An Etymological Dictionary of Astronomy and Astrophysics
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An electrical circuit containing both capacitance and inductance in such a way that a certain periodic electric oscillation will reach maximum amplitude.

→ resonant; → circuit.

A nuclear reaction whose probability is enhanced at an energy corresponding to an energy level of one of the nuclei. → resonance capture.

Resonant, verbal adj. of → resonate; → reaction.

A process whereby stellar orbit relaxation can be dramatically enhanced in orbits in a nearly Keplerian star cluster close to a → massive black hole (MBH). This process can modify the angular momentum distribution and affect the interaction rates of the stars with the MBH more efficiently than non-resonant relaxation. In the standard relaxation picture, each encounter is random and uncorrelated, so stars undergo a random walk. Relaxation is driven by the diffusion of energy which then leads to angular momentum transfer. However, in a stellar cluster around a MBH, each star will be on a Keplerian orbit, which is a fixed ellipse in space. The orbits of two nearby stars will thus exert correlated torques on one another, which can lead to a direct resonant evolution of the angular momentum. Since resonant relaxation increases the rate of angular momentum scattering, stars reach highly eccentric orbits more rapidly where they can become → extreme mass ratio inspiral (EMRI)s (Rauch, K.P., Tremaine, S., 1996, arXiv:astro-ph/9603018; Gair J.R. et al. 2013, Living Rev. Relativity, 16, (2013), 7 http://www.livingreviews.org/lrr-2013-7, doi:10.12942/lrr-2013-7).

→ resonant; → relaxation.

The absorption and prompt re-emission of photons of a particular wavelength by an atom. In this process, a photon of exactly the right wavelength (i.e. energy) excites an electron in the atom from one energy level to another. The electron then drops back down to its original energy level more or less immediately, emitting a photon of almost identical energy to the one that was absorbed in the first place, but in some random direction. Resonant scattering applies only to line radiation, unlike other forms of scattering which are of continuous radiation (Oxford Dictionary of Astronomy, 2 ed.).

→ resonant; → scattering.

To produce or exhibit mechanical, electrical, or chemical resonance, or cause a system to produce or exhibit resonance.

Verbal form of → resonance.

The absorption of a material by a medium or system after having been released from absorption by that same medium or system. → absorption; → desorption; → sorption.

Verbal noun of resorb, from L. resorbere, from → re- + sorbere "to swallow, suck up."

Bâzšam, from bâz "again, back," → re-, + šam, variant of zšâm, as in âšâm, âšâmidan "to drink, to sip;" Av. šam- "to drink, sip, swallow;" Skt. cam, camati "to sip, dirink, lick up, absorb."

1) A source of supply, support, or aid, especially one that can be readily drawn upon when needed.
2) (often plural) A source of economic wealth, especially of a country (mineral, land, labour, etc.) or business enterprise (capital, equipment, personnel, etc.) (Dictionary.com).

From Fr. ressourse, from O.Fr. resourdre "to rally, raise again," from L. resurgere "rise again," → re-, + → source.

Bâzxan, from bâz-, → re-, + xan, → source.

The smallest detail that can be seen in an image. Same as → angular resolution.

→ spatial; → resolution.

The capacity of a spectrograph to separate two adjacent spectral lines. The theoretical spectral resolution depends on the grating dispersion, grating position, pixel size, collimator and camera focal length, and the entrance slit-width.

→ spectral; → resolution.

The measure of the ability of an observing system to clearly separate events in time. In other words, the shortest time interval that can be determined between two different events.

→ temporal hour; → resolution.

Same → temporal resolution.

→ time; → resolution.

Describing an image whose constituent or elementary parts are not resolved. → unresolved source.

→ un- + → resolved.

A source of radiation whose angular size is too small for details of its structure to be revealed.

→ unresolved; → source.

Any particle of unit spin, such as the W boson, the photon, or the rho meson.

→ vector; → meson.