Труды сотрудников ИВМ СО РАН

/ C. J. Farrugia [et al.] // J. Atmos. Sol.-Terr. Phys. - 2013. - Vol. 99. - P14-26, DOI 10.1016/j.jastp.2012.11.014. - Cited References: 53. - C.J.F. is supported by NASA Grant NNX10AQ29G and NSF Grant AGS-1140211. N.V.E. acknowledges support from Austrian Science Fund Project I193-N16 and RFBR Grant no 12-05-00152-a. N.L. acknowledges support from NSF Grant AGS-1140211. Work at LANL was conducted under the auspices of the U.S. Department of Energy with partial support from NASA and NSF. . - 13. - ISSN 1364-6826РУБ Geochemistry & Geophysics + Meteorology & Atmospheric Sciences

Аннотация: The interaction of interplanetary coronal mass ejections (ICMEs) and magnetic clouds (MCs) with the Earth's magnetosphere exhibits various interesting features principally due to interplanetary parameters which change slowly and reach extreme values of long duration. These, in turn, allow us to explore the geomagnetic response to continued and extreme driving of the magnetosphere. In this paper we shall discuss elements of the following: (i) anomalous features of the flow in the terrestrial magnetosheath during ICME/MC passage and (ii) large geomagnetic disturbances when total or partial mergers of ICMEs/MCs pass Earth. In (i) we emphasize two roles played by the upstream Alfven Mach number in solar wind-magnetosphere interactions: (i) It gives rise to wide plasma depletion layers. (ii) It enhances the magnetosheath flow speed on draped magnetic field lines. (By plasma depletion layer we mean a magnetosheath region adjacent to the magnetopause where magnetic forces dominate over hydrodynamic forces.) In (ii) we stress that the ICME mergers elicit geoeffects over and above those of the individual members. In addition, features of the non-linear behavior of the magnetosphere manifest themselves. (C) 2012 Elsevier Ltd. All rights reserved.


Доп.точки доступа:
Farrugia, C.J.; Erkaev, N.V.; Еркаев, Николай Васильевич; Jordanova, V.K.; Lugaz, N.; Sandholt, P.E.; Muhlbachler, S.; Torbert, R.B.

/ N. V. Erkaev [et al.] // Geophys. Res. Lett. - 2012. - Vol. 39. - Ст. L01103, DOI 10.1029/2011GL050209. - Cited References: 16. - This work was done while NVE was on a research visit to the Space Science Center of UNH. This work is supported by RFBR grant N 09-05-91000-ANF_a, and also by the Austrian "Fonds zur Forderung der wissenschaftlichen Forschung" under Project I 193-N16 and the "Verwaltungsstelle fur Auslandsbeziehungen" of the Austrian Academy of Sciences. Work by CJF was supported by NASA grants NNX10AQ29G and NNX08AD11G. . - ISSN 0094-8276РУБ Geosciences, Multidisciplinary

Аннотация: In previous work we used a semi-analytical treatment to describe accelerated magnetosheath flows caused by the draping of interplanetary magnetic field (IMF) lines around the magnetosphere. Here, we use the same approach, i.e., modeling the magnetic field lines as elastic strings, to examine how the magnetic tension force, one of the two agents responsible for producing these flows, varies along field lines away from the equatorial plane. The bend in the field line caused by the draping mechanism propagates as two oppositely-directed waves to higher latitudes. For a due northward IMF - the case we consider here - these propagate symmetrically north/south of the equatorial plane. As a result, a two-peaked latitude velocity profile develops as we go further downtail and the velocity peaks migrate along the magnetic field line to higher latitudes. We examine this velocity-profile for two Alfven Mach numbers (M-A = 8 and 3), representative of conditions in the solar wind at 1 AU ("normal" solar wind and solar transients). Qualitatively, the picture is the same but quantitatively there are important differences: (i) the flows reach higher values for the lower M-A (maximum V/V-SW = 1.6) than for the higher M-A (V/V-SW = 1.3); (ii) asymptotic values are reached farther downstream of the dawn-dusk terminator for the lower M-A (similar to-50 R-E vs -15 R-E); (iii) For the lower M-A the highest speeds are reached away from the equatorial plane. We predict two channels of fast magnetosheath flow next to the magnetopause at off-equatorial latitudes that exceed the solar wind speed. Citation: Erkaev, N. V., C. J. Farrugia, A. V. Mezentsev, R. B. Torbert, and H. K. Biernat (2012), Accelerated magnetosheath flows caused by IMF draping: Dependence on latitude, Geophys. Res. Lett., 39, L01103, doi:10.1029/2011GL050209.

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Доп.точки доступа:
Erkaev, N.V.; Еркаев, Николай Васильевич; Farrugia, C.J.; Mezentsev, A.V.; Torbert, R.B.; Biernat, H.K.

[Text] / C. J. FARRUGIA [et al.] ; ed. H. K. BIERNAT // MAGNETOSHEATH. Ser. ADVANCES IN SPACE RESEARCH : PERGAMON PRESS LTD, 1994. - Vol. 14: Topical Meeting of the COSPAR Interdisciplinary Scientific Commission D of the COSPAR 29th Plenary Meeting (AUG 28-SEP 05, 1992, WASHINGTON, DC), Is. 7. - P105-110, DOI 10.1016/0273-1177(94)90055-8. - Cited References: 15 . - ISBN 0273-1177. - ISBN 0-08-042484-8РУБ Engineering, Aerospace + Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: We present magnetic field and particle (protons and electrons) observations in the sheath region behind an interplanetary shock driven by a magnetic cloud, and in the magnetic cloud itself. We also discuss observations in the dayside terrestrial magnetosheath during cloud passage. We find that the region ahead of the cloud is in pressure balance. Further, throughout its extent ( 0.06 AU), the magnetic field strength is anticorrelated with the plasma density, with the latter decreasing steadily as the cloud is approached. This behaviour is indicative of magnetic forces influencing the Row topology and highlights a large-scale breakdown of predictions based solely on gas dynamical considerations. We also study density stuctures inside the cloud which result in an undulating dynamic pressure being applied to the magnetopause causing it to oscillate with amplitudes of similar to 1 similar to 3 Re and period similar to 2h.


Доп.точки доступа:
FARRUGIA, C.J.; FITZENREITER, R.J.; BURLAGA, L.F.; Erkaev, N.V.; Еркаев, Николай Васильевич; OSHEROVICH, V.A.; BIERNAT, H.K.; FAZAKERLEY, A.; BIERNAT, H.K. \ed.\