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: 304 Search : act
refracted ray
  پرتو ِ شکسته   
partow-e šekasté (#)

Fr.: rayon réfracté   

A → light ray that undergoes a change of velocity and direction, as a result of interaction with the material medium in which it travels.

reflect; → ray.

refracting
  شکست؛ شکست‌گر   
šekast; šekastgar

Fr.: réfraction; à réfraction   

1) The action or result of the verb → refract.
2) Participial adjective of → refract.

From → refract + → -ing.

refracting prism
  منشور ِ شکست‌گر   
manšur-e šekastgar (#)

Fr.: prisme réfractant   

A prism that is used as a dispersing element in a spectrograph.

refracting; → prism.

refracting telescope
  تلسکوپ ِ شکستی، دوربین ِ ~   
teleskop-e šekasti (#), durbin-e ~ (#)

Fr.: lunette astronomique   

A telescope in which an image is formed by the refraction of light through a lens or lens system.

refracting; → telescope.

refraction
  شکست   
šekast (#)

Fr.: réfraction   

1) Optics: The change of direction which a beam of light undergoes as it enters a medium of different → refractive index.
2) Acoustics: The change in direction in sound waves on reaching the boundary between two media.
3) Seismology: The bending of a seismic wave as it enters a material of different density.

From L.L. refractionem (nominative refractio) "a breaking up," from L. refractus, p.p. of refringere "to break up," from re- "back" + combining form of frangere "to break," from PIE base *bhreg- "to break" (cf. Goth. brikan, O.E. brecan "to break;" Lith. brasketi "crash, crack").

Šekast, past stem of šekastan "to break, split;" Mid.Pers. škastan "to break;" Av. scind-, scand "to beak, cleave;" Proto-Iranian *skand- "to break, cleave;" PIE sken- "to cut off."

refractive index
  دیشن ِ شکست   
dišan-e šekast

Fr.: indice de réfraction   

Of any optical medium, the ratio of the → speed of light in vacuum (c) to that in the medium (v): n = c/v. The refractive index for vacuum, by definition, is 1. The refractive index of air is 1.00029 at standard temperature (25 °C) and pressure (1 atm). The refractive index of a medium depends on the wavelength of refracted wave. With light waves, n increases as the wavelength decreases. → Snell's law can be used to derive n. Same as → index of refraction.

Refractive, pertaining to → refraction; → index.

refractor
  شکست‌گر   
šekastgar (#)

Fr.: réfracteur   

Same as → refracting telescope.

Agent noun of refract, → refraction.

refractory
  سرکش، دیرگداز   
sarkeš, dirgodâz

Fr.: réfractaire   

A substance that has a high → melting point. It is therefore resistant to treatment and not easily melted or worked. The opposite of → volatile.

From refract, → refraction + adj. suffix -ory.

Sarkeš "refractory, disobedient, rebellious, stubborn," literally "withdrw, remove head," from sar "head" (variants soru, sorun "horn," karnâ "a trumpet-like wind instrument," variant sornâ "a wind instrument;" Mid.Pers. sar "head," sru "horn;" Av. sarah- "head," srū- "horn, nail;" cf. Skt. śiras- "head, chief;" Gk. kara "head," karena "head, top," keras "horn;" L. cornu "horn," cerebrum "brain;" P.Gmc. *khurnaz (Ger. Horn, Du. horen; cognate with E. horn, as above, from PIE *ker- "head, horn;" O.E. horn "horn of an animal," also "wind instrument;" E. horn); PIE base *ker- "head, horn, top, summit") + keš present stem of kešidan, kašidan "to draw; withdraw, remove" (dialectal Yaqnavi xaš "to draw," Qomi xaš "streak, stria, mark," Lori kerr "line;" Av. karš- "to draw; to plow," karša- "furrow;" Proto-Iranian *kerš-/*xrah- "to draw, plow;" cf. Skt. kars-, kársati "to pull, drag, plow;" Gk. pelo, pelomai "to move, to bustle;" PIE base kwels- "to plow").
Dirgodâz, literally "melting slowly, with delay," from dir "slowly, tardily; late" (Mid.Pers. dêr, variants dagr, drâz "long;" (Mod.Pers. derâz "long," variant Laki, Kurdi derež); O.Pers. darga- "long;" Av. darəga-, darəγa- "long," drājištəm "longest;" cf. Skt. dirghá- "long (in space and time);" L. longus "long;" Gk. dolikhos "elongated;" O.H.G., Ger. lang; Goth. laggs "long;" PIE base *dlonghos- "long") + godâz-, godâxtan "to melt" (Mid.Pers. vitâxtan, vitâcitan "to melt," from Av. vi-taxti- "flowing away, melting," from vi- "apart, away from, out" (O.Pers. viy- "apart, away;" cf. Skt. vi- "apart, asunder, away, out;" L. vitare "to avoid, turn aside") + tak- "to run, to flow," taciāp- "flowing water," tacinti (3pl.pers.act.) "to flow," tacar- "course," tacan "current, streaming;" Mod.Pers. tâz-, tâxtan "to run; to hasten; to assault," tâzi "swift (greyhound)," tak "running, rush;" Mid.Pers. tâz-, tâxtan "to flow, to cause to walk," tc- "to flow, to walk," tag "running, attack," tâzig "swift, fast;" Khotanese ttajs- "to flow, to walk;" cf. Skt. tak- "to rush, to hurry," takti "runs;" O.Ir. tech- "to flow;" Lith. teketi "to walk, to flow;" O.C.S. tešti "to walk, to hurry;" Tokharian B cake "river;" PIE base *tekw- "to run; to flow").

relative refractive index
  دیشن ِ شکستی ِ بازانی   
dišan-e šekasti-ye bâzâni

Fr.: indice de réfraction relatif   

The ratio of the sine of the angle of incidence to the sine of the angle of refraction for a ray passing out of one of the media into the other.

relative; → refractive; → index.

research reactor
  واژیرگر ِ پژوهشی   
vâžirgar-e pažuheši

Fr.: réacteur de recherche   

A nuclear reactor designed for radionuclide production, materials testing, and training.

research; → reactor.

resonant reaction
  واژیرش ِ باز‌آوا   
vâžireš-e bâzâvâ

Fr.: réaction résonnante   

A nuclear reaction whose probability is enhanced at an energy corresponding to an energy level of one of the nuclei. → resonance capture.

Resonant, verbal adj. of → resonate; → reaction.

scale factor
  کروند ِ مرپل   
karvand-e marpel

Fr.: facteur d'échelle   

Math.: A number which scales, or multiplies, some quantity. In the equation y = Cx, C is the scale factor for x. C is also the coefficient of x, and may be called the constant of proportionality of y to x.
Geometry: The ratio of any two corresponding lengths in two similar geometric figures. The ratio of areas of two similar figures is the square of the scale factor.

scale; → factor.

scientific fact
  باشای ِ دانشی، ~ دانشیک   
bâšâ-ye dâneši, ~ dânešik

Fr.: fait scientifique   

An agreement by competent observers of a series of observations of the same phenomena. From time to time scientific facts are revised by additional data (G. Smooth, Lawrence Berkeley Lab website).

scientific; → fact.

screened Coulomb interaction
  اندرژیرش ِ باپرده‌ی ِ کولن   
andaržireš-e bâparde-ye Coulomb

Fr.: interaction de Coulomb écrantée   

The → Coulomb interaction reduced owing to the presence of other electrons. See → shielding effect.

screen; → coulomb; → interaction.

second contact
  پرماس ِ دوم   
parmâs-e dovom

Fr.: deuxième contact   

The beginning of the total phase of a solar eclipse when the leading edge of the Moon touches the eastern edge of the Sun completely obscuring the Sun.

second; → contact.

simple fraction
  برخه‌ی ِ ساده   
barxe-ye sâdé

Fr.: fraction simple   

A fraction in which the → numerator and → denominator are positive → integer numbers. Compare → compound fraction.

simple; → fraction.

sky subtraction
  زیرکرشش ِ آسمان   
zirkaršeš-e âsmân

Fr.: soustraction de ciel   

The act or instance of removing the contribution of non-related, intervening foreground light to the object.

sky; → subtraction.

solar activity
  ژیرندگی ِ خورشید   
žirandegi-ye xoršid

Fr.: activité solaire   

The general term for all forms of short-lived phenomena on the Sun, including → solar flares, → sunspots, → prominences, etc., indicating that the Sun is an active star.

solar; → activity.

solar activity cycle
  چرخه‌ی ِ ژیرندگی ِ خورشید   
carxe-ye žirandegi-ye xoršid

Fr.: cycle d'activité solaire   

Same as the → solar cycle.

solar activity; → cycle.

strong interaction
  اندرژیرش ِ سترگ   
andaržireš-e sotorg

Fr.: interaction forte   

The interaction between quarks that is transmitted by gluons. The characteristic range of the strong interaction is 10-13 cm, and the time scale over which it operates is on the order of 10-23 second. Also called → strong force.

strong; → interaction.

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