ON A NEW CLASS OF IMPULSIVE FLARES WITH NO NUCLEAR GAMMA-RAY LINE EMISSION

The new class of γ-ray spectra from impulsive flares without nuclear γ-ray lines is compared with bremsstrahlung spectra of energetic electrons undergoing stochastic acceleration, Coulomb and synchrotron losses. The remarkable agreement of both the produced γ-spectra from the precipitated electrons and the electron spectra measured in the interplanetary space leads to the conclusion that seed population and acceleration process are identical for both classes of electrons. A new estimate of the electron bremsstrahlung contribution in γ-spectra of impulsive solar flares seems to be necessary. © 1990 Kluwer Academic Publishers.