (also lumen, luna), PIE *leuk- "light, brightness". The Mod.Pers. words ruz "day," foruq "light", and afruxtan "to light, kindle" also belong to this family, as well as the E. light, Ger. Licht, and Fr. lumière.

bright giant
  غول ِ تابناک   
qul-e tâbnâk

Fr.: géante lumineuse   

An → evolved star which is more → luminous than normal → giant stars (→ luminosity class III) and between ordinary giants and → supergiants (class I). It is denoted by the symbol II. Examples are → Canopus and → Adhara.

bright; → giant.

bright nebula
  میغ ِ روشن، ~ درخشان   
miq-e rowšan, ~ deraxšân

Fr.: nébuleuse brillante   

In contrast to a → dark nebula, a bright cloud of interstellar gas and dust. The term designates both emission nebulae and reflection nebulae.

bright; → nebula.

brightening
  روشنش   
rowšaneš

Fr.: embrillancement   

The act or process of becoming bright or brighter. → limb brightening, → gravity brightening

Verbal noun of brighten, from → bright.

brightness
  درخشندگی   
deraxšandegi (#)

Fr.: brillance   

General:The state or quality of being bright.
Astronomy:The amount of light or other radiation received from a celestial object. It depends on the intrinsic brightness of the object, its distance and the amount of interstellar extinction. → luminosity.

bright + → -ness.

Deraxšandegi, from deraxš, present stem of deraxšidan "to shine," → bright, + -andé adjective suffix + -gi noun suffix.

brightness distribution
  واباژش ِ درخشندگی   
vâbâžeš-e deraxšandegi

Fr.: distribution de brillance   

A statistical distribution of the brightness of an astronomical extended object.

brightness; → distribution.

Vâbâžeš, → distribution; deraxšandegi, → brightness.

brightness temperature
  دما‌ی ِ درخشندگی   
damâ-ye deraxšandegi

Fr.: température de brillance   

In radio astronomy, the temperature of a source calculated on the assumption that it is a blackbody emitting radiation of the observed intensity at a given wavelength. → antenna temperature.

brightness; → temperature.

Brillouin function
  کریای ِ بری‌یویءن   
karyâ-ye Brillouin

Fr.: fonction de Brillouin   

A mathematical function appearing in the → magnetization equation of a → paramagnetic substance.

Brillouin zone; → zone.

Brillouin scattering
  پراکنش ِ بری‌یویءن   
parâkaneš-e Brillouin

Fr.: diffusion de Brillouin   

Scattering of electromagnetic waves in solids and liquids when, as a result of the scattering process, an acoustic → phonon is emitted or absorbed. Brillouin scattering is analogous to → Raman scattering.

Brillouin zone; → scattering.

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