A5019061262- Solar and Space Plasma Dynamics
- Ionosphere and magnetosphere dynamics
- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Physics of Superconductivity and Magnetism
- Magnetic and transport properties of perovskites and related materials
- Geomagnetism and Paleomagnetism Studies
- Iron-based superconductors research
- Radio Wave Propagation Studies
- Earthquake Detection and Analysis
- Inorganic Chemistry and Materials
- Gamma-ray bursts and supernovae
- Rare-earth and actinide compounds
- Solar Radiation and Photovoltaics
- X-ray Diffraction in Crystallography
- Photovoltaic System Optimization Techniques
- Geophysics and Gravity Measurements
- Crystal Structures and Properties
- Metallurgical Processes and Thermodynamics
- Nuclear materials and radiation effects
- Magnetic confinement fusion research
- Phase-change materials and chalcogenides
- Advanced Research in Science and Engineering
- Advanced Control and Stabilization in Aerospace Systems
- Luminescence Properties of Advanced Materials
National Academy of Sciences of Ukraine
1981-2024
Institute of Radio Astronomy
2013-2024
Frantsevich Institute for Problems in Materials Science
2024
KU Leuven
2014-2016
Lesya Ukrainka Volyn National University
2013
Austrian Academy of Sciences
2010
Space Research Institute
2010
Observatoire de Paris
2010
This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. Since 1998, performing on-the-fly dynamic spectrum calculations or waveform data recording without loss have been at the UTR-2 telescope, URAN VLBI system, GURT new generation telescope. Here, we detail these developed operation in strong interference environment that prevails range. Data collected with allowed us to discover numerous objects phenomena low frequencies, a summary of...
This paper deals with Type IIIb bursts, which were observed in the frequency band from 18 to 30 MHz. These bursts have fine structures contrary usual III bursts. The main properties of such as number striae a burst, their drift rates, durations, widths stria, emission fluxes are presented. It is also shown that parameters stria depend on position active areas solar disk.
Purpose: A historical review of the experimental baselopment low-frequency radio astronomy in Ukraine, its foundation half a century ago by an outstanding scientist S.Ya. Braude to current state. Design/methodology/approach: The constant progress electronic, computer and digital technologies, information telecommunication theory practice antenna receiving systems design, which introduction enriched hardware methodological ideology construction usage UTR-2, URAN, GURT telescopes, have been...
Rapid progress currently takes place in the field of low-frequency radio astronomy meterâdecameterâhectometer range wavelengths. It is caused by a radical modernization existing telescopes, creation new generation instruments, space-borne observations, and development research on all classes astrophysical objects, including Solar System. On other hand, difficulties specific to known, which are technical, methodological, physical limitations. An effective strategy for overcoming these...
An analysis of the observational polarization properties decameter spikes is presented in paper. It shown that possess high degree circular with average value about 60%. In frames “leading spot” theory we associated activity a certain active region on solar disk and determined mode emission. Supposing plasma emission mechanism link determine coronal fast electron beam parameters.
Spectral properties of a single type III burst in the wide frequency band from 10 to 70 MHz are studied detail. It is shown that electrons corresponding different levels emission move with velocities. Moreover, these electron velocities decrease maximum value, which corresponds 0.1 level flux at its front, minimum back. The velocity was approximately 0.31 c. This value equals 0.6 velocity, and, namely, it predicted by gas dynamic theory propagation through coronal plasma. In addition, we...
In the paper we present preliminary results of analysis solar Type IIIb bursts properties observed on June 14, 2012. Namely parameters their fine structure known as striae are studied in continuous frequency band 8 - 32 MHz. It is shown that durations and instantaneous bandwidths depend observing frequency. Notably, bandwidth increases duration decreases with The comparative decameter spikes also performed.
A decay of Type III burst into two bursts was registered during solar observations by GURT and URAN-2 radio telescopes on April 18, 2017. Such phenomenon observed for the first time. Newborn have drift rates smaller than that decaying burst. decays were predicted a gas-dynamic theory high-energy electron beams propagating through thermal background plasma. In frame this sources are beam-plasma structures moving with constant velocities. our case sum velocities newborn equals velocity source....
We discuss properties of a Type IV burst, which was observed on 2017 September 6, as result the powerful flare X 9.3. At decameter wavelengths this burst by radio telescopes STEREO A, URAN-2, and NDA at frequencies 5 - 35 MHz. This moving associated with coronal mass ejection (CME) propagating in southwest direction speed 1570 km/s. The maximum flux about 300 s.f.u. polarization more than 40%. In frequency range 8-33 MHz it continued for 2 hr. For A CME behind limb, its longitudinal angle...
Purpose: The overview of the scientifi c papers devoted to study solar decameter radio emission with world’s largest UTR-2 telescope (Ukraine) published for last 50 years. Design/methodology/approach: and analysis on both sporadic quiet (thermal) radiation Sun recorded at wavelength range. Findings: most signifi cant observational theoretical results studies obtained Institute Radio Astronomy National Academy Sciences Ukraine years are given. Conclusions: For fi rst time, frequencies below...
Cutting edge astrophysical studies require more and observing time at low-frequency radio telescopes, which is limited quite expensive. Modern digital signal processing systems still unable to provide affordable computational storage resources allow simultaneous beamforming in a wide frequency range for multiple studies. Low-frequency telescopes of new generation are very flexible could be split into subarrays or groups some do not large antenna effective area high directivity. In this paper...
Abstract We discuss properties of Type IV burst observed by radio telescopes URAN-2 (Ukrainian Radio Interferometer NASU-2) and NDA (Nançay Decameter Array) on 13 July 2022. This was registered at frequencies 26–80 MHz lasted from 07:00 to 12:00 UT. It had the fine structure in form sub-bursts similar decameter III-like bursts, with negative frequency drift rates − 5MHz/s -21MHZ/s sometimes positive drifts. Their durations were 1 s 2.6 most cases maximum fluxes up 700 s.f.u. At same time...
Studies of the quiet Sun radio emission were carried out in a wide range wavelengths from extremely short up to decameter ones. At longest wavelengths, measurements angular sizes solar corona previously using UTR-2 telescope scanning mode. We have developed simple interferometric technique for measuring diameter an extended source. It uses set interferometers formed antenna sections north-south and east-west arms measure size equatorial polar directions. The first observations with this...
We present results of observations Type IV burst with unusual high polarization equalled in maximum phase about 100%. This was registered both by URAN-2 and NDA radio telescopes on 13 July 2022. It continued for 5 hours consisted sub-bursts frequency drift rates had short durations. associate it the weak CME, which propagated East direction form thread-like structure. Theoretical description sub-burst plasma mechanism emission allow explaining their polarization,