An Etymological Dictionary of Astronomy and Astrophysics
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A → quantum phase transition during which the → bosons constituting a sufficiently cooled boson gas are all clustered in the → ground energy state. The phase transition results in a → Bose-Einstein condensate. This phenomenon occurs when the temperature becomes smaller than a critical value given by: T_c = (2πħ² / km)(n / 2.612)^2/3, where m is mass of each boson, ħ is the → reduced Planck's constant, k is → Boltzmann's constant, and n is the particle number density. When T  ≤  T_c, the → de Broglie wavelength of bosons becomes comparable to the distance between bosons.

→ boson; → Einstein; → condensation.

1) General: The act of making more dense or compact.
2) Physics: The physical process by which a vapor becomes a liquid; the opposite of → evaporation. → sublimation; → deposition.
3) Acoustics: The ratio of the instantaneous excess of density to the normal density at a point in a medium transmitting longitudinal sound waves. → rarefaction.
4) Chemistry: Chemical change in which two or more molecules react with the elimination of water or of some other simple substance.
5) Meteorology: Any process by which water vapor changes to dew, fog, or cloud.

Verbal noun from → condense; → -tion.

A tiny suspended particle in the → atmosphere around which → water vapor condenses to form → droplets. Condensation nuclei are usually less than about 0.001 mm in diameter and can be made of → ice, → salt, → dust, and other materials. The droplets that form can be liquid water or ice, depending on the surrounding temperature. When the number of these droplets is large enough, a cloud is visible.

→ condensation; → nucleus.

Change of vapor into liquid. It takes place when the pressure of the vapor becomes equal to the maximum vapor pressure of the liquid at that temperature.

→ condensation; → vapor.

A part of the → solar corona where the gas density and the temperature are higher than in its vicinity. The coronal condensations are visible on the solar limb, above → sunspot groups. Images in X-rays and those supplied by → coronagraphs in white light reveal that such condensations consist of structures in the form of nodes, underlining the corona magnetic field (M.S.: SDE).

→ coronal; → condensation.