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

Device that produces an observable image that is brighter at output than the image at input.

→ image; → intensifier.

The plane in which is formed an image produced by an → optical system.

→ image; → plane.

One of the points constituting an extended image formed in an → optical system.

→ image; → point.

The use of techniques to produce, extract, identify, and display images for evaluation, interpretation, and further interaction with the data.

→ image; → processing.

1) The degree of visibility of relevant → information in an image.
2) The → full-width at half-maximum of a long exposure stellar image obtained by an instrument mounted on a telescope observing in the presence of → seeing.

→ image; → quality.

The separation between two detached but adjacent points in an image.

→ image; → resolution.

The process by virtue of which the original image can be created by removing the blurring and the noise that occur during image formation.

→ image; → restoration.

The quantity that relates the length on the image to the angular or physical separations on the sky.

→ image; → scale.

In an → optical system, the space defined by the totality of → image points. The corresponding points in image space and → object space are called → conjugate points.

→ image; → space.

A device for amplifying faint images by electronic means. Electrons, released when the incident radiation forms a pattern on a photocathode, are accelerated by a magnetic field so that they form a second, brighter image when they strike a phosphor screen.

→ image; → tube.

An electronic device which records images.

→ image; → -er.

1) The formation of mental images, figures, or likenesses of things, or of such images collectively.
2) Pictorial images, as in works of art (Dictionary.com).

Noun from → imager.

Capable of being imagined or conceived.

→ imagine; → -able.

1) Existing only in the imagination.
2) Math.: → imaginary number.

→ imagine; → -ary.

A number that is or can be expressed as the square root of a negative number; thus √ -1 is an imaginary number, denoted by i; i² = - 1.

→ imaginary; → number.

1) The faculty of imagining, or of forming mental images or concepts of what is not actually present to the senses.
2) The action or process of forming such images or concepts (Dictionary.com).

→ imagine; → -tion.

Characterized by or bearing evidence of imagination (Dictionary.com).

→ imagination; → -ive.

1) To form a mental image of (something not actually present to the senses).
2) To think, believe, or fancy.
3) To assume; suppose.
4) To conjecture; guess (Dictionary.com).

M.E. imaginen, from M.Fr. imaginer "sculpt, carve, paint; decorate," from L. imaginari "to form a mental picture, picture to oneself, imagine," from imago "an image, a likeness," from stem of imitari "to copy, imitate" (from PIE root *aim- "to copy").

Vinârdan, from vin, short for vine, → image, + ârdan, short for âvardan "to bring; to cause, produce" (Mid.Pers. âwurtan, âvaritan; Av. ābar- "to bring; to possess," from prefix ā- + Av./O.Pers. bar- "to bear, carry," bareθre "to bear (infinitive)," bareθri "a female that bears (children), a mother;" Mod.Pers. bordan "to carry;" Skt. bharati "he carries;" Gk. pherein; L. fero "to carry").

The visual representation of an astronomical body using a two-dimensional detector and computerized techniques.

From → image + → -ing.

Tasvirgari, from tasvirgar agent noun from tasvir→ image + -gar from kar-, kardan "to do, to make" (Mid.Pers. kardan; O.Pers./Av. kar- "to do, make, build;" Av. kərənaoiti "makes;" cf. Skt. kr- "to do, to make;" krnoti "makes," karma "act, deed;" PIE base k^wer- "to do, to make").

The method used to detect very brief flashes of → Cherenkov radiation generated by the → cascade shower of → relativistic charged particles produced when a very high-energy → gamma ray (in the range 50 GeV to 50 TeV) strikes the atmosphere at a typical altitude of 10 km. Owing to this technique, it possible to discriminate cosmic gamma rays from the cosmic ray background and to determine their energy and source direction. More specifically, the incoming gamma-ray photon undergoes → pair production in the vicinity of the nucleus of an atmospheric molecule. The electron-positron pairs produced are of extremely high energy and immediately radiate in a → bremsstrahlung process. This radiation is itself extremely energetic, with many of the photons undergoing further pair production. A cascade of charged particles ensues which, due to its extreme energy, produces a flash of Cherenkov radiation lasting between 5 and 20 nano-seconds. The total area on the ground illuminated by this flash corresponds to many hundreds of square meters, which is why the effective area of IACT telescopes should be large.

→ imaging; → atmospheric; → Cherenkov; → technique.