Nonthermal electrons in the thick-target reverse-current model for hard X-ray bremsstrahlung     

Yu. E. Litvinenko  B. V. Somov 《Solar physics》1991,131(2):319-336

The behaviour of the accelerated electrons escaping from a high-temperature source of primary energy in a solar flare is investigated. The direct current of fast electrons is supposed to be balanced by the reverse current of thermal electrons in the ambient colder plasma inside flare loops. The self-consistent kinetic problem is formulated; and the reverse-current electric field and the fast electron distribution function are found from its solution. The X-ray bremsstrahlung polarization is then calculated from the distribution function. The difference of results from those in the case of thermal runaway electrons (Diakonov and Somov, 1988) is discussed. The solutions with and without account of the affect of a reverse-current electric field are also compared.  相似文献   

Mechanism of thermonuclear burning propagation in a helium layer on a neutron star surface: A refined model with heat conduction and subgrid turbulence     

V. A. Simonenko  D. A. Gryaznykh  I. A. Litvinenko  V. A. Lykov  A. N. Shushlebin 《Astronomy Letters》2012,38(5):305-320

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A new model for the distribution of flare energies     

Yuri E. Litvinenko 《Solar physics》1996,167(1-2):321-331

A new model is presented for the distribution of solar (and stellar) flare energies. Flares are assumed to result from energy release in multiple reconnecting current sheets (RCSs) in the solar corona. The model takes into account both the dynamical evolution of separate RCSs and their interaction by virtue of coalescence. Thus an attempt is made to generalize previously suggested avalanche and RCS models for the flare frequency distribution. The number of RCSs is not specified and the strength of their interaction is governed by a coalescence parameter. Under quite general assumptions, the resulting distribution can be approximated by a power law with the slope 3/2 < < 7/4, as required by numerous observations. A softer distribution of numerous nanoflares, responsible for the coronal heating, is also possible under suitable choice of parameters.  相似文献   

Evidence for prolonged acceleration based on a detailed analysis of the long-duration solar gamma-ray flare of June 15, 1991   总被引：2，自引：0，他引：2  

V. V. Akimov  P. Ambrož  A. V. Belov  A. Berlicki  I. M. Chertok  M. Karlický  V. G. Kurt  N. G. Leikov  Yu. E. Litvinenko  A. Magun  A. Minko-Wasiluk  B. Rompolt  B. V. Somov 《Solar physics》1996,166(1):107-134

Gamma-ray emission extending to energies greater than 2 GeV and lasting at least for two hours as well as 0.8–8.1 MeV nuclear line emission lasting 40 min were observed with very sensitive telescopes aboard the GAMMA and CGRO satellites for the well-developed post-flare loop formation phase of the 3B/X12 flare on June 15, 1991. We undertook an analysis of optical, radio, cosmic-ray, and other data in order to identify the origin of the energetic particles producing these unusual gamma-ray emissions. The analysis yields evidence that the gamma-rays and other emissions, observed well after the impulsive phase of the flare, appear to be initiated by prolonged nonstationary particle acceleration directly during the late phase of the flare rather than by a long-term trapping of energetic electrons and protons accelerated at the onset of the flare. We argue that such an acceleration, including the acceleration of protons up to GeV energies, can be caused by a prolonged post-eruptive energy release following a coronal mass ejection (CME), when the magnetic field above the active region, strongly disturbed by the CME eruption, relaxes to its initial state through magnetic reconnection in the coronal vertical current sheet.  相似文献   

New data on the Precambrian age of Marunkeu eclogites (Polar Urals)     

V. L. Andreichev  Yu. L. Ronkin  P. A. Serov  O. P. Lepikhina  A. F. Litvinenko 《Doklady Earth Sciences》2007,413(3):347-350

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The geochemical transformation of natural soils and enhancement of agricenosis productivity due to volcanic ejecta entering the soil     

L. V. Zakharikhina  Yu. S. Litvinenko  N. I. Ryakhovskaya  V. V. Gainatulina  N. Yu. Arguneeva  M. A. Makarova 《Journal of Volcanology and Seismology》2016,10(3):203-217

It is found that the overwhelming majority of mobile forms of the chemical elements (up to 99%) that are thought to produce favorable effects when they arrive with volcanic ash to soils and supply additional elements that enhance the bioproductivity of ecosystems do not come in the form of ash particles, but in a gas-dissolved form directly from volcanic aerosol. Volcanic ash when considered independently of volcanic eruptions does not contain considerable amounts of accessible forms of chemical elements that would enable us to consider them as sources of nutrient elements for living organisms. However, the extensive range of elements that are contained in ash in ratios that are necessary for effective life activities invests these elements with catalytic properties that regulate the nutrient regime of plants and that can be used in agriculture in combination with lower amounts of traditional fertilizers to produce substantial (up to 72%) yield increases and to improve the quality of agricultural products.  相似文献   

On the Magnetic Field Orientation and Plasma Flows in Solar Filament Barbs     

Litvinenko  Yuri E. 《Solar physics》2000,196(2):369-375

Speeds of vertical flows in quiescent solar filaments are typically much less than the local Alfvén speed. This is why the flows in filament barbs can be modeled by perturbing a magnetostatic solution describing a balance between the Lorentz force, gravity, and gas pressure in a barb. This approach explains why some of the flows are neither aligned with the magnetic field nor controlled by gravity. Both the observed upflows and the magnetic field dips in barbs are likely to be caused by photospheric magnetic reconnection.  相似文献   

Stratigraphy of Upper Cretaceous-Paleogene deposits of northwestern Zeya-Burya sedimentary basin     

T.V. Kezina  N.D. Litvinenko 《世界地质(英文版)》2007,10(2)

In the northwestern Zeya-Bureya sedimentary basin, the authors studied coal deposits, including Ivanovsko-Erkovetskyu brown coal square on which is worked off largest Erkovetsky field of brown coal, extending to south flank of the Mesozoic-Cenozoic Belogor'e depression. The verified stratigraphic scheme of the coalfield sedimentary sequence is substantiated by palynological data on core samples from 18 boreholes sampled in the course of detailed prospecting and by paleobotanical analysis of sections in the Yuzhnyi sector of the coalfield. Sections of the Erkovtsy, Arkhara Boguchan, and Raichikha brown-coal mines are correlated. Stratigraphic subdivisions distinguished in the studied sedimentary succession are the middle and upper Tsagayan subformations (the latter incorporating the Kivda Beds), Raichikha and Mukhino formations.  相似文献   

Digital Economy as a Factor in the Technological Development of the Mineral Sector     

Litvinenko  V. S. 《Natural Resources Research》2020,29(3):1521-1541

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The Pressure Limitations on Flux Pile-up Reconnection     

Litvinenko  Yuri E. 《Solar physics》1999,186(1-2):291-300

The problem of the plasma pressure limitations on the rapidity of flux pile-up magnetic reconnection is re-examined, following the claim made by Jardine and Allen (1998) that the limitations can be removed by relaxing the assumption of zero-vorticity two-dimensional plasma flows. It is shown that for a two-dimensional stagnation point flow with nonzero vorticity the magnetic merging rate cannot exceed the Sweet–Parker scaling in a low-beta plasma. The pressure limitation appears to be much less restrictive for weak three-dimensional flux pile-up, provided the perturbation length scale in the third dimension is much less than the global length scale. The actual reconnection rate in the latter case, however, is much lower than this upper estimate unless the current sheet width is also much less than the global scale.  相似文献