ИСТИНА

The method of solar flares study, using neutron secondary reactions, supposes the knowledge or suppositions about vertical profile density of surrounding medium, chemical and isotopic composition of the acceleration region and deeper layers of the solar atmosphere. Our studies are founded on nuclear methods by study some characteristics of primary and secondary gamma-emissions from nuclear reactions between accelerated particles and surrounding matter. Initially we have used the standard density models. Later we also composed new models to find the best ones for describe the processes in the flares. We present a short survey of the solar atmosphere density vertical profile models and using them in the solar flares researches.