HR: 1330h
AN: SH12A-1153    [PDF]
TI: The Solar Soft X-ray Irradiance and its None-flare Variability
AU: * Neupert, W M
EM: werner.neupert@noaa.gov
AF: Space Environment Center/NOAA, 325 Broadway, Boulder, CO 80305 United States
AB: The interval from 1965 to 1970 represents a unique period of time during which full-disk solar soft X-ray spectral observations and broadband soft X-ray flux measurements were made concurrently. Bragg crystal spectrometers flown on sounding rockets and orbiting spacecrafts provided data on spectral distributions between 0.8 and 2.5 nm during non-flaring periods, but with rather uncertain flux calibrations, while simultaneous observations by the NRL Solrad series of ionization chambers provided broadband and instrumentally stable flux coverage. We have combined these two types of observations to obtain in-flight calibration of the crystal spectrometer data taken over a wide range of solar activity. The Chianti spectral program was used to derive solar spectra matching the emission line distributions observed by the spectrometers and these theoretical spectra (with derived continua) were applied to the Solrad ion chamber measurements to recalculate their sensitivities for actual spectral distributions rather than for the "gray body" radiation used originally. The resulting absolute integrated flux values were then applied to the spectrometer observations to obtain absolute fluxes in specific emission lines. Changes in individual line fluxes between 0.8 and 2.5 nm as a function of the 2800 Mhz (F10) radio flux have also been determined and will be presented.
DE: 7537 Solar and stellar variability
DE: 7538 Solar irradiance
DE: 7554 X rays, gamma rays, and neutrinos
DE: 7594 Instruments and techniques
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting