power-law spectrum

power-law spectrum

A spectrum quantified in terms of a power law. A nonthermal continuum spectrum is usually expressed by the dependence of the flux density S on the frequency ν raised to a certain power, S ∝ ν–α, where α is the spectral index. The ubiquity of this power-law fit to the multiwavelength continuum spectrum of all active galactic nuclei is strong evidence for the emission to be powered by the same mechanism in all cases, such as an accreting black hole. Only such an engine is capable of scaling its energy output through several orders of magnitude in luminosity without changing its fundamental spectrum.
References in periodicals archive ?
Formation of a gap at different angles of inclination of prolate irregularities with respect to the external magnetic field for the power-law spectrum is considered for the first time.
Measurements of satellite's signal parameters passing through ionospheric layer and measurements aboard of satellite show that in F-region of the ionosphere irregularities have power-law spectrum with different spatial scales.
For p > 3 spatial power-law spectrum could be rewritten as:
Experimental investigations of Doppler frequency shift of ionospheric signal show that index of the power-law spectrum of electron density fluctuations is in the range of 3.
Formation of a gap in the SPS and evaluation of its double-humped shape for power-law spectrum of electron density fluctuations in non-magnetized plasma at different angle of inclination of prolate irregularities with respect to the external magnetic field is considered for the first time.
Cygnus X-1 exhibits two distinct spectral states: a "soft" state with an excess of low-energy X-rays, and a "hard" state denoted by a smooth power-law spectrum to the highest energies detectable.