Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 33958 10.12737/stp-54201901 Results of current research Results of current research Results of current research Processes of energy release in low-power solar flares Processes of energy release in low-power solar flares https://orcid.org/0000-0001-5725-8262 Боровик Александр Васильевич Borovik Aleksandr Vasil'evich aborovik@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 https://orcid.org/0000-0002-9563-1360 Жданов Антон Андреевич Zhdanov Anton Andreevich kick.out@mail.ru Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation 5 4 3 9 https://zh-szf.ru/en/nauka/article/33958/view

Using flare patrol data for 1972–2010 [http://www.ngdc.noaa.gov/stp/space-weather/solar-data/solar-features/solar-flares/], we have conducted statistical studies of small solar flares. We have established a correlation between the flare brightness rise time and the total duration of small flares, and obtained evidence of the discreteness of relative rise times (Trel). The most significant Trel values are 0.2, 0.25, 0.33, and 0.5. As the area class and importance of flares increase, maxima of Trel distributions decrease, flatten, and completely disappear in case of large flares. We have found the discreteness of the area distribution of small flares. We have obtained distributions of solar flare energy, which exhibit significant overlap for flare energy of different area classes. The energy range of large solar flares contains 9.5 % of small flares. The energy range of flares of area class 1 has even a more significant overlap.

Using flare patrol data for 1972–2010 [http://www.ngdc.noaa.gov/stp/space-weather/solar-data/solar-features/solar-flares/], we have conducted statistical studies of small solar flares. We have established a correlation between the flare brightness rise time and the total duration of small flares, and obtained evidence of the discreteness of relative rise times (Trel). The most significant Trel values are 0.2, 0.25, 0.33, and 0.5. As the area class and importance of flares increase, maxima of Trel distributions decrease, flatten, and completely disappear in case of large flares. We have found the discreteness of the area distribution of small flares. We have obtained distributions of solar flare energy, which exhibit significant overlap for flare energy of different area classes. The energy range of large solar flares contains 9.5 % of small flares. The energy range of flares of area class 1 has even a more significant overlap.

 solar flares solar flares

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