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Information × Registration Number 0204U003173, 0101U002778 , R & D reports Title Solar activity monitoring. Solar photosphere and chromosphere research popup.stage_title Head Akimov L., Registration Date 16-02-2004 Organization Kharkov National University named after V.N.Karazin popup.description2 The subject of study is the Sun. The research purpose is:1. Getting a new solar activity data.2. Study of solar flare activity feature and its periodicity during 23 cycle of solar activity as compared to previous one.3. The investigation of the physical conditions and the structure of the upper photosphere, low and middle chromosphere by the solar spectrum taken during of solar eclipses.4. Study of the daily astroclimate on the site of the observational station of NSIA of the Kharkov National University.The solar activity monitoring was carried out on the international network of solar service program and on the special programs also. Date on 287 solar flares and 248 eruptive events were obtained from 156 days of observations. Collected data were send to World Data Centres and published in Solar Geophysical Data. Images of the Sun in different spectral lines were presented via Internet on the "KHASSM" website. "Space Weather" website was made, which is very popular on the Internet community. Software was created to process the observations with CCD-matrix. The observations in Balmer continuum and HeI 1083nm were carried out.The observation of Mercury transit on the solar disk was carried out successful. Obtained data will apply to centre to limb darkening function adjustment.Daily X-ray solar flare indices (XFI) were calculated for time interval from 1.01.81 to 31.05.03. The solar activity evolution was analysed by optical and X-ray flare indices at 21-23 solar cycles. The last cycle peculiarity was found out in comparison with previous ones.The statistically significant maximums of XFI and OFI indices power spectrum was found for differential rotation periods (26.5, 27,28.2 days) and for periods of ~25.5, 33, 36.5, 73, 116, 150 and 225 days that probably corresponded to the frequencies of solar flare activity. The difference between 22 and 23 solar cycles was found at the spectral power of these periods. It was supposed that the changing electric charge of Mercury could affect the origin of flares. The calculations confirming the idea were made.The map of chromosphere surface intensity distribution was investigated at D3 HeI line by two solar eclipses observation. It permits to detect some differences on helium chromosphere structure for different parts of solar activity cycle. It was coronal X-radiation with wavelength <6 nm can reach minimal temperature layer. The offered conception explains observed data of helium radiation from minimal temperature layer.For the first time the intensity distribution maps of photosphere near the solar limb and lower chromosphere in D1,2 NaI lines were made by solar eclipse spectrum at 31.7.1981y. The heterogeneous structure of photosphere and chromosphere radiation was found. The heterogeneity dimensions correspond to meso- and super granulation. The observation quiet photospheric intensity distribution was similar to HSRA model.For the first time the map of D2/D1 ratio of sodium resonance doublet on height distribution was made. It was found the chromosphere height on active regions lower then quiet ones.Day astroclimate investigation was made on NIIA KhNU station. It was found that the mean-square trembling amplitude is < 1" in 70% cases. And it is < 0.9" in summer during steady anticyclones. In the morning and in the evening it amount 0.5" - 0.6". The conclusion about expediency to utility new telescope with high spatial resolution on AI KhNU was made. Product Description popup.authors popup.nrat_date 2020-04-02 Close