Koval Alexandra Nikolaevna General data:
Born: 13.11.1935
Place of birth: Makeyevka village, Losyniv district, Chernihiv region, Ukrainian SSR
Studied in: T. G. Shevchenko Kyiv State University (since 1999 Taras Shevchenko Kyiv National University) (1952-1957);
Key interests: solar physics, polarimetry, polarimetry of Solar System bodies. PhD Thesis: Study of physical characteristics of mustaches and their connection with the development of active areas (1971 Main Astronomical Observatory of the USSR Academy of Sciences, Pulkovo);
Biography:
November 13, 1935 in the Makeyevka village of Losyniv district, Chernihiv region, Ukrainian SSR
During 1952-1957 she studied at the Faculty of Physics of the T. G. Shevchenko Kyiv State University. She graduated from the University with a degree in astronomy.
Since 1957 she has been an employee of the Crimean Astrophysical Observatory of the USSR Academy of Sciences. He is currently a senior researcher at the Department of Solar Physics.
In 1971 she defended her PhD thesis "Study of the physical characteristics of mustaches and their relationship with the development of active areas" (Decision of the Academic Council of the Main Astronomical Observatory of the USSR Academy of Sciences)
He studies the development of active regions on the Sun and non-stationary processes occurring in them, based on the analysis of monochromatic, spectral and polarization observations obtained on the main solar telescopes of the Crimean Astrophysical Observatory. She is author and co-author of 85 scientific publications.
The main areas of research of the scientist are the study of fine-grained non-stationary emission formations - mustaches. She was the first to determine the physical conditions in the mustache, the height of the radiating layer, explained the asymmetry of the emission of the mustache, studied the movements and structure of the magnetic field at the location of the mustache.
She studies the morphology, evolution, energy and spectral characteristics of powerful solar flares. Determines the correspondence of the observational characteristics of the flash process to the theoretical standard flash model.
She compared a number of spectral characteristics of proton and non-proton flashes, considered the possibility of detecting low-frequency plasma turbulence, studied the dynamic processes and structure of the velocity field in the flash volume of plasma and their compliance with the chromosphere evaporation model. She studied the role of thermal and non-thermal processes in the heating of the chromosphere on the basis of the study of the peculiarities of the linear polarization of Hα<\sub>-flash radiation. She found the fine structure of the polarized elements of the flash. She obtained and studied the spectra of white flash nuclei during the pulse phase, which showed a number of features previously unknown. Spectral features and model calculations of the structure of the atmosphere of white flashes indicate the heating of the lower chromosphere and photosphere, which is difficult to agree with the standard flash model.
Scientists have identified changes in the magnetic fields of spots during the flash, determined the intensity and structure of the magnetic field in the flash volume of the plasma. Rapid changes of the spot magnetic field during the pulsed phase of the flash and their correlation with non-thermal emission of the flash were revealed.
She identified the role of various parameters of the active area in creating a pre-flash situation in order to predict solar flares.
She is an active participant in observations from the International Solar Activity Research Program.
She was awarded the Veteran of Labor Medal for her selfless work.
Sources:
1 Астрономы России 1917-2017/ науч. ред. А.М.Черепащук, Казань, Казан. фед. ун-т, 2017.- 568с- C.222
2 Список дисертаційЮ захищених співпобітниками ГАО/Головна астрономічна обсерваторія Національної академії наук України: від ідеї створення до міжнародного визнання/За редакцією Я. С. Яцківа.-Київ: Наукова думка, 1918.-376 с.-С.327
