აბასთუმნის ობსერვატორიის მკვლევარებმა გიორგი რამიშვილმა, ქეთევან ჯანაშიამ, თენგიზ მძინარიშვილმა, ბიძინა ჩარგეიშვილმა, ოლგა ავსაჯანიშვილმა, ელენა ფილიშვილმა და გულსუნ დუმბაძემ წარადგინეს პოსტერები The European Space Weather Week (ESWW12) -ის საერთაშორისო კონფერენციაზე, რომელიც 2015 წლის 23-27 ნოემბერს ჩატარდა ოსტენდეში (ბელგია). ESWW არის ევროპული ფორუმი კოსმოსური ამინდით დაინტერესებული მეცნიერებისთვის და მკვლევარებისთვის.
“Elaboration of a universal test on magneto sensitivity”
Ketevan Janashia, Alexander Tsibadze, Levan Tvildiani, Nikoloz Invia, Vasili Kukhianidze, George Ramishvili.
Abstract: The experiments revealed that during exposure of MF within the range of natural geomagnetic disturbances (5 nT – 200 nT) the autonomic nervous system balance in healthy male students is really shifted:
• In the case of initial balanced type of the autonomic nervous system regulation, the balance shift towards the sympathetic division was shown, indicating the intensification of sympathetic influence on the heart rhythm.
• In the case of initial parasympathetic type of the autonomic nervous system regulation, the shift towards the balanced regulation type was shown, indicating the intensification of sympathetic influence on the heart rhythm.
• In the case of initial balanced type regulation with elements of sympathetic divisions, the balance shift towards the balanced regulation was shown, indicating the intensification of parasympathetic influence on the heart rhythm.
• The impact of the natural geomagnetic storm in healthy individuals (group II) determines the intnsification of parasympathetic influence on the heart rhythm.
Based on the above, it can be supposed that the initial variations in the functional state of the investigated stipulates different dynamics of HRV alterations during the impact of both natural and modulated geomagnetic storms.
“Observational evidence of the reconnection and related oscillatory dynamics in active region AR 11429 on March 6, 2012”
E. Philishvili, B.M. Shergelashvili, V. Kukhianidze, G. Ramishvili, T.V. Zaqarashvili, M. Khodachenko,S. Poedts and P. De Causmaecker
Abstract: The complex solar magnetic fields in the corona represent cause and sources for different eruptive and explosive like events. We present the event, that was observed by SDO/AIA on 2012 March 6 in NOAA active region 11429. A M2.1 class flare (Fig.1) occurs at 12:23 UT, peaks at 12:41 UT and undergoes decay phase until 23:56 UT. From flare onset until 12:36 UT the variety of phenomena take place, including the reconnection, rapid plasma ejection and quasi-periodic oscillations, that might triggered solar flare. We investigated the spatial and temporal behavior of the magnetic loop structures with examining space-time diagrams and intensity change analysis along the coronal magnetic loops. We have obtained characteristic periods of oscillations of observed waves, that shows quasi-periodic behavior. We present two different interpretations for the observed dynamics. First, the oscillations with derived physical parameters provides evidence that these oscillations can be manifestation of longitudinal standing acoustic modes. Second, observed bright blobs could be signature of twisted coronal loop unstable to kink instability.
“On the long-period oscillations of the active region patterns: Method of least-square mapping on second order curves”
G. Dumbadze, B.M. Shergelashvili, V. Kukhianidze, G. Ramishvili, T.V. Zaqarashvili, M. Khodachenko, E. Gurgenashvili, S. Poedts and P. De Causmaecker
Abstract: Active Regions (ARs) are major sources of a variety of solar dynamic events. The development of automated detection and identification tools for solar features is required for a deeper understanding of the solar cycle. We studied the oscillatory dynamics of two ARs: NOAA 11327 and NOAA 11726, using two different methods of pattern recognition. In this work we developed a novel method of automated AR border detection and used another existing method for the proof-of-the-concept. The first method is using least square fitting on the smallest ellipse enclosing the AR and the second method applies regression on the convex hull. After processing the data we found that the axes and the inclination angle of both the ellipse and the convex hull oscillate in time. These oscillations are interpreted as the second harmonic of the standing long-period kink oscillations (with the node at the apex) of the magnetic flux tube connecting the two main sunspots of the ARs. We also found that the inclination angles oscillate with the characteristic periods 4.9 hours in AR 11726 and 4.6 hours in AR 11327, respectively. In addition, we discovered that the lengths of the pattern axes in the ARs oscillate with similar characteristic periods and these oscillations are ascribed to standing global flute modes. In both ARs we have estimated the distribution of the phase speed magnitude along the magnetic tubes (along the two main spots) by interpreting the obtained oscillation of the inclination angle as the standing second harmonic kink mode. After comparison of the obtained results for fast and slow kink modes, we concluded that both of these modes are good candidates to explain the observed oscillations of the AR inclination angles, as in the high plasma β regime the phase speeds of these modes are comparable and of the order of the Alfvén speed. Based on the properties of the observed oscillations, we detected the appropriate depth of the sunspot patterns, which are in good agreement with existing helioseismic estimations of this depth. The latter analysis can be used as a base for the development of a magneto-seismological tool for ARs.