Impulsive hard X-rays from solar flares

Thesis/Dissertation · Sat Dec 31 23:00:00 EST 1983

OSTI ID:5364264

Leach, J

Solar flares have been observed intensively for more than two decades at X-ray energies in excess of 10 kilovolts. A technique is developed for determining the physical arrangement of a solar flare during the impulsive phase, based upon a non-thermal model interpretation of the emitted hard X-rays. This technique allows accurate values to be obtained for the flare parameters, including those which describe the magnetic field structure and the beaming of the energetic electrons, parameters which have hitherto been mostly inaccessible. This technique follows the evolution of streaming energetic electrons within the flare structure. The evolution of the electron number distribution, which is primarily controlled by Coulomb collisions, is evaluated using a steady-state Fokker-Planck Equation. From the evaluated electron distribution the emitted bremsstrahlung X-rays are calculated. The power of this technique lies in the ability to correlate the characteristics of these hard X-rays with the values of the model parameters describing the flare.

• Research Organization: Stanford Univ., CA (USA)
• OSTI ID: 5364264
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BREMSSTRAHLUNG
DIFFERENTIAL EQUATIONS
DISTRIBUTION
ELECTROMAGNETIC RADIATION
ELECTRONS
ELEMENTARY PARTICLES
EQUATIONS
FERMIONS
FOKKER-PLANCK EQUATION
IONIZING RADIATIONS
LEPTONS
MAGNETIC FIELDS
PARTIAL DIFFERENTIAL EQUATIONS
RADIATIONS
SOLAR ACTIVITY
SOLAR FLARES
SPATIAL DISTRIBUTION
X RADIATION