ИСТИНА

Research in Astrophysics from Space(E). e2.5-0027.14. We have studied the powerful solar event of January 20, 2005 by nuclear-physics methods. We based on gamma-emission data of AVS-F apparatus from SONG-D detector onboard CORONAS-F satellite. By the statistical modeling method, proposed in MSU SINP, we calculated the temporal profile of 2.223-MeV line. The calculations were performed under assumptions of Bessel type of accelerated particles energy spectrum, different 3He content in the region of nuclear reactions to occur, and several density models of the solar atmosphere. The 4.44- and 6.13- MeV gamma-lines temporal profiles were also used. A comparison of the results of modeling with observational 2.223 MeV data reveals the numerical values of all mentioned parameters. The method gives the possibility to detect not only the time-averaged 2.223-MeV gamma-emission parameters over the whole flare, but also their evolution with the time of flare. Particularly, the comparison reveals an increase of the ratio of 3He/H concentrations during the flare from 2x10-5 at the rise phase of the gamma-ray flux up to 2x10-4 at the decay one. The 3He/H concentration ratio, averaged over whole time of 2.223-MeV gamma-emission, is equal to (1.40+-0.15)x10-4. The enlarged ratio of 3He/H in the region of nuclear reactions to occur and the increase of this ratio with the time may be understood by the supposition of the gradual accumulation of 3He in the photosphere and low chromosphere. In this case we can assume that the increased 3He content in the area of neutron interactions with the medium may be due to the predominant acceleration of 3He ions in the corona. Then the ions slow down and propagate in the solar atmosphere, downward to the lower chromosphere and photosphere, where they can be accumulated. Several authors proposed different mechanisms of 3He enrichment. For example, it was suggested that ion-acoustic turbulence could be responsible for this process (L. G. Kocharov et al., 1984), or ion-acoustic one in the crossing electrical and magnetic fields (V.P. Silin et al., 1988), or helical turbulence in non-potential, convolved magnetic fields (G. Fleyshman, et al., 2012). Thus, we make conclusion about the flows of 3He ions from the region of acceleration downwards to the low chromosphere and the photosphere. A number of observations confirms this supposition and gives more detailed substantiations and characteristics of the considered phenomena. We also take into consideration Coulomb energy loss of 3He ions energy. Some obtained numerical results are presented.