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: 40 Search : band
abandon
  راچیدن   
râcidan

Fr.: abandonner   

1) To leave completely and finally; forsake utterly; desert.
2) To give up; discontinue; withdraw from (Dictionary.com).

M.E. abando(u)nen, from M.Fr. abandoner, from O.Fr. abandoner from adverbial phrase à bandon "at will, at discretion," from à "at, to," → ad-, + bandon "power, jurisdiction," from L. bannum "proclamation."

Râcidan, related to Pers. parhêz, parhiz "to keep away from, abstain, avoid," gurêz, goriz "to flee, run away;" Av. raēc- "to leave, let;" → heritage.

absorption band
  باند ِ درشمی   
bând-e daršami

Fr.: bande d'absorption   

1) A series of very closely spaced absorption lines in stellar spectra resulting from the absorption of light by molecules. Bands caused by titanium oxide (→ TiO bands) and carbon compounds occur in the spectra of low temperature M and C stars.
2) A range of wavelengths, usually in electromagnetic radiation, that are absorbed by a given substance. Absorption bands are characteristic of molecules and correspond to changes of electron orbits in the molecules. See also → anomalous dispersion.

absorption; → band.

Alexander's dark band
  نوار ِ سیاه ِ الکساندر   
navâr-e siyâh-e Aleksânder

Fr.: bande noire d'Alexandre   

A dark space or band between the primary and secondary rainbows when both are visible. This effect is due to the minimum refraction angle for the → primary rainbow and the maximum for the → secondary rainbow. The only light in the dark region is caused by (a small amount of) scattering, and not the refraction of light in water droplets.

Named for Alexander of Aphrodisias, Greek Peripatetic philosopher and commentator, who first described the effect in 200 AD.

allowed band
  باند ِ پرزامیده   
bând-e parzâmidé

Fr.: bande permise   

In solid-state physics, the range of energies which electrons can attain in a material.

P.p. of v. allow, from O.Fr. alouer "approve," from L. allaudare , compound of → ad- "to" + laudare "to praise."

Bând, → band; parzâmidé, p.p. of parzâmidan "to send through, permit, allow," from parzâm "permission," from par- "through" + zâm stem of zâmidan, Mid.Pers. zâmenidan "to send, lead;" → permit

Aromatic Infrared Band (AIB)
  باند ِ فروسرخ ِ اروماتیک   
bând-e forusorx-e aromâtik

Fr.: bande infrarouge aromatique   

A family of strong infrared emission bands at 3.3, 6.2, 7.7, 8.6, 11.3, and 12.7 μm which are widely observed in a large variety of objects, such as → H II regions, → reflection nebulae, → planetary nebulae, and the → diffuse interstellar medium of our galaxy and other galaxies. Solar system objects, such as carbonaceous → meteorites and → interplanetary dust particles are also known to display these features. They are suggested to be due to → polycyclic aromatic hydrocarbons.

aromatic; → infrared; → band.

band
  باند   
bând (#)

Fr.: bande   

General:1) A strip serving to encircle and bind one object or to hold a number of objects together. 2) A strip or stripe that contrasts with something else in color, texture, or material.
Physics: 1) A specific range of wavelengths or frequencies of electromagnetic radiation.
2) Closely packed spectral lines that appear to form a continuous group. → absorption band; → emission band.

From M.E. bende, O.E. bend, from O.Fr. bande, bende, P.Gmc. *bindan, from PIE *bendh- "to bind" (cf. Goth bandi "that which binds;" Av./O.Pers. band- "to bind, fetter," banda- "band, tie," Skt. bandh- "to bind, tie, fasten," bandhah "a tying, bandage."

Bând, adoption from E. band, which is cognate and synonymous with Pers. band, present tense stem of bastan "to bind, shut," Mid.Pers. bastan, band, Av./O.Pers. band-, as explained above. See also → strip.

band head
  باندسر، سر ِ باند   
bândsar, sar-e bând

Fr.: tête de bande   

A location on the spectrogram of a molecule at which the lines of a band stack.

Band head, from → band + head, from O.E. heafod "top of the body," also "upper end of a slope," also "chief person, leader," from P.Gmc. *khaubuthan, from PIE *kauput- "head" (cf. Skt. kaput-, L. caput "head," Lori kapu "head," kapulek "skull, middle of the head").

Bândsar, from → bând + sar "head," soru, sorun "horn," karnâ "a trumpet-like wind instrument" (originally made from animal horns), 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 (E. horn; Ger. Horn, Du. horen), from PIE *ker- "head, horn."

band spectrum
  بیناب ِ باندی   
binâb-e bândi

Fr.: spectre de bande   

A spectrum which consists of a number of bands each having one sharp edge. Each band is composed of a large number of closely spaced emission or absorption lines. Band spectra are typical of molecules. Bands produced by titanium oxide, zirconium oxide, and carbon compounds are characteristic of low temperature stars.

Band spectrum, from → band + → spectrum.

Binâb-e bândi, from binâb, → spectrum + bândi, relating to bând, → band.

band-pass
  گذر-باند   
gozar-bând

Fr.: bande passante   

A range of frequencies that can pass through a filter such as one in an electrical circuit.

From → band + pass, from O.Fr. passer, from V.L. *passare "to step, walk, pass," from L. passus "step, pace;" cf. Pers. "foot," pey "step."

Gozar-bând, from gozar "passage, transit, passing," gozaštan "to pass, cross, transit," from Mid.Pers. vitârtan + bând, → band.

bandpass filter
  پالایه‌ی ِ گذر-باند   
pâlâye-ye gozar-bând

Fr.: filtre de bande   

An electric filter that transmits a known band of frequencies but suppresses unwanted frequencies above and below this band.

bandpass; → filter.

bandwidth
  باند-پهنا   
bândpahnâ

Fr.: largeur de bande   

The portion of the electromagnetic spectrum that is permitted to pass through an electronic device, such as a radio telescope detector. The term refers to either a wavelength interval or a frequency interval.

Bandwidth, from → band + → width.

Bândpahnâ, from bând, → band, + pahnâ, → width, from pahn "wide," → broad.

broad-band photometry
  شیدسنجی ِ پهن-باند   
šidsanji-ye pahn-bând

Fr.: photométrie à bande large   

Photometric measurements carried out through filters with a band-width (about one-tenth the central wavelength) in the range 30-100 nm. Typical examples are Johnson photometry, Krons-Cousins RI photometry, and the six-color system.

broad; → band; → photometry.

conduction band
  باند ِ هازش   
bând-e hâzeš

Fr.: bande de conduction   

In the energy spectrum of a solid, a range of energies in which electrons can move freely under the influence of an electrical field. Metals have many electrons in this range, insulators have none. In semiconductors the conduction band contains few electrons provided by impurity atoms or ejected from the valence bands by thermal energy or photon absorption.

conduction; → bande.

cyanogen band
  باند ِ سیانوژن   
bând-e siyânožen (#)

Fr.: bande de cyanogène   

An → absorption band of molecular origin characterizing the spectra of → late-type stars (G0 and later, e.g. → S star). → Cyanogen absorption is an important → luminosity criterion for → low-mass stars, and is more pronounced in → giant stars than in → dwarf stars of the same → spectral type.

cyanogen; → band.

diffuse interstellar band (DIB)
  باند ِ پخشیده‌ی ِ اندر‌اختری   
bând-e paxšide-ye andaraxtari

Fr.: bande diffuse interstellaire   

Absorption features in the spectrum of stars identified in the ultraviolet, visible, and infrared regions. They have an interstellar origin, but despite extensive efforts, their carrier(s) have not yet been clearly identified. See also → Aromatic Infrared Bands; → polycyclic aromatic hydrocarbons.

diffuse; → interstellar; → band.

diffuse interstellar band carrier
  برنده‌ی ِ باند ِ پخشیده‌ی ِ اندر‌اختری   
barande-ye bând-e paxšide-ye andaraxtari

Fr.: porteur des bandes diffuses interstellaires   

The chemical element or composition that is supposedly at the origin of a → diffuse interstellar band (DIB).

diffuse; → interstellar; → band; → carrier.

emission band
  باند ِ گسیلی   
bând-e gosili

Fr.: bande d'émission   

In a spectrum, a combination of several closely spaced, often unresolved, → emission lines occurring across a limited range of wavelengths.

emission; → band.

forbidden band
  باند ِ بژکم   
bând-e bažkam

Fr.: bande interdite   

In → solid state physics, a range of → energy levels which is not attained by any electrons in a → crystal. In the energy level diagram forbidden bands appear as gaps between → allowed bands.

forbidden; → band .

frequency band
  باند ِ بسامد   
bând-e basâmad

Fr.: bande de fréquence   

A range of frequencies that is continuous between two specified limits, selected from a more extended range of frequencies.

frequency; → band.

G band
  باند ِ G   
bând-e G

Fr.: bande G   

A conspicuous band of molecular → CH (methylidine) at 4300 Å, which is present in the spectra of late-type G-K stars.

G refers to → G type stars in the spectra of which this feature is strong. → band.

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