New component of hard X-rays in solar flares

Journal Article · Tue Dec 15 04:00:00 EST 1981 · Astrophys. J., Lett. Ed.; (United States)

DOI:https://doi.org/10.1086/183704· OSTI ID:5729331

Lin, R P; Schwartz, R A; Pelling, R M; Hurley, K C

We present high resolution (approx.1 keV FWHM) spectral measurements from 13 to 300 keV of a solar flare hard X-ray burst observed on 1980 June 27 by a balloon-borne array of cooled germanium planar detectors. At energies below approx.35 keV we identify a new component of solar flare hard X-rays. This component is characterized by an extremely steep spectrum which fits closely to that from a Maxwellian electron distribution with a maximum temperature of approx.34 x 10/sup 6/ K and an emission measure of 2.9 x 10/sup 48/ cm/sup -3/. This hot isothermal component appears at the peak of the normal power-law-like impulsive X-ray burst component, and it remains isothermal and dominates the X-ray emission below approx.30 keV through the decay of the flare event.

• Research Organization: Space Sciences Laboratory, University of California, Berkeley
• OSTI ID: 5729331
• Journal Information: Astrophys. J., Lett. Ed.; (United States), Journal Name: Astrophys. J., Lett. Ed.; (United States) Vol. 251:2; ISSN AJLEA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ELECTROMAGNETIC RADIATION
ELECTRONS
ELEMENTARY PARTICLES
ENERGY SPECTRA
FERMIONS
HARD X RADIATION
IONIZING RADIATIONS
LEPTONS
PLASMA
RADIATIONS
SOLAR ACTIVITY
SOLAR ELECTRONS
SOLAR FLARES
SOLAR PARTICLES
SOLAR RADIATION
SOLAR X-RAY BURSTS
SPECTRA
STELLAR RADIATION
X RADIATION
X-RAY SPECTRA