Irkutsk, Russian Federation
Irkutsk, Russian Federation
Irkutsk, Russian Federation
We have studied Ca II K line profiles, using two time series of spectrograms taken in two regions near the solar disk center. In each of the regions, the spectrograph slit cut out several areas of the quiet region and a plage. For the selected chromospheric structures, we have derived K line profiles and have defined a number of parameters that characterize the spatial and temporal variations of the profiles. The analysis of profile shapes in different structures belonging to the same moment of time has shown that there are structures whose profiles differ only slightly from each other in the photosphere, but differ dramatically in the chromosphere. The structures begin to differ from the level of formation of K1 and continue to differ further in the chromosphere. There are, however, structures which begin to differ at the level of the photosphere and continue to differ in the chromosphere. The difference between profile shapes in different structures is likely to be associated both with different thermodynamic conditions and with different magnetic field topology at a given point at a given time. We have examined temporal variations of the K Ca II line profiles in structural chromospheric elements, which are caused by the process of K2v-grains. In most of the studied areas of the chromospheric structures, the brightening of the K2v peak develops according to the “common” scenario: at the time of maximum bright-ness, the line shifts toward the red side. There are, however, cases when the brightening of the K2v peak occurs with a shift of the line to the violet side or with no shift at all. We have constructed scatter plots for some pairs of profile parameters related to intensities at characteristic points of the profile and their shifts. A correlation has been found between intensities in the center and wings of the K line. The correlation between shifts of the K2v and K2r peaks is very weak or completely absent.
chromosphere, K Ca II profiles, K2v grains
ВВЕДЕНИЕ
Благодаря развитию наблюдательной техники и теоретических методов накоплен большой объем знаний о хромосфере Солнца, однако ряд вопросов, связанных с физическими процессами, происходя-щими в этом слое, нуждается в дальнейшем уточнении. В этом контексте представляют интерес результаты, которые могут подтвердить уже полученные ранее и добавить уверенности в достоверности последних.
Данная работа является продолжением предыдущей работы авторов [Grigoryeva et al., 2016] по исследованию линий Ca II, основанной на наблюдениях двух областей, расположенных в основании корональной дыры. Каждая область включает уча-сток спокойной хромосферы с яркими и темными структурами и флоккул.
Цель работы — исследовать некоторые особенности пространственных и временных вариаций контуров линии K Ca II в различных хромосферных структурах.
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Работа выполнена в рамках базового финансирования программы ФНИ II.16. Результаты получены с использованием оборудования Центра коллективного пользования «Ангара», http://ckp-rf.ru/ckp/3056.
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