Temporal correlations between impulsive ultraviolet and hard X-ray bursts in solar flares observed with high time resolution

Journal Article · Fri Jul 01 04:00:00 EDT 1988 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/166486· OSTI ID:6833381

Cheng, C C; Vanderveen, K; Orwig, L E; Tandberg-Hanssen, E

The impulsive phase of solar flares has been simultaneously observed in the ultraviolet O V line, the UV continuum, and hard X-rays with a time resolution of 0.128 s by the SMM satellite. A close time correspondence between the three impulsive components is found, with the best correlation being at the peak of the impulsive phase. Individual bursts or fast features in the O V and the UV continuum are shown to lag behind the corresponding hard X-ray features. None of the considered energy transport mechanisms (thermal conduction, a nonthermal electron beam, electron hole boring, UV radiation, and Alfven waves) are able to consistently account for the observed temporal correlations. 30 references.

• Research Organization: E. O. Hulburt Center for Space Research, Washington, DC (UAS); California Institute of Technology, Pasadena (USA); NASA, Goddard Space Flight Center, Greenbelt, MD (USA); NASA, Marshall Space Flight Center, Huntsville, AL (USA)
• OSTI ID: 6833381
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 330; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALFVEN WAVES
BEAMS
ELECTROMAGNETIC RADIATION
ELECTRON BEAMS
ENERGY TRANSFER
HARD X RADIATION
HYDROMAGNETIC WAVES
IONIZING RADIATIONS
LEPTON BEAMS
PARTICLE BEAMS
PHYSICAL PROPERTIES
RADIATIONS
SATELLITES
SOLAR ACTIVITY
SOLAR FLARES
THERMAL CONDUCTIVITY
THERMODYNAMIC PROPERTIES
ULTRAVIOLET RADIATION
X RADIATION