Irkutsk, Russian Federation
Pekin, China
Irkutsk, Russian Federation
, China
UDK 53 Физика
UDK 55 Геология. Геологические и геофизические науки
We study Alfvén waves generated in the magnetosphere during the passage of an interplanetary shock wave. After shock wave passage, the oscillations with typical Alfvén wave dispersion have been detected in spacecraft observations inside the magnetosphere. The most frequently observed oscillations are those with toroidal polarization; their spatial structure is described well by the field line resonance (FLR) theory. The oscillations with poloidal polarization are observed after shock wave passage as well. They cannot be generated by FLR and cannot result from instability of high-energy particle fluxes because no such fluxes were detected at that time. We discuss an alternative hypothesis suggesting that resonant Alfvén waves are excited by a secondary source: a highly localized pulse of fast magnetosonic waves, which is generated in the shock wave/plasmapause contact region. The spectrum of such a source contains oscillation harmonics capable of exciting both the toroidal and poloidal resonant Alfvén waves.
magnetosphere, plasmapause, shock front, Alfvén waves
1. Allan W., White S.P., Poulter E.M. Impulse-excited hydromagnetic cavity and field-line resonances in the magnetosphere. Planetary Space Sci. 1986, vol. 34, iss. 4, pp. 371–385. DOI: 10.1016/0032-0633(86)90144-3.
2. Chelpanov M.A., Mager O.V., Mager P.N., Klimushkin D.Y., Berngardt O.I. Properties of frequency distribution of Pc5-range pulsations observed with the Ekaterinburg decameter radar in the nightside ionosphere. J. Atmos. Solar-Terr. Phys. 2018, vol. 167, pp. 177–183. DOI: 10.1016/j.jastp.2017.12.002.
3. Cheremnykh O.K., Klimushkin D.Y., Mager P.N. On the structure of azimuthally small-scale ULF oscillations of a hot space plasma in a curved magnetic field: Modes with discrete spectra. Kinematics and Physics of Celestial Bodies. 2016, vol. 32, iss. 3, pp. 120–128. DOI: 10.3103/S0884591316030028.
4. Dai L., Takahashi K., Wygant J.R., Chen L., Bonnell J., Cattell C.A., Thaller S., Kletzing C., Smith C.W., MacDowall R.J., Baker D.N., Blake J.B., Fennell J., Claudepierre S., Funsten H.O., Reeves G.D., Spence H.E. Excitation of poloidal standing Alfvén waves through drift resonance wave-particle interaction. Geophys. Res. Lett. 2013, vol. 40, iss. 16, pp. 4127–4132. DOI: 10.1002/grl.50800.
5. Kim K.-H., Kim G.-J., Kwon H.-J., Distribution of equatorial Alfvén velocity in the magnetosphere: a statistical analysis of THEMIS observations. Earth, Planets and Space. 2018, vol. 70, iss. 1, 174. DOI: 10.1186/s40623-018-0947-9.
6. Kozlov D.A. Transformation and absorption of magnetosonic waves generated by solar wind in the magnetosphere. J. Atmos. Solar-Terr. Phys. 2010, vol. 72, iss. 18, pp. 1348–1353. DOI: 10.1016/j.jastp.2010.09.023.
7. Leonovich A.S. A theory of field line resonance in a dipole-like axisymmetric magnetosphere. J. Geophys. Res. 2001, vol. 106, iss. A11, pp. 25803–25812. DOI: 10.1029/2001JA000104.
8. Leonovich A.S., Mazur V.A. Resonance excitation of standing Alfvén waves in an axisymmetric magnetosphere (monochromatic oscillations). Planetary Space Sci. 1989, vol. 37, iss. 9, pp. 1095–1116. DOI: 10.1016/0032-0633(89)90081-0.
9. Leonovich A.S., Mazur V.A. Standing Alfvén waves with m≫1 in an axisymmetric magnetosphere excited by a non-stationary source. Ann. Geophys. 1998, vol. 16, iss. 8, pp. 914–920. DOI: 10.1007/s00585-998-0914-z.
10. Leonovich A.S., Mazur V.A. Structure of magnetosonic eigenoscillations of an axisymmetric magnetosphere. J. Geophys. Res. 2000, vol. 105, iss. A12, pp. 27707–27716. DOI: 10.1029/2000JA900108.
11. Liu W., Cao J.B., Li X., Sarris T.E., Zong Q.-G., Hartinger M., Takahashi K., Zhang H., Shi Q.Q. Angelopoulos V. Poloidal ULF wave observed in the plasmasphere boundary layer. J. Geophys. Res.: Space Phys. 2013, vol. 118, iss. 7, pp. 4298–4307. DOI: 10.1002/jgra.50427.
12. Moullard O., Masson A., Laakso H., Parrot M., Décreau P., Santolik O., Andre M. Density modulated whistler mode emissions observed near the plasmapause. Geophys. Res. Lett. 2002, vol. 29, iss. 20, 1975. DOI: 10.1029/2002GL015101.
13. Potapov A.S. ULF wave activity in high-speed streams of the solar wind: Impact on the magnetosphere. J. Geophys. Res.: Space Phys. 2013, vol. 118, iss. 10, pp. 6465–6477. DOI: 10.1002/2013JA019119.
14. Zong Q.-G., Leonovich A.S., Kozlov D.A. Resonant Alfvén waves excited by plasma tube/shock front interaction. Phys. Plasmas. 2018, vol. 25, iss. 12, 122904. DOI: 10.1063/1.5063508.
15. Zong Q., Rankin R., Zhou X. The interaction of ultra-low-frequency PC3–5 waves with charged particles in Earth’s magnetosphere. Rev. Modern Plasma Phys. 2017, vol. 1, iss. 1, 10. DOI: 10.1007/s41614-017-0011-4.
16. Zong Q.-G., Zhou X.Z., Wang Y.F., Li X., Song P., Baker D.N., Fritz T.A., Daly P.W., Dunlop M., Pedersen A. Energetic electron response to ULF waves induced by interplanetary shocks in the outer radiation belt. J. Geophys. Res. 2009, vol. 114, iss. A10, A10204. DOI: 10.1029/2009JA014393.
