fl182.yoshimori07 Posted: 24-Jul-94 Updated: 18-Feb-95 Events specified: Flares of 27-Oct-91 05:39 UT and 15-Nov-91 22:37 UT
M.Yoshimori(Rikkyo University, E-mail: yosimori@rikkyo.ac.jp), K.Morimoto, K.Suga, T.Matsuda, Yu.D.Kotov (Moscow Engineering and Physics Institute), S.V.Bogovalov, O.V.Endrova and A.Yu.Suslov
Yohkoh observed Li and Be gamma-ray lines in the 1991 Oct.27 and Nov.15 flares. These two gamma-ray lines are produced by He-He reactions, and the line features provide diagnostics for angular distribution of interacting ions in the corona. Furthermore, we derive amounts of the Li and Be elements produced during solar flares from the gamma-ray line intensities. The derived ratio of the light element to hydrogen in the solar atmosphere is compared with that observed from optical observations. The present result is to be presented in the Rusian Conference on Cosmic Rays.
Required Observations: GRS and HXS spectral and time profile data.
Update 18-Feb-95
Yohkoh observed line features in the 400 - 500 keV region from two flares of 1991 October 27 and 1991 November 15. We have interpreted the line features in terms of a complex of Li-7 and Be-7 gamma-ray lines resulting from He-He reactions. We estimated the abundance of Li-7 produced by gamma-ray flares on basis of the observed two gamma-ray line fluences. It is one order of magnitude less than that derived from optical line observations.
Our paper entitled "Li-7 Production in Solar Flares" by Yu.D.Kotov, S.V.Bogovalov, O.V.Endalova and M.Yoshimori was accepted for publication in Space Science Review.