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Research Projects
Dr. Roman Makarevich
Personal Webpage
 A major interest of mine has been the research of the Earth's ionosphere. In particular, I am interested in the irregularity production mechanisms, energetic particle precipitation, and ionosphere-magnetosphere coupling. The understanding of the underlying physical mechanisms that govern behaviour of the plasma particles and waves in the solar-terrestrial environment is important not only from the fundamental plasma physics point of view but also can be used in practical applications, such as space weather monitoring and radio wave propagation. The ever-increasing variety of instruments, both in situ and ground-based, and amount of data available for rearchers have provided new and exciting opportunities for the research in Space Physics that simply did not exist just a few years ago.
Ionospheric Irregularities
 Coherent radars such as SuperDARN detect backscatter from magnetic-field-aligned irregularities or waves that act as tracers of the plasma flows in the ionosphere and magnetosphere. Studies of auroral irregularities involve data analysis from variety of sources such as coherent radars, plasma drift-meters, magnetometers, etc. In particular, I use information on the Doppler velocity at different radar frequencies (thus comparing irregularity phase velocities at different scales/wavelengths) in order to conclude on the irregularity production mechanisms.
Particle Precipitation
 Besides propagation conditions, the HF scatter is affected in a significant way by the radio wave absorption. The bulk of auroral absorption is due to energetic (>20 keV) electrons ionising the neutral gas at D/E-region heights. In the polar cap, solar flares produce greatly enhanced absorption causing blackouts in the radio communication. There is just one problem that needs to be investigated in the context of the space weather. During the substorms, the precipitating particles from the magnetotail cause similar, although less dramatic, effects in the upper atmosphere. My work is also focused on the investigation of various processes associated with the energetic particle precipitation in the high-latitude ionosphere. It involves data analysis from the imaging and widebeam riometers, magnetometers, and radars, as well as particle detectors and analysers. In order to distinguish between different precipitation mechanisms the principal approach is to combine the data from ground- and satellite-based instruments.
Convection Studies and Sub-Auroral Polarisation Streams (SAPS)
 The convection studies with ground-based instruments such as SuperDARN radars have several advantages such as global coverage and relatively good spatial and temporal resolution. The combined SuperDARN viewing area at present covers most of the auroral zone in both hemispheres. The TIGER radars operated by La Trobe University are capable of making observations in the subauroral region of the Earth's ionosphere. This capability is especially important since, despite the fact that there is a general view of the high-latitude convection patterns, the subauroral phenomena such as subauroral polarization streams (SAPS), the longitudinally extended channel-like subauroral regions of enhanced electric fields/plasma convection often developing after substorm onsets, and their role in the formation of the high-latitude convection patterns are significantly less investigated.
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