An Etymological Dictionary of Astronomy and Astrophysics

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory



<< < abs ann con deg exc gen hie int mic ove reg tem > >>

Number of Results: 233 Search : era

Fr.: surabondance   

The abundance of a chemical element exceeding a reference value, in particular compared to that of the Sun.

over-; → abundance.


Fr.: patera   

A shallow dish-like crater with irregular, sometimes scalloped rims, on the surface of a planet.

From L. patera "abroad, shallow dish" (used for drinking, primarily in a ritual context).

performative utterance
  واپش ِ پرگالنده   
vâpeš-e pergâlandé

Fr.: performativité   

A sentence or expression which is not only describing a given reality, but actually does or accomplishes something. For example "I now declare you husband and wife" (when uttered by the authorized officiator during a marriage ceremony).

performative; → utterance.


Fr.: périphérique   

Pertaining to, situated in, or constituting the periphery.

Adj. of → periphery.

peripheral response
  پاسخ ِ پیرابَری   
pâsox-e pirâbari

Fr.: réponse périphérique   

In a charge-coupled device, the detection of charge collected by the transport register rather than by the image-sensing elements.

peripheral; → response.

peripheral vision
  دید ِ پیرابَری   
did-e pirâbari

Fr.: vision périphérique   

In optics, the ability to see over large angles of view.

peripheral; → vision.

Planck era
  دوران ِ پلانک   
dowrân-e Planck

Fr.: ère de Planck   

The first 10-43 seconds of the Universe's existence, when the size of the Universe was roughly the Planck length and during which quantum effects of gravity were significant. Also called Planck epoch. Our understanding of the Planck era is poor because theory which encompasses both quantum mechanics and general relativity is needed to be developed.

Planck; → era.

pre-degenerate star
  ستاره‌ی ِ پیش-واگن   
setâre-ye piš-vâgen

Fr.: étoile pré-dégénérée   

Same as → PG 1159 star.

post-; → degenerate; → star.


Fr.: préférable   

Worthy to be preferred; more desirable.

prefer; → -able.

proton temperature
  دمای ِ پروتونی   
damâ-ye protoni

Fr.: température protonique   

The temperature in the → solar wind, as derived from the mean kinetic energy of protons: mv2/2 = (3/2)kTp, where k is → Boltzmann's constant. There are two types of proton temperature: parallel temperature, measured from protons moving parallel to the magnetic field, and perpendicular temperature relating to protons at right angles to the magnetic field. The proton temperature is usually derived using particle detectors on board space probes that determine the velocity → distribution function of the particles from their energies (N. Meyer-Vernet, 2007, Basics of the Solar Wind, Cambridge Univ. Press). See also → electron temperature.

proton; → temperature.

  چهاربر، چاربر   
cahârbar (#), cârbar(#)

Fr.: quadrilatère   

A plane figure bounded by four straight lines.

From L. quadrilater(us) "four-sided," from L. quattuor, → four, + → lateral.

quantum-mechanical operator
  آپارگر ِ مکانیک ِ کو‌آنتومی   
âpârgar-e mekânik-e kuântomi

Fr.: opérateur en mécanique quantique   

A linear → Hermitian operator associated with a physical quantity.

quantum; → mechanics; → operator.

radiation era
  دوران ِ تابش   
dowrân-e tâbeš

Fr.: ère du rayonnement   

The epoch in the history of the Universe, lasting from the → Big Bang until about 400,000 years later, when the temperature had dropped to 109 K and the rate of electron-positron → pair annihilation exceeded the rate of their production, leaving radiation the dominant constituent of the Universe. The radiation era was followed by the → matter era.

radiation; → era.

radiation temperature
  دمای ِ تابش   
damâ-ye tâbeš

Fr.: température de rayonnement   

The temperature of a source calculated assuming that it behaves as a → blackbody that radiates with the same intensity at the same frequency. Compared to the → effective temperature, the radiation temperature is measured over a narrow region of the → electromagnetic spectrum.

radiation; → temperature.

radiative acceleration
  شتاب ِ تابشی   
šetâb-e tâbeši

Fr.: accélération radiative   

The acceleration imparted to matter by → radiation pressure.

radiative; → acceleration.

real-time operation
  آپارش در زمان ِ هسیا   
âpâreš dar zamân-e hasyâ

Fr.: opération en temps réel   

The operation of a computer during the actual time that the related physical processes take place so that the results can be used to guide the physical processes.

real; → time; → operation.

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.


Fr.: regénérer   

1) To produce anew; bring into existence again; to bring new and more vigorous.
2) Biology: To renew or restore (a lost, removed, or injured part).
3) Physics: To restore (a substance) to a favorable state or physical condition.
4) Electronics: To magnify the amplification of, by relaying part of the output circuit power into the input circuit (

re-; → generate.


Fr.: regénération   

1) Act of regenerating; state of being regenerated.
2) Electronics: A feedback process in which energy from the output of an amplifier is fed back to the grid circuit to reinforce the input.
3) Biology: The restoration or new growth by an organism of organs, tissues, etc., that have been lost, removed, or injured (

re-; → generation.

  باز-آزاننده، باز-آزانشی   
bâz-âzânandé, bâz-âzâneši

Fr.: régénératif   

1) Of, relating to, or characterized by regeneration.
2) Tending to regenerate.

re-; → generative.

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