An Etymological Dictionary of Astronomy and Astrophysics
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An → elliptical galaxy whose → surface brightness can be approximated by a single → power law at small radii (r ≤ 10-20''). More modern interpretations have emphasized that these profiles can be better understood as the inward continuation of the galaxy's overall → Sersic profile, usually modified by an additional, nuclear-scale stellar component (S. P. Rusli et al., 2013, AJ 146, 160).

→ power; → law; → galaxy.

A measure of an optical system's ability to produce an image which separates two points or parallel lines on the object.

Resolving verbal adj. of → resolve; → power.

A → neutron star that is spinning down as a result of → torques from → magnetic dipole radiation and particle emission. RPPs derive their energy primarily from the → rotation of the neutron star. The energy from their → spin-down appears as broad-band pulsations from → radio to → gamma-ray wavelengths and as a → wind of energetic particles flowing into their surrounding → pulsar wind nebulae. Since the discovery of RPPs through their radio → pulsations in 1967, more than 2000 → radio pulsars are now known with periods ranging from a few milliseconds to several seconds (A. K. Harding, 2013, Front. Phys. 8, 679).

→ rotation; → power; → pulsar.

Any power obtained by converting solar radiation into useful power.

→ solar; → power.

The → sound energy emitted by a source per unit time, usually expressed in → watts. Sound power causes → sound pressure.

→ sound; → power.

The sound energy emitted by a sound source per unit time and expressed in → decibels. Sound power, in → watts, is converted to sound power level in decibels (L), by L = 10 log (W/W₀), where W₀ is the reference power (1 x 10 ^-12 watt).

→ sound; → power; → level.

A quantity indicating the extent with which a substance absorbs a → charged particle passing through it. It is the energy lost by a → non-relativistic particle per unit length of its path in the substance.

→ stop; → power.