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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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The solar plasma is accelerated near the Sun and creates the solar wind (SW), which is collisionless with respect to Coulomb collisions. To simulate SW properties, it is necessary to identify a set of boundary conditions, especially on the magnetic field. On the other hand, the Sun moves through the local interstellar medium (LISM), which is affected by the presence of the heliosphere. The SW--LISM interaction creates the heliospheric termination shock (TS) and the heliopause (HP), both observed in situ by Voyager 1 (V1) and Voyager 2 (V2) spacecraft. The LISM plasma is collisional, but only partially ionized. Charge exchange between ions and atoms plays a major role in the SW--LISM interaction. As new populations of neutral atoms are born in the SW and LISM, some of them can propagate far upstream into the LISM and modify it to such extent that the mere existence of a bow shock cannot be confirmed knowing the properties of the unperturbed LISM only. In addition, nonthermal (pickup) ions (PUIs) are created. They generate turbulence which heats up the thermal ions. PUIs are further accelerated to create anomalous cosmic rays (ACRs). The heliosphere beyond the ionization cavity is dominated thermally by PUIs. According to Decker et al. (2015, 2018), the inner heliosheath (IHS) pressure contributed by energetic PUIs and ACRs far exceeds that of the thermal background plasma and magnetic field. PUIs are of importance also in the outer heliosheath (OHS) -- the LISM region affected by the presence of the heliosphere. Both the charge exchange and PUI transport phenomena require kinetic treatments. PUIs are measured in situ by Ulysses and New Horizons (NH) spacecraft. Charge exchange of PUIs with neutral atoms creates the secondary, energetic neutral atoms (ENAs), which can propagate to near-Earth distances from their birth locations beyond the TS. The fluxes of ENAs were measured in the past by SOHO and Cassini, and have been measured by the Interstellar Boundary Explorer (IBEX) since 2009. The energy bands covered are from 10 eV to 88 keV. Since the ENA properties bear imprints of the parent PUIs, it is possible to deconvolve 3-D properties of the heliosphere and LISM from the ENA measurements. The Interstellar Mapping and Acceleration Probe (IMAP) mission, to be launched by NASA in 2024, will make such measurements even more accurately. Our SW--LISM model has been successful in interpreting and/or predicting a number of non-trivial observations: (1) the effect of ISMF on the neutral hydrogen deflection plane; (2) strong correlation of the IBEX ribbon position on full-sky maps and the orientation of the BV-plane defined by the LISM velocity and ISMF vectors, in the unperturbed LISM; (3) the modeled H density at the TS is in agreement with that derived from PUI measurements; (4) the effect of PUIs on the TS, (5) the TS and HP positions at V1 and V2, (5) backward SW velocities at V1, (6) time-dependent MAG and PWS observations at V1 on the LISM side of the HP, and (6) the observed anisotropy in the 1--10 TeV galactic cosmic ray flux. The latter observation has been reproduced on the basis of our SW--LISM interaction model, which requires the heliotail to have a comet-like shape. We discuss new results related to the effect of the HP instability on the GCR transport and shock interaction patterns in the LISM, as well as their effect on turbulence observations. A comparative analysis of different SW-LISM interaction models is given.