MIEM HSE Scientists Come Closer to Unraveling the Mystery of Cloud Lightning Movement
At the general meeting of the Russian Academy of Sciences (RAS), held on April 23, research by Alexander Kostinskiy, Vladimir Rakov and Mikhail Andreev conducted in collaboration with their colleagues from academic institutes on the modeling and development of lightning was acknowledged as one of the most significant Russian scientific achievement in 2018.
At the Russian Academy of Science’s general meeting held on April 23, Academy President Alexander Sergeev presented a report of the major breakthroughs in Russian science. He particularly noted the findings of Alexander Kostinskiy, Deputy Director of HSE Tikhonov Moscow Institute of Electronics and Mathematics (MIEM HSE), Vladimir Rakov, Professor of the University of Florida and Leading Research Fellow of MIEM HSE, and Mikhail Andreev, Engineer of the Faculty of Physics, who, in collaboration with colleagues from the RAS Institute of Applied Physics, the VNIITF High-Voltage Center, and the Chinese Academy of Meteorology, conducted a series of studies on the development of lightning leaders. (The research is published in the following articles: Kostinskiy et al., 2018, JGR Atmospheres, v.123, 10* and Rakov et, al. 2018, IEEJ, v.138, 5**).
As the President of the Russian Academy of Sciences noted, lightning has long been an area of intense inquiry, but since it is extremely difficult to study in natural conditions, studies thus far have not been able to provide a detailed picture of the development of lightning leader steps. Studying a long spark with the aid of high-voltage generators, however, can give an idea.
It is known that, in nature, 90% of lightning is negative, that is, it is borne out of predominantly negatively charged parts of thunderclouds. High-speed cameras can show how hot negatively charged plasma channels, which are called negative leaders, move of clouds and move in abrupt steps to the ground. When a negative leader comes close to the ground, it initiates positive ascending leaders, which ascend towards it from high structures and trees. When a descending negative leader collides with an ascending positive leader, a single bright channel emerges between the cloud and the earth—this is what we know as a lightning bolt. From this collision, a wave of potential shoots upward and downward. The lightning channel heats up to 40 thousand degrees Celsius, rapidly expands and causes thunder.
But 10% of the discharges that reach the ground are positive, and they are more dangerous, since they cause a longer discharge with a higher energy input, and lightning rods are not able to provide very good protection against them. Most scientists believed that the positive lightning leaders move continuously or in very small steps, as opposed to the large steps of negative leaders.
When modeling lightning flashes on a high-voltage (6 MV) stand, researchers for the first time were able to obtain detailed images with high spatial resolution of the abrupt steps of positive leaders and negative leaders with nanosecond exposure. Consequently, a new hypothesis was formed about the formation of abrupt steps of positive leaders in a corona streamer burst, and X-ray fluxes from this area were measured.
These results allow scientists to interpret with much more accuracy the results of radio measurements of leading lightning channel plasma movements at high altitudes, which cannot be recorded with high-speed cameras, and thus better understand the nature of lightning propagation in storm clouds.
* Kostinskiy, A.Yu., V. S. Syssoev, N. A. Bogatov, E. A. Mareev, M. G. Andreev, M. U. Bulatov, D. I. Sukharevsky, and Rakov V. Abrupt Elongation (Stepping) of Negative and Positive Leaders Culminating in an Intense Corona Streamer Burst: Observations in Long Sparks and Implications for Lightning, Journal of Geophysical Research-Atmospheres, 2018, vol. 123. No. 10. P. 5360-5375, doi: 10.1029/2017JD027997
** Rakov, V. A., E. A. Mareev, M. D. Tran, Y. Zhu, N. A. Bogatov, A. Yu. Kostinskiy, V. S. Syssoev, W. Lyu. High-Speed Optical Imaging of Lightning and Sparks: Some Recent Results, IEEJ Transactions on Power and Energy. 2018, vol.138, no.5, pp.321-326, doi: 10.1541/ieejpes.138.321
Alexey Starobinsky, a professor of physics at HSE University and a fellow at the Landau Institute for Theoretical Physics at the Russian Academy of Science, has been awarded the Dirac Medal of the ICTP, a prestigious prize awarded annually by the Abdus Salam International Center for Theoretical Physics. HSE News Service spoke with the laureate about his path to international recognition, his students, and the award.
Students in the Faculty of Physics, one of the newest departments at HSE, will find a homey atmosphere, understanding teachers, and the opportunity to engage in science from the first year of studies. Physics students Arslan Galiullin (2nd year) and Sofia Lopatina (1st year) will be our guides for this instalment of the Open House project.
The HSE University competition committee has announced the winners of an international competition for new physics laboratory proposals. Two proposed projects were selected: the Laboratory of van der Waals Heterostructures, headed by Davit Ghazaryan, and the Laboratory of Nanophotonics and Functional Materials, headed by Andrey Krasavin.
Olesya Kondrakhina, ICEF Principles of Accounting lecturer, Assistant Lecturer for the Management Accounting programme at the University of London and three-time winner of the Best Teacher award at ICEF, spoke on how to keep a lecture hall full of students interested in accounting, the latest technical tools in her arsenal and a childhood dream.
A team of researchers from Germany and Russia have demonstrated that long contraction of muscles in one hand increases involuntary reaction of the other one. Meanwhile, the time between muscle contractions in both hands decreases. The results of the study have been published in the paper ‘Inverse relationshipbetween amplitude and latency of physiological mirror activity during repetitive isometric contractions’ in Neuroscience.
Anna Blyakhman has been appointed Director of HSE Nizhny Novgorod. She will be responsible for the overall administration of the campus.
The results of recent study conducted by the NASA Lunar Reconnaissance Orbiter, the agency’s automatic interplanetary station, show the existence of a ‘permafrost’ near the poles of the Moon with a relatively high content of water ice (up to 5% by weight). It is believed that water ice could supply a life support system for the future Russian Lunar Station and that it could also produce hydrogen-oxygen fuel for flights into deep space.
The new patented method is based on a superposition of functions and considerably enhances the speed and precision of Big Data processing. The project’s authors are Fuad Aleskerov, Tenured Professor at HSE and Head of the International Laboratory of Decision Choice and Analysis, Laboratory Researchers Sergey Shvydun, Evgeny Mitichkin and Vyacheslav Yakuba, as well as Vyacheslav Chistyakov, Professor at the HSE Campus in Nizhny Novgorod.
Researchers from HSE University and Yandex, as part of the LHCb collaboration at CERN, have been the first to discover CP violation in charm meson decays.