An Etymological Dictionary of Astronomy and Astrophysics
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فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 8 Search : dense
condense
  چگالیدن   
cagâlidan (#)

Fr.: condenser   

General: (v.tr.) To reduce the volume of, to make more concise. (v.intr.) To become more compact, to undergo condensation.
Physics: To cause a gas or vapor to change to a liquid. To remove water from a substance.

L. condensare "to make dense," from → com- intensive prefix + densare "make thick," from densus, → dense.

Cagâlidan from cagâl "dense, thick," of unknown etymology, + -idan infinitive suffix.

condensed
  چگالیده   
cagâlidé (#)

Fr.: condensé   

Relating to or produced by → condensation.

Adj. from → condense.

condensed matter
  ماده‌ی ِ چگالیده   
mâdeh-ye cagâlidé (#)

Fr.: matière condensée   

Matter in the liquid or solid state.

condensed; → matter.

dense
  چگال   
cagâl (#)

Fr.: dense   

Having relatively high → density.
Math.: The quality of a subset A of a topological space X, indicating that any point in X can be well approximated by points in A.

From L. densus "thick, crowded," cognate with Gk. dasys "hairy, bushy, thick grown."

Cagâl "dense, thick," related to ceqer "stiff, hard, tough, firm" (dialectal Kermâni ceqel, Šândizi caqal), caqâlé "stiff, unripe fruit."

dense core
  مغزه‌ی ِ چگال   
maqze-ye xagâl

Fr.: coeur dense   

An opaque region of a → molecular cloud (AV  10 mag) which is considered to be the progenitor of → star formation. Dense cores have temperatures of about 10 K and masses of roughly 1 to 10Msun each and in which the → molecular hydrogen density is roughly 104-105 cm-3 and size 0.1 pc. The → self-gravity of a dense core plays a central part in star formation. See also → hot molecular core.

dense; → core.

dense core mass function
  کریای ِ جرم ِ مغزه‌ی ِ چگال   
karyâ-ye jerm-e maqze-ye cagâl

Fr.: fonction de masse des cœurs denses   

core mass function.

dense; → core; → mass; → function.

dense molecular cloud
  ابر ِ مولکولی ِ چگال   
abr-e molekuli-ye cagâl

Fr.: nuage moléculaire dense   

A type of → interstellar medium cloud in which → carbon (C) becomes almost completely molecular due to relatively high → extinction. The chemistry is qualitatively different from that of → diffuse molecular clouds, as the → electron abundance is very low (→ cosmic-ray ionization being the dominant source) and the reactive C is replaced by the very stable → carbon monoxide (CO). This regime is found only in → sightlines with AV > 5-10 mag; not all such sightlines will contain dense cloud material and if dense cloud material is present it is likely to be surrounded by → translucent material. These clouds are typically → self-gravitating, and are most often observed by → infrared absorption and → millimeter wave emission methods. Their densities are typically at least 104 cm-3, and their → kinetic temperatures are typically on the order of 10-50 K in the quiescent regions. Most of the more than 140 currently known → interstellar molecules were found through observations of → microwaverotational transitions in such clouds, starting with the discovery of OH, followed by a host of other new detections such as CO, NH3, H2O, and H2CO (Snow & McCall, 2006, ARA&A 44, 367).

dense; → molecular; → cloud.

overdense matter
  ماده‌یِ بیش‌چگال   
mâdde-ye biš-cagâl

Fr.: matière surdense   

Matter whose density exceeds a reference level.

over-; → dense; → matter.