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Information × Registration Number 0203U008021, 0101U002778 , R & D reports Title Solar activity monitoring. Solar photosphere and chromosphere research popup.stage_title Head Akimov L., Registration Date 10-04-2003 Organization Kharkov National University named after V.N.Karazin popup.description2 The Sun is a subject of study. The goal of the work is as follows: taking fresh data on solar activity; study of flash activity of the Sun and its periodicity during 23 cycle of solar activity as compared to previous one; the investigation of the physical conditions and the structure of the low and middle chromosphere from D1,2 NaI lines; study of the day astroclimate on the site of the observational station of NSIA of the Kharkov National University. Monitoring of solar activity according to the program of ISSN and to special programs also has been performed. Date on 126 solar flares and 93 fast processes were obtained from 62 days of observations. Collected data were send to WDC and were published in SGD. Images of the Sun in different spectral lines were insert in Internet. Software was created to process the observations with CCD-matrix. The observations in Balmier continuum and HeI 1083 nm were carried out. To analyze the development of solar activity in 22th and 23th cycle both in optical and X-rays ranges the flare indices for these range (OFI, XFI) were calculated. Daily XFI indices for the period of 01.01.1986 to 31.05.2002 were represented on the site of NSIA of Kharkov Nation al University. It was found that XFI-indices reveal two maximum: in 2000 of July and 2002 of August. It was shown that the energy released by X-ray flares during the first 77 months of 22 cycle almost five times larger than that released by the flares in the present cycle for the same period. The power spectrum for XFI and OFI indices revealed statistically meaningful maximums for periods of 25.5, 36.5, 73, 116, 150 twenty-four hours that probably corresponded to the frequencies of Sun's flare activity. It was supposed that the changing electric charge of Mercury could influence the origin of flares. The calculations confirming the idea were made. To study the structure of the lower and middle chromosphere and to determine non-thermal motion in active and quiet regions of the chromosphere 350 spectra of the west limb of the Sun with D1,2 NaI lines obtained during the eclipse of July 31, 1981 were digitalized with a special automatic photometer. To obtain the charts of surface brightness in the D1,2 lines the software was modernized. The values of integral brightness for D1,2 NaI lines were obtain for all digitized spectra. The study will be continued. The observations of trembling of the solar limb were carried out with the help of a special device on the APhR-2-telescope to study the astroclimate on the observational station of NSIA of KhNU. It was found that the trembling amplitude during a stable weather had its minimum value (near 0.4'') at the morning and evening hours. Product Description popup.authors popup.nrat_date 2020-04-02 Close