XUV electron density diagnostics for solar flares

Journal Article · Fri Jun 01 04:00:00 EDT 1979 · Astrophys. J., Suppl. Ser.; (United States)

DOI:https://doi.org/10.1086/190590· OSTI ID:5929531

Dere, K P; Mason, H E; Widing, K G; Bhatia, A K

An extensive study has been carried out of potential electron density diagnostics for the high-temperature component (>5 x 10/sup 5/K) of solar flares. The wavelength region considered is that covered by the Naval Research Laboratory's XUV spectroheliograph aboard Skylab (171--630A). The ions studied are Fe IX through Fe XV; Ni XI; through Ni XVII; and members of the beryllium, boron, carbon, and nitrogen isoelectronic sequences. We discuss theoretical intensity ratios for lines which are dependent on electron density in the range 10/sup 9/ to 10/sup 12/ cm/sup -3/. These results are used to analyze spectra from the 1973 August 9 and 1973 December 17 flares. For these flares we find that the electron density rises from 10/sup 10/ to 5 x 10/sup 11/ cm/sup -3/ for the temperature rise of 10/sup 6/ to 10/sup 7/ K. New atomic data for Ar XIV, Ca XVI, Ar XIII, and Ca XV are listed in the Appendix.

• Research Organization: E. O. Hulburt Center for Space Research
• OSTI ID: 5929531
• Journal Information: Astrophys. J., Suppl. Ser.; (United States), Journal Name: Astrophys. J., Suppl. Ser.; (United States) Vol. 40:2; ISSN APJSA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATOMS
CHARGED PARTICLES
ELECTROMAGNETIC RADIATION
ELECTRON DENSITY
ELECTRONIC STRUCTURE
EMISSIVITY
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXTREME ULTRAVIOLET RADIATION
IONS
ISOELECTRONIC ATOMS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RADIATIONS
SOLAR ACTIVITY
SOLAR FLARES
SPECTRA
SURFACE PROPERTIES
ULTRAVIOLET RADIATION
ULTRAVIOLET SPECTRA