An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



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Number of Results: 703
recombination era
  دوران ِ بازمیازش   
dowrân-e bâzmiyâzeš

Fr.: ère de recombinaison   

The era some 380,000 years after the → Big Bang (at a → redshift of about 1,100), when the Universe had cooled sufficiently so that protons and electrons combined to form → neutral hydrogen in a process called → recombination. The temperature was about 3,000 K and the ionization fraction low enough for Universe to become transparent to light. Consequently matter and radiation decouple from one another because no further → scattering of the radiation occurs. The observation of the → cosmic microwave background radiation provides a means of studying the Universe at the recombination era. Also called recombination epoch and → decoupling era.

recombination; → era.

recombination line
  خط ِ بازمیازش   
xatt-e bâzmiyâzeš

Fr.: raie de recombinaison   

An → emission line in a spectrum produced in an → H II region when a free electron combines with an ionized atom to form a neutral atom or an ion of lower → ionization stage. Same as → free-bound emission.

recombination; → line.

recombination radiation
  تابش ِ بازمیازش   
tâbeš-e bâzmiyâzeš

Fr.: rayonnement de recombinaison   

Radiation produced when a free electron in a plasma is captured by an ionized atom.

recombination; → radiation.

recombination rate
  نرخ ِ بازمیازش   
nerx-e bâzmiyâzeš

Fr.: taux de recombinaison   

In → H II regions the rate at which free electrons recombine with → ionized hydrogen atoms (protons).

recombination; → rate.

recombination time
  زمان ِ بازمیازش   
zamân-e bâzmiyâzeš

Fr.: temps de recombinaison   

The time period necessary for a cloud of atomic hydrogen to be → ionized by the ultraviolet photons of a central → massive stars.

recombination; → time.


Fr.: recombiner, se recombiner   

To combine or put together again. To undergo or cause recombination.

re- + → combine.

  ۱) واگت؛ ۲) واگتیدن   
1) vâgat; 2) vâgatidan

Fr.: 1) enregistrement; 2) enregistrer   

1a) An act of recording.
1b) The state of being recorded, as in writing.
1c) Something on which sound or images have been recorded for subsequent reproduction, as a grooved disk that is played on a phonograph or an optical disk for recording sound (audiodisk) or images (videodisk).
2a) To set down in writing or the like, as for the purpose of preserving evidence.
2b) To set down or → register in some permanent form, as on a seismograph.
2c) To set down, register, or fix by characteristic marks, incisions, magnetism, etc., for the purpose of reproduction by a phonograph or magnetic reproducer; to make a recording of.

From M.E. recorden "to repeat, to report," from O.Fr. recorder "to get by heart," from L. recordari "to call to mind, remember," from → re- "back, again" + cor "heart" (as the metaphoric seat of memory, as in learn by heart).

Vâgat literally "to take, seize, to take back," cf. Ger. aufnehmen "to record," from nehmen "to take;" E. "take down" "to note down;" Šahmirzâdi vagatan "to take," Lâhijâni vitan "to take, seize," Aftari veytu "to take," Delijâni bitan "to take," var of Tâleši gate, Târi gata/ger, Sorxeyi gil, variants of gereftan, → concept.

râstgušé (#)

Fr.: rectangle   

A → quadrilateral all of whose angles are → right angles.

M.Fr. rectangle, from M.L. rectangulum "a triangle having a right angle," from rect-, combining form of rectusright + angulum, → angle.

Râstgušé, from râst, → right, + gušé "corner, angle;" Mid.Pers. gôšak "corner."

râstguš (#)

Fr.: ractangulaire   

Having the base or section in the form of a rectangle. Shaped like a rectangle.

Adj. of → rectangle.

rectangular window
  روزنه‌ی ِ راستگوش   
rowzane-ye râstguš

Fr.: fenêtre rectangulaire   

A → window function that is constant inside a specified interval.

rectangular; → window.


Fr.: rectification   

1) Math.: The process of determining the length of a curve.
2) Physics: Conversion of an alternating into a direct current.
3) Astro.: The process of rectifying a spectrum.

Verbal noun of → rectify.

rectified spectrum
  بیناب ِ راستیده   
binâb-e râstidé

Fr.: spectre rectifié   

A spectrum after correction for detector's → baseline.

Rectified p.p. of → rectify; → spectrum.


Fr.: rectificateur   

1) General: A person or thing that rectifies.
2) Physics: A device for transforming an → alternating current into a → direct current.

Agent noun of → rectify.

  راستیدن، راست گرداندن   
râstidan, râstgardândan

Fr.: rectifier   

1) General: To make, put, or set right; to correct.
2) Electricity: To convert an → alternating current into a → direct current.
3) Chem.: To refine a substance, especially by repeated distillation or sublimation.

M.E. rectifien, from O.Fr. rectifier "to make straight," from L.L. rectificare "make right," from L. rectus "straight," cognate with Pers. râst, as below, → right + root of facere "to make, do, perform" (cf. Fr. faire, Sp. hacer), from PIE base *dhe- "to put, to do" (cf. Mod.Pers. dâdan "to give;" O.Pers./Av. dā- "to give, grant, yield," dadāiti "he gives; puts;" Skt. dadáti "puts, places;" Hitt. dai- "to place;" Gk. tithenai "to put, set, place;" Lith. deti "to put;" Czech diti, Pol. dziac', Rus. det' "to hide," delat' "to do;" O.H.G. tuon, Ger. tun, O.E. don "to do").

Râstidan, literally "to make straight, right," infinitive from râst cognate with L. rectus "straight," → right.

râst-xatt (#)

Fr.: rectiligne   

In a straight line; consisting of straight lines. → curvilinear

From recti- combining form of rectus, → right, + → line + -ar, variant of the adjective-forming suffix → -al.

Râst-xatt, from râst, → right, + xattline.

rectilinear propagation of light
  توچش ِ راست‌خط ِ نور   
tuceš-e râst-xatt-e nur

Fr.: propagation rectiligne de la lumière   

The motion of light in the first approximation, as evidenced from the formation of shadows and other every day experience. However, → diffraction

rectilinear; → propagation; → light.

rectilinear system
  راژمان ِ راست‌خط   
râžmân-e râst-xatt

Fr.: système rectilinéaire   

An optical system that is corrected for → distortion and → spherical aberration and therefore forms the image of a straight line as a straight line.

rectilinear; → system.


Fr.: se reproduire périodiquement, revenir   

To occur again, as an event, experience, etc.

From L. recurrere "to return, run back," → re- + currere "to run," → current.

Bâzâmadan "to come back, return," from bâz, → re-, + âmadan "to come, arrive, become" (present stem ây-); Av. ay- "to go, to come," aēiti "goes;" O.Pers. aitiy "goes;" Skt. e- "to come near," eti "arrival;" L. ire "to go;" Goth. iddja "went;" Lith. eiti "to go;" Rus. idti "to go."


Fr.: récurrence   

1) An act or instance of recurring.
2) Return to a previous condition, habit, subject, etc. ( → recurrence relation.

Verbal noun of → recur.

recurrence relation
  باز‌آنش ِ باز‌آمد   
bâzâneš-e bâzâmad

Fr.: relation de recurrence   

A → sequence based on a → rule that gives the next → term as a → function of the previous term(s). For example, the sequence 3, 9, 21, 45,... can be represented by the recurrence relation un+1 = 2un + 3, where u1 = 3 and n ≥ 1.

recurrence; → relation.

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