Pulsar scintillations and the parameters of interstellar plasma irregularities

Interstellar plasma irregularities have two distinct characteristic scales: α0 = 3 x 1010 cm and α1 = 3 x 1013 cm. The α0 irregularities are responsible for the primary effect of pulsar scintillation at decimeter wavelengths, while those of scale α1 cause the long-term intensity variations of both pulsars and quasars in a narrow wavelength band near lambda = 1 m. Electron-density (N/sub e/) fluctuations of scale α0 have an rms amplitude equal to 0.07% of the mean N/sub e/; fluctuations in N/sub e/ of scale α1 have an rms amplitude approximately equal to the mean N/sub e/ itself