Observations of H. cap alpha. and microwave brightening caused by a distant solar flare

Journal Article · Tue Feb 15 04:00:00 EST 1983 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/160750· OSTI ID:6268978

Kundu, M R; Rust, D M; Bobrowsky, M

Three subflares were observed at 6 cm lambda and at H ..cap alpha.. (6563 A) with the NRAO Very Large Array (VLA) and the Solar Observing Optical Network (SOON) high resolution telescopes. Synthesized maps with integration times of 10 and 30 s show that most of the 6 cm burst emission originated in approx. 10''-15'' features coincident with or adjacent to H ..cap alpha.. flare kernels. The brightness temperatures of the radio features ranged from 3 x 10/sup 7/ to 9 x 10/sup 7/ K. During the onset of one of the subflares 6 cm emission was discovered in a loop stretching>10/sup 5/ km from the pirmary flare site; this emission was associated with faint H..cap alpha.. flarelike brightness at the remote footpoint of the loop. Assuming that the energy for the distant brightening originated at the primary flare site, we find that approx.4 x 10/sup 24/ ergs s/sup -1/ propagated along the connecting magnetic loop at a velocity of > or =6000 km s/sup -1/. We discuss various possible mechanisms for the distant activation. We rule out MHD shocks and thermal conduction fronts as the exciting agents. We suggest that the energy may have been carried by electrons originating in the high energy tail of the electron thermal velocity distribution and escaping from the primary flare site.

• Research Organization: Astronomy Program, University of Maryland
• OSTI ID: 6268978
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 265:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BALMER LINES
ELECTROMAGNETIC RADIATION
ELECTRONS
ELEMENTARY PARTICLES
EMISSION SPECTRA
FERMIONS
INTERFEROMETRY
LEPTONS
RADIATIONS
RADIOWAVE RADIATION
SOLAR ACTIVITY
SOLAR ELECTRONS
SOLAR FLARES
SOLAR PARTICLES
SOLAR RADIATION
SOLAR RADIO BURSTS
SOLAR RADIOWAVE RADIATION
SPECTRA
STELLAR RADIATION