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

A device that receives data in one form and converts it to another. → analog-to-digital converter.

→ convert; → -er.

Having a surface that is curved or rounded outward.

From M.Fr. convexe, from L. convexus "vaulted, arched," p.p. of convehere "to bring together," from → com- "together" + vehere "to bring" (cf. Skt. vah- "to carry, lead," vahitra "vehicle," Av. vazaiti "to lead," Mid.Pers. waz-, wazidan "to carry away," Gk. oxos "chariot," PIE base *wegh- "to go, carry, drive").

Kuž "humped," Mid.Pers. kôf "hill, mountain; hump" (Mod.Pers. kuh, "mountain"), kôfik "humpbacked," O.Pers. kaufa-, Av. kaofa- "mountain."

A lens that converges an incident beam of light to a focus.

→ convex; → lens.

A → spherical mirror with a reflecting surface curved outward, that is toward the object.

→ convex; → mirror.

A diverging lens having one surface convex and the opposite surface concave.

→ convex; → concave; → lens.

To move by argument or evidence to belief, agreement, consent, or a course of action (Dictionary.com).

From L. convincere "to overcome decisively," from the intensive prefix → com- + vincere "to conquer, overcome, defeat," from PIE root *weik- "to fight, conquer."

Paruxidan, from Parthian Mid.Pers. prywx- "to conquer, overcome," from prefix pari- + yux "yoke;" Av. yuj- "to harness, yoke," variants yuj, juh, jut, jot; Mid.Pers. jug, ayoxtan "to join, yoke;" Pers. (+*pari-) piruz, pêrôz "victorious," → yoke.

Capable of causing someone to believe that something is true or real (OxfordDictionaries.com).

→ convince; → -ing.

The act of convoking. The state of being convoked.

Verbal noun of → convoke.

To call together; summon to meet or assemble (Dictionary.com).

M.E., from M.Fr. convoquer, from L. convocare "to call together," from → con- "together," + vocare "to call," from vox, → voice.

Hamvacidan, from ham-, → com-, + vac "word," → voice, + -idan infinitive suffix.

1) A mathematical combination of two functions which involves multiplying the value of one function at a given point with the value of another function, the weighting function, for a displacement from that point and then integrating over all such displacements. The process is repeated for every point of the function. Convolution expresses how the shape of a function is altered by the other. In mathematical terms, the convolution of two functions f(x) and g(x) is defined by: f*g = ∫f(u)g(x - u) du, integral from -∞ to +∞.
2) Astro.: Convolution describes how an instrument, through its transfer function, affects an input signal. → deconvolution.

Verbal noun of → convolve.

A theorem stating that the → Fourier transform of the convolution of f(x) and g(x) is equal to the product of the Fourier transform of f(x) and g(x): F{f*g} = F{f}.F{g}.

→ convolution; → theorem.

1) To roll or wind together.
2) To bring about a → convolution.

From L. convolvere "to roll together," from → com- "together" + volvere "to roll, turn," PIE base *wel- "to turn, revolve;" cf. Skt. valati "he turns," ulba- "womb, vulva," Gk. eilyein "to roll, wrap, fold."

Hamâgiš, from ham- "together", → com-, + âgišidan "to entwine, to twist" (Dehxodâ), from Mid.Pers. gyš- "to bind, tie," hangyš- "to fasten to;" cf. Sogd. patigyš- "to imprison, confine;" Proto-Ir. *kaš- "to imprison" (Cheung 2007).

The act or state of coordinating or of being coordinated.

Verbal noun of → coordinate.

A chemical compound in which a group of atoms or ions are attached by a coordination bond to a usually metallic central atom or ion.

→ coordination; → compound.

Crystallography: The crystal structure of a → coordination compound.

→ coordination; → lattice.

1) Crystallography: The number of nearest neighbors of an atom or ion in a → crystal lattice. A large coordination number indicates that the structure is more closely packed.
2) Chemistry: The number of atoms, ions, or molecules surrounding a central atom or ion in a complex.

→ coordination; → number.

A general heading which covers a wide variety of complex views on → quantum theory. As the first and the founding interpretation of the → quantum mechanics, it was developed in the late 1920's mainly by the Danish physicist Niels Bohr, but also Werner Heisenberg, Max Born and other physicists who made important contributions to the overall understanding of this field. Bohr expressed himself on the subject at various meetings and later published several articles and comments, but he never wrote a systematic and complete version of his views. There is not a unique Copenhagen Interpretation but various more or less complete versions, the common denominator of which is mainly the work of Bohr. Among those opposed to the Copenhagen Interpretation have been Albert Einstein, Erwin Schrödinger, Louis de Broglie, Max Planck, David Bohm, Alfred Landé, Karl Popper, and Bertrand Russell. The Copenhagen Interpretation recognizes that the deterministic picture of the universe that works so well at the macroscopic level does not work for the world at the quantum level. The universe at the quantum level is predictable only in a statistical sense. This implies that we can never really know the nature of quantum phenomena. The four cornerstones of the Copenhagen Interpretation are: → wave-particle duality, the probability → wave function, the → uncertainty principle, and the significance of the → observer. The observer is of the utmost importance because he causes the reality to unfold in the way it does. The key feature of the Copenhagen Interpretation is a concept known as the → collapse of the wave function, for which there is no known physical explanation; see also → Schrodinger's cat.

Copenhagen, from Dan. København "merchant's port," from køber "merchant" ("buyer") + havn "port," from the fact that the originator and chief interpreter of this school was Niels Bohr whose headquarters was in Copenhagen; → interpretation.

The mass distribution of → pre-stellar cores in → star-forming regions. The CMF is usually represented by dN/dM = M^α, where dM is the mass interval, dN the number of cores in that interval, and α takes different values in different mass ranges. In the case of → low-mass stars, it is found that the CMF resembles the → Salpeter function, although deriving the masses and radii of pre-stellar cores is not straightforward. The observational similarity between the CMF and the → initial mass function (IMF) was first put forth by Motte et al. (1988, A&A, 336, 150), and since then many other samples of dense cores have been presented in this context. For example, Nutter & Ward-Thompson (2007, MNRAS 374, 1413), using SCUBA archive data of the Orion star-forming regions, showed that the CMF can be fitted to a three-part → power law consistent with the form of the stellar IMF. Recent results, obtained using observations by the → Herschel Satellite, confirm the similarity between the CMF and IMF with better statistics (Könyves et al. 2010, A&A, 518, L106; André et al. 2010, A&A, 518, L102). Moreover, these works show that the CMF has a → lognormal distribution (i.e. dN/dlog M follows a → Gaussian form against log M), as is the case for the IMF at low masses (below about 1 solar mass).

→ core; → mass; → function.

The apparent acceleration corresponding to the → Coriolis force. It is the acceleration which, when added to the acceleration of an object relative to a rotating → reference frame and to its → centrifugal acceleration, gives the acceleration of the object relative to a fixed reference frame. Coriolis acceleration equals 2ω x v, where ω is the → angular velocity of the rotating reference frame and v is the radial velocity of a particle relative to the center of the rotating reference frame.

→ Coriolis effect; → force.

1) The outermost atmosphere of the Sun immediately above the → chromosphere, which can be seen during a total Solar eclipse. It consists of hot (1-2 × 10⁶ K), extremely tenuous gas (about 10^-16 g cm^-3) extending for millions of kilometer from the Sun's surface.
2) Meteorology: A set of one or more colored rings of small radii, concentrically surrounding the disk of the Sun, Moon, or other luminary when veiled by a thin cloud.

L. corona "crown, garland," cf. Gk. korone "anything curved, kind of crown."

Tâj "crown," loanword in Arm. tag "crown," tagavor "king," Proto-Iranian *tâgâ-, maybe from PIE base *(s)teg- "to cover" (L. toga "a garment worn by male citizens in ancient Rome;" hurtâj, from hur, → sun, + tâj.