Accession Number : ADA019656

Title :   The Calculation of Riometer Absorption and an Approximation Connection between Riometer Absorption and Solar Proton Fluxes during Nighttime PCA Events.

Descriptive Note : Environmental research papers,

Corporate Author : AIR FORCE CAMBRIDGE RESEARCH LABS HANSCOM AFB MASS

Personal Author(s) : Stroscio,Michael A. ; Sellers,Bach

Report Date : 05 SEP 1975

Pagination or Media Count : 39

Abstract : In this report, the calculation of riometer absorption during several PCA events of particular interest is presented. These calculations are based on earlier work in which an improved effective recombination coefficient was derived and an atmospheric model for (1) each month of the year, (2) day and night, and (3) 60 deg N and 90 deg N latitude was presented. In this report, the calculated values of riometer absorption are presented for 5 PCA events: 2 Nov. 69, 7 Mar. 70, 25 Jan. 71, 2 Sep. 71, and 3 Aug. 72. The calculated values of riometer absorption are compared with experimental values measured for both day and night conditions at Thule, Greenland. An approximate connection between riometer absorption and the square-root of the proton flux for nighttime conditions is presented. This relationship, which has previously been applied only for daytime conditions, is discussed both on a fundamental level and on the level of verification by comparison with experiment. In addition, the basic equation widely used to calculate riometer absorption is compared with the original Sen-Wyller result.

Descriptors :   *Polar cap absorption, *Riometers, Absorption coefficients, Protons, Solar cosmic rays, Particle flux, Recombination reactions, Night, Atmospheric physics, Mathematical models, Atmosphere models, Transport properties, Diurnal variations, Computer programs, Ionosphere, Experimental data, Greenland, Day

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE