EUV continua of solar flares 1420--1960 A

Journal Article · Mon Jan 15 04:00:00 EST 1979 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/156775· OSTI ID:6470037

Cook, J W; Brueckner, G E

Measurements of absolute continuum intensities in the wavelength range 1420--1960 A are presented for the SN subflare of 1973 August 9 and the 2B flare of 1973 September 7, observed from the NRL spectrograph aboard Skylab. We also give continuum measurements for two active-region plages, which are used for background nonflaring levels. Major enhancement of the flare continuum intensity above the plage backgrounds occurs in the Si I /sup 3/P and /sup 1/D continua. The observed brightness-temperature minimum of the plages is approximately 310 K above the quiet-Sun minimum, and occurs at longer wavelength. The earliest flare brightness-temperature minima are approximately 200 K above the plage minimum, and also at longer wavelength. The observed decay time of the flare brightness temperature, which is comparable to the Solrad 9 X-ray decay time, is much longer than the Ulmschneider radiative relaxation time for the 1973 September 7 flare and marginally longer for the 1973 August 9 flare, suggesting continuous excess heating of the plage temperature minimum region throughout the period of our flare observations.

• Research Organization: E. O. Hulburt Center for Space Research, Naval Research Laboratory
• OSTI ID: 6470037
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 227:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DATA
DATA FORMS
EXPERIMENTAL DATA
INFORMATION
ISOLATED VALUES
NUMERICAL DATA
PLAGES
SOLAR ACTIVITY
SOLAR FLARES
SPECTRA
SPECTROSCOPY
ULTRAVIOLET SPECTRA