2800 MHz SOLAR FLUX The sun emits radio energy with a slowly varying intensity. This radio flux,which originates from atmospheric layers high in the sun's hromosphere and low in its corona, changes gradually from day-to-day, in response to the number of spot groups on the disk. Radio intensity levels consist of emission from three sources: from the undisturbed solar surface, from developing active regions, and from short-lived enhancements above the daily level. Solar flux density at 2800 megaHertz has been recorded routinely by radio telescope near Ottawa since February 14, 1947. Each day, levels are determined at local noon (1700 GMT) and then corrected to within a few percent for factors such as antenna gain,atmospheric absorption, bursts in progress, and background sky temperature.Beginning in June 1991, the solar flux density measurement source is Penticton, B.C., Canada. The tables contain fluxes from the entire solar disk at a frequency of 2800 megaHertz in units of 10 to the -22 Joules/second/square meter/Hertz. Each number has been multiplied by 10 to suppress the decimal point. Three sets of fluxes--the observed, the adjusted, and the absolute--are summarized. Of the three, the observed numbers are the least refined, since they contain fluctuations as large as 7% that arise from the changing sun-earth distance. In contrast, adjusted fluxes have this variation removed; the numbers in these tables equal the energy flux received by a detector located at the mean distance between sun and earth. Finally, the absolute levels carry the error reduction one step further; here each adjusted value is multiplied by 0.90 to compensate for uncertainties in antenna gain and in waves reflected from the ground. NOTE: The 1992.adj, 1992.abs, monthly.adj, monthly.abs, monthplt.adj, and monthplt.abs were all changed with corrected Dec 1992 data on 2 Mar 95. We included a utility program to transform the tabular data to a plot format. The program name is XY_PAIRS.EXE. Use the following directions to make a plot file from the tabular data: Run the program 'XY_PAIRS.EXE' Input file: File to convert to plot (xy) format: 1950.OBS Output file: 1950OBS.PLT Year: Give the year of the file: 1950 Answer the last question no: N The output file (1950OBS.PLT) will look like this: 1950 01 01 1324 1950 01 02 --- 1950 01 03 1351 1950 01 04 1306 Missing data will be represented as ---. The data are displayed as the flux value multiplied by ten (same as the table format). For example, 1324 converts to 132.4 solar flux units for Jan 1, 1950. * After the data indicates corrected for burst in progress. E = corrected for snow on antenna