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

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

   Homepage   
   


A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

<< < -es -iv -ti 21- a p abe abs abs acc acc acc act act ada adi ads aes Age Alb Alf ali all alp alt ama amp ana ang ang ann ano ant ant ape apo app app arc Arg ari art ass ast ast ast atm ato att Aur aut axi azi bac Bal Bar Bar Bay Bec Ber bet bic bij bin bio Bir bla Bla blu blu bol Boo bou bra Bre bro bug C r cal Cal can car Car Cas cat cau cel cen cer Cha cha Cha che chl cir cir cir Cla cli clo clu co- coc coh col col col com com com com com com com com Com con con con con con con con con con con con con Cop Cor cor cor cos cos Cou cou cow cre cri cro cry cur cut Cyg dam dar dat de deb dec dec ded def deg del dem den dep des det dev dia dif dif dig dio Dir dis dis dis dis dis dis div don dou dow dro dur dwa dyn Dys ear ebb ecl edg egg Ein Ela ele ele ele ele ell eme emp enc eng ent epi equ equ Equ esc eth Eur eve exa exc exe exi exp exp ext ext eye fac fal Far fed fer fer fie fin fir fit fla flo flu fol for for Fou fra fre Fre fro fuz gai Gal Gal gam gas Gau gen gen geo geo geo gia glo gol gra gra gra gra gre gri gui H I hai Ham har Hau hea hec hel hel her HES hie hig his hom hor hot Hub hum Huy hyd hyd hyl hyp ice ide ima imm imp imp inc ind ind ine inf inf Inf inh inn ins ins int int int int Int int int int inv ion iri irr iso iso iso Jea Jor jun K s Kep keV kin Kol lad Lam lan lar las lat lea leg len lev lig lik lin lin lin Lis lob loc log loo low lum lun lun Lym Mac Mag mag mag mag mag Mag mak map Mar mas mat Mau mea mea med Men mer Mes met met mho mic Mie Mil min mis MK mod mol mon moo mot mul mul mut nak Nas nat neb neg neu neu New New nip noi non non noo Nor nuc nuc nul nut obj obl obs occ oct off old one ope opp opt opt orb ord org Ori osc oth ove oxi P-w pal par par par par Pas pat pej per per per per per per pha Phi pho pho pho phy pin Pla pla pla pla pla plu poi pol pol pol poo pos pos pot pra pre pre pre pre pri pri pro pro pro pro pro Pro pro pse pul pur qua qua qua qua que rac rad rad rad rad rad rad ran rar ray rea rea rec rec red red ref ref reg rel rel rel ren res res res res ret rev Ric rig rin roc roo rot rot Rus Sac sal sat sca sca Sch sci Scu sec sec Sed sel Sel sen ser sex Sha she sho sid sig sil sim sin siz sle SMA SNR Sof sol sol sol sol sou Sou spa Sp spe spe spe sph spi Spi spr sta sta sta sta sta ste ste Ste sto str str sub sub sub suf sun sup sup sup sup sur swo syn sys tak Tay Tel ten ter tet the the the thi Tho thu tid tim toa top tot tra tra tra tra tri tri tro Tru tur twi Typ UBV ult unb uni uni Uni Unu ura uti val vap vec Vel ver Ver vie vir vis vis vol W-R war wav wav wea wei Whe Wid win WN4 Wol X-p Yal you zep zir > >>

Number of Results: 12992 Search : far
photographic survey
  بردید ِ عکسبرداریک   
bardid-e aksbardârik

Fr.: relevé photographique   

Recording a large area of the night sky by photographic techniques, as practiced in the past before the advent of electronic detectors.

Adj. of → photography; → survey.

photography
  عکسبرداری، شید-نگاری، نور-نگاری   
aksbardâri, šidnegâri, nurnegâri

Fr.: photographie   

The process of recording and producing images by exposing light-sensitive detectors to light or other forms of radiation.

photo-, → -graphy.

Aksbardâri, literally "taking photograph," from aks, → photograph, + bardâri verbal noun of bardâštan "to take," composite verb from bar- "on; up; upon; in; into; at; forth; with; near; before; according to" (Mid.Pers. abar; O.Pers. upariy "above; over, upon, according to;" Av. upairi "above, over," upairi.zəma- "located above the earth;" cf. Gk. hyper- "over, above;" L. super-; O.H.G. ubir "over;" PIE base *uper "over") + dâštan "to have, to possess" (Mid.Pers. dâštan; O.Pers./Av. root dar- "to hold, keep back, maintain, keep in mind;" cf. Skt. dhr-, dharma- "law;" Gk. thronos "elevated seat, throne;" L. firmus "firm, stable;" Lith. daryti "to make;" PIE *dher- "to hold, support").
Šidnegâri, nurnegâri, action noun from šidnegâr, nurnegâr, → photograph.

photoionization
  شید-یونش، نور-یونش   
šid-yoneš, nur-yoneš

Fr.: photoionisation   

The physical process in which an incident high-energy photon ejects one or more electrons from an atom, ion, or molecule.

photo- + → ionization.

photoionize
  شید-یونیدن، نور-یونیدن   
šid-yonidan, nur-yonidan

Fr.: photoioniser   

To cause, or to undergo → photoionization.

photo-; → ionize.

photoionized
  شید-یونیده، نور-یونیده   
šid-yonidé, nur-yonidé

Fr.: photoionisé   

Subject to, or produced by → photoionization.

photo-; → ionized.

photoluminescence
  شید-فروزستی   
šid-foruzesti

Fr.: photoluminescence   

A process in which → absorption of photons at → ultraviolet (UV) / → optical wavelengths is followed by → electronic transitions associated with the emission of longer wavelength optical and → near-IR photons. Photoluminescence has two types: → phosphorescence and → luminescence. The excitation of the photoluminescence process under astrophysical conditions results from the absorption of a single UV/optical photon, leading to an electronic transition from a → ground state (1) to a higher state (2). State (2) typically is a bound, high-lying vibrational-rotational level of the first or second electronically excited state of a molecule or molecular ion, or a high state in the → conduction band of a semiconductor particle. The excited system relaxes through a series of → vibrational-rotational transitions until the electron finds itself in an intermediate state (3), from where an optical electronic transition back to the ground state (1) is possible. In a → polycyclic aromatic hydrocarbon (PAH) molecule, for example, state (3) can either be the lowest state in the → singlet or → triplet vibrational-rotational manifold of the first excited electronic level (Witt, A. N., Vijh, U. P., 2003, astro-ph/0309674).

photo-; → luminescence.

photometer
  شید-سنج، نور-سنج   
šidsanj, nursanj

Fr.: photomètre   

An instrument for measuring the amount of light.

photo- + → -metry.

photometric
  شید-سنجی، شید-سنجیک، نور-سنجی، نور-سنجیک   
šidsanji, šidsanjik, nursanji, nursanjik

Fr.: photométrique   

Pertaining to or related to → photometry.

photometer + → -ic.

photometric band
  باند ِ شیدسنجیک، ~ نورسنجیک   
bând-e šid-sanjik, ~ nur-sanjik

Fr.: bande photométrique   

The range of → wavelengths allowed by a → filter used in a → photometric system.

photometric + → band.

photometric binary
  دُرین ِ شید-سنجیک، ~ نور-سنجیک   
dorin-e šidsanjik, ~ nursanjik

Fr.: binaire photométrique   

A binary star whose binarity is detectable from its variability and light-curve that has certain specific characteristics.

photometric + → binary.

photometric calibration
  کبیزش ِ شید-سنجیک، ~ سنور-سنجیک   
kabizeš-e šidsanjik, ~ nursanjik

Fr.: calibration photométrique   

A calibration which converts the measured relative magnitudes into an absolute photometry.

photometric + → calibration.

photometric parallax
  دیدگشت ِ شیدسنجیک   
didgašt-e šidsanjik

Fr.: parallaxe photométrique   

A method of deriving the distance of a star using its → apparent magnitude and the → absolute magnitude inferred from its → spectral type.

This is a misnomer, because the method has nothing to do with parallax; → photometric; → parallax.

photometric system
  راژمان ِ شید-سنجیک، ~ نور-سنجیک   
râžmân-e šidsanjik, ~ nursanjik

Fr.: système photométrique   

A system of → magnitudes, each of them characterized by a set of well-defined → passbands (or → filters) with known → response curves. The system is defined by the values given for the → standard stars. See also:
AB magnitude system, → five-color system, → Stromgren system, → JHK system, → UBV system, → uvby system.

photometric; → system.

photometry
  شید-سنجی، نور-سنجی   
šidsanji, nursanji

Fr.: photométrie   

In astronomy, the measurement of the light of astronomical objects, generally in the visible or infrared bands, in which a wavelength band is normally specified.

photo- + → -metry.

photomultiplier
  شید-بستاگر، نور-بستاگر   
šid-bastâgar, nur-bastâgar

Fr.: photomultiplicateur   

Electronic tube which converts photons into electrons, multiplies the electrons via a series of electrodes, and produces a measurable current from a very small input signal.

photo- + → multiplier.

photon
  فوتون   
foton (#)

Fr.: photon   

The → quantum of the → electromagnetic field, which mediates the interaction between charged particles. It is the mass-less → boson with zero → electric charge, which propagates with the → speed of light in vacuum. The energy of a photon is connected to its → frequency ν, through the formula E = hν, where h is → Planck's constant.

From phot-, variant of → photo- before a vowel + → -on a suffix used in the names of subatomic particles (gluon; meson; neutron), quanta (photon, graviton), and other minimal entities or components. The term photon was coined by Gilbert N. Lewis in 1926 in a letter to the editor of Nature magazine (Vol. 118, Part 2, December 18, page 874).

photon escape time
  زمان ِ گریز ِ فوتون   
zamân-e goriz-e foton

Fr.: temps d'échappement des photons   

The time required for a photon created in the Sun's core to attain the → photosphere and leave the Sun. If the photons were free to escape, they would take a time of only R/c (a couple of seconds) to reach the surface, where R is the Solar radius and c the speed of light. The solar material is, however, very opaque, so that photons travel only a short distance before interacting with other particles. Therefore, photons undergo a very large number of → random walks before arriving at the surface by chance. The typical time is approximately 5 x 104 years for a constant density Sun.

photon; → escape; → time.

photon hardening
  سختش ِ فوتون   
saxteš-e foton

Fr.: durcissement des photons   

An effect occurring in the outer zones of → H II regions where the number of high-energy ultraviolet photons with energies well above the → ionization potential of hydrogen increases with respect to the number of → Lyman continuum photons. The effect is due to stronger absorption of weaker photons.

hard; → photon.

photon noise
  نوفه‌ی ِ فوتون   
nufe-ye foton

Fr.: bruit de photons   

An intrinsic noise caused by the quantum nature of light. Same as → quantum noise.

photon; → noise.

photon sphere
  سپهر ِ فوتون   
sepehr-e foton

Fr.: sphère de photons   

A surface where if a photon is emitted from one of its points the photon follows a closed orbit and returns periodically to its departure point. Such a surface exists only near sufficiently → compact objects where the → curvature of → space-time is very important. In other words, a body can take a stable orbit around a → black hole provided that it moves with the → speed of light. However, only photons can have such a velocity; hence the term "photon sphere." For a non-rotating → Schwarzschild black hole, the photon sphere has a radius of R = 3GM/c2 = 3 RS/2, where G is the → gravitational constant, M is the mass, c is the → speed of light, and RS is the → Schwarzschild radius. For a rotating, → Kerr black hole, the situation is much more complex due to the → Lense-Thirring effect. In that case circular paths exist for radii whose values depend on the rotation direction. More specifically, in the equatorial plane there are two possible circular light paths: a smaller one in the direction of the rotation, and a larger one in the opposite direction.

photon; → sphere.

<< < -es -iv -ti 21- a p abe abs abs acc acc acc act act ada adi ads aes Age Alb Alf ali all alp alt ama amp ana ang ang ann ano ant ant ape apo app app arc Arg ari art ass ast ast ast atm ato att Aur aut axi azi bac Bal Bar Bar Bay Bec Ber bet bic bij bin bio Bir bla Bla blu blu bol Boo bou bra Bre bro bug C r cal Cal can car Car Cas cat cau cel cen cer Cha cha Cha che chl cir cir cir Cla cli clo clu co- coc coh col col col com com com com com com com com Com con con con con con con con con con con con con Cop Cor cor cor cos cos Cou cou cow cre cri cro cry cur cut Cyg dam dar dat de deb dec dec ded def deg del dem den dep des det dev dia dif dif dig dio Dir dis dis dis dis dis dis div don dou dow dro dur dwa dyn Dys ear ebb ecl edg egg Ein Ela ele ele ele ele ell eme emp enc eng ent epi equ equ Equ esc eth Eur eve exa exc exe exi exp exp ext ext eye fac fal Far fed fer fer fie fin fir fit fla flo flu fol for for Fou fra fre Fre fro fuz gai Gal Gal gam gas Gau gen gen geo geo geo gia glo gol gra gra gra gra gre gri gui H I hai Ham har Hau hea hec hel hel her HES hie hig his hom hor hot Hub hum Huy hyd hyd hyl hyp ice ide ima imm imp imp inc ind ind ine inf inf Inf inh inn ins ins int int int int Int int int int inv ion iri irr iso iso iso Jea Jor jun K s Kep keV kin Kol lad Lam lan lar las lat lea leg len lev lig lik lin lin lin Lis lob loc log loo low lum lun lun Lym Mac Mag mag mag mag mag Mag mak map Mar mas mat Mau mea mea med Men mer Mes met met mho mic Mie Mil min mis MK mod mol mon moo mot mul mul mut nak Nas nat neb neg neu neu New New nip noi non non noo Nor nuc nuc nul nut obj obl obs occ oct off old one ope opp opt opt orb ord org Ori osc oth ove oxi P-w pal par par par par Pas pat pej per per per per per per pha Phi pho pho pho phy pin Pla pla pla pla pla plu poi pol pol pol poo pos pos pot pra pre pre pre pre pri pri pro pro pro pro pro Pro pro pse pul pur qua qua qua qua que rac rad rad rad rad rad rad ran rar ray rea rea rec rec red red ref ref reg rel rel rel ren res res res res ret rev Ric rig rin roc roo rot rot Rus Sac sal sat sca sca Sch sci Scu sec sec Sed sel Sel sen ser sex Sha she sho sid sig sil sim sin siz sle SMA SNR Sof sol sol sol sol sou Sou spa Sp spe spe spe sph spi Spi spr sta sta sta sta sta ste ste Ste sto str str sub sub sub suf sun sup sup sup sup sur swo syn sys tak Tay Tel ten ter tet the the the thi Tho thu tid tim toa top tot tra tra tra tra tri tri tro Tru tur twi Typ UBV ult unb uni uni Uni Unu ura uti val vap vec Vel ver Ver vie vir vis vis vol W-R war wav wav wea wei Whe Wid win WN4 Wol X-p Yal you zep zir > >>