- Open Access
ULF pulsations observed by the ETS-VI satellite: Substorm associated azimuthal Pc 4 pulsations on the nightside
Earth, Planets and Space volume 50, pages63–80(1998)
The magnetic field data from the Engineering Test Satellite -VI (ETS-VI) have been analyzed to investigate the occurrence distributions of pulsations in Pc 3–5 frequency ranges in the magnetosphere. The observation of ETS-VI covered the invariant latitude (ILAT) range of 64.5°−69°ILAT near the geomagnetic equator (−10°−20° magnetic latitude) at all magnetic local time (MLT). Magnetic pulsations were selected by the Fast Fourier Transform method and checked by visual scanning if they have continuous waveforms. From the occurrence distributions of pulsations, we have found distinctive features in the following pulsations: (1) azimuthal Pc 5 pulsation; (2) azimuthal Pc 3 pulsation; (3) radial Pc 4 pulsation on the dayside; (4) azimuthal Pc 4 pulsations on the nightside. In respect of the first three types of pulsations (i.e., the azimuthal Pc 5 pulsation, the azimuthal Pc 3 pulsation, and the radial Pc 4 pulsation on the dayside), the results presented in this study confirm the previous results obtained by other satellite observations. The azimuthal Pc 4 pulsations on the nightside were observed in continuous waveforms lasting for about 10 minutes. Although the azimuthal Pc 4 pulsations on the nightside start at almost the same time as substorm onsets, they are different from Pi 2 pulsations in the magnetosphere. They are observed frequently in the MLT range of 23-04MLT with an occurrence peak at 01–02MLT. We suggest that the azimuthal Pc 4 pulsations on the nightside are excited through coupling to the fast mode Alfvén waves which were launched at substorm onset.
Anderson, B. J., M. J. Engebretson, S. P. Rounds, L. J. Zanetti, and T. A. Potemra, A statistical study of Pc 3–5 pulsations observed by the AMPTE/CCE magnetic fields experiment, 1. Occurrence distributions, J. Geophys. Res., 95, 10495–10523, 1990a.
Anderson, B. J., T. A. Potemra, L. J. Zanetti, and M. J. Engebretson, Statis-tical correlations between Pc 3–5 pulsations and solar wind/IMF parame-ters and geomagnetic indicies, Physics of Space Plasmas, SPI Conference Proceedings and Reprint Series, Number 10, pp. 419–429, Scientific Pub-lishers, Inc., Cambridge, MA, 1990b.
Arthur, C. W. and R. L. McPherron, Micropulsations in the morning sector, 3. Simultaneous ground-satellite observations of 10- to 45-s period waves near L = 6.6, J. Geophys. Res., 82, 2859–2866, 1977.
Arthur, C. W. and R. L. McPherron, The statistical character of Pc 4 magnetic pulsations at synchronous orbit, J. Geophys. Res., 86, 1325–1334, 1981.
Chapell, C. R., K. K. Harris, and G. W. Sharp, A study of the influence of magnetic activity on the location of the plasmapause as measured by OGO 5, J. Geophys. Res., 75, 50–56, 1970.
Chen, L. and A. Hasegawa, A theory of long-period magnetic pulsations, 1. Steady state excitation of field line resonance, J. Geophys. Res., 79, 1024–1037, 1974.
Cummings, W. D., R. J. O’Sullivan, and P. J. Coleman, Jr., Standing Alfvén waves in the magnetosphere, J. Geophys. Res., 74, 778–793, 1969.
Ellis, P. and D. J. Southwood, Reflection of Alfvén waves by non-uniform ionospheres, Planet. Space Sci., 31, 107–117, 1983.
Engebretson, M. J., L. J. Zanetti, T. A. Potemra, and M. H. Acuna, Harmon-ically structured ULF pulsations observed by the AMPTE CCE magnetic field experiment, Geophys. Res. Lett., 13, 905–908, 1986.
Hamlin, D. A., R. Karplus, R. C. Vik, and K. M. Watson, Mirror and az-imuthal drift frequencies for geomagnetically trapped particles, J. Geo-phys. Res., 66, 1–4, 1961.
Hughes, W. J., Magnetospheric ULF waves: A tutorial with a historical per-spective, in Solar Wind Sources of Magnetospheric Ultra-Low-Frequency Waves, Geophys. Monogr. Ser., vol. 81, edited by M. J. Engebretson, K. Takahashi, and M. Scholer, pp. 1–11, AGU, Washington, D. C., 1994.
Jacobs, J. A., Y. Kato, S. Matsushita, and V. A. Troitskaya, Classification of geomagnetic micropulsations, J. Geophys. Res., 69, 180–181, 1964.
Kokubun, S., Statistical characteristics of Pc 5 waves at geostationary orbit, J. Geomag. Geoelectr., 37, 759–779, 1985.
Kokubun, S., K. N. Erickson, T. A. Fritz, and R. L. McPherron, Local time asymmetry of Pc 4–5 pulsations and associated particle modulations at synchronous orbit, J. Geophys. Res., 94, 6607–6625, 1989.
Kuwashima, M., Wave characteristics of magnetic Pi 2 pulsations in the magnetosphere and on the ground, Mem. Kakioka Magn. Obs., 20, 1–15, 1983.
Lin, C. C. and L. J. Cahill, Jr., Pi 2 pulsations in the magnetosphere, Planet. Space Sci., 23, 693–711, 1975.
Nagai, T., T. Ondoh, H. Matsumoto, T. Goka, T. Fukuda, M. Nosé, T. Iye-mori, K. Takahashi, and S. Kokubun, ETS-VI magnetic field observations of the near-earth magnetotail during substorms, J. Geomag. Geoelectr., 48, 741–748, 1996.
Nosé, M., T. Iyemori, M. Sugiura, and J. A. Slavin, A strong dawn/dusk asymmetry in Pc 5 pulsation occurrence observed by the DE-1 satellite, Geophys. Res. Lett., 22, 2053–2056, 1995.
Olbert, S., Summary of experimental results from M.I.T. detector on IMP-1, in Physics of the Magnetosphere, edited by R. L. Carovillano, J. F. McClay, and H. R. Radoski, pp. 641–659, Reidel Doredrecht, 1968.
Potemra, T. A. and L. G. Blomberg, A survey of Pc 5 pulsations in the dayside high-latitude regions observed by Viking, J. Geophys. Res., 101, 24801–24813, 1996.
Saito, T., Long-period irregular magnetic pulsation, Pi 3, Space Sci. Rev., 21, 427–467, 1978.
Saito, T., K. Yumoto, and Y. Koyama, Magnetic pulsation Pi 2 as a sensitive indicator of magnetospheric substorm, Planet. Space Sci., 24, 1025–1029, 1976.
Saka, O., H. Akaki, O. Watanabe, and D. N. Baker, Ground-satellite correla-tion of low-latitude Pi 2 pulsations: A quasi-periodic field line oscillation in the magnetosphere, J. Geophys. Res., 101, 15433–15440, 1996a.
Saka, O., O. Watanabe, and D. N. Baker, A possible driving source for tran-sient field line oscillations in the postmidnight sector at geosynchronous altitudes, J. Geophys. Res., 101, 24719–24726, 1996b.
Sakurai, T. and R. L. McPherron, Satellite observations of Pi 2 activity at synchronous orbit, J. Geophys. Res., 88, 7015–7027, 1983.
Sakurai, T. and T. Saito, Magnetic pulsation Pi 2 and substorm onset, Planet. Space Sci., 24, 573–575, 1976.
Singer, H. J., W. J. Hughes, P. F. Fougere, and D. J. Knecht, The localization of Pi 2 pulsations: Ground-satellite observations, J. Geophys. Res., 88, 7029–7036, 1983.
Snyder, C. W., M. Neugebauer, and U. R. Rao, The solar wind velocity and its correlation with cosmic-ray variations and with solar and geomagnetic activity, J. Geophys. Res., 68, 6361–6370, 1963.
Southwood, D. J., Some features of field line resonances in the magneto-sphere, Planet. Space Sci., 22, 483–491, 1974.
Spiro, R. W., P. H. Reiff, and L. J. Maher, Jr., Precipitating electron energy flux and auroral zone conductances-An empirical model, J. Geophys. Res., 87, 8215–8227, 1982.
Takahashi, K. and B. J. Anderson, Distribution of ULF energy (f < 80 mHz) in the inner magnetosphere: A statistical analysis of AMPTE CCE magnetic field data, J. Geophys. Res., 97, 10751–10773, 1992.
Takahashi, K. and R. L. McPherron, Standing hydromagnetic oscillations in the magnetosphere, Planet. Space Sci., 32, 1343–1359, 1984.
Takahashi, K., S. Ohtani, and B. J. Anderson, Statistical analysis of Pi 2 pulsations observed by the AMPTE CCE spacecraft in the inner magne-tosphere, J. Geophys. Res., 100, 21929–21941, 1995.
Takahashi, K., B. J. Anderson, and S. Ohtani, Multisatellite study of night-side transient toroidal waves, J. Geophys. Res., 101, 24815–24825, 1996.
About this article
Cite this article
Nosé, M., Iyemori, T., Nakabe, S. et al. ULF pulsations observed by the ETS-VI satellite: Substorm associated azimuthal Pc 4 pulsations on the nightside. Earth Planet Sp 50, 63–80 (1998) doi:10.1186/BF03352087
- Occurrence Probability
- Fast Mode
- Magnetic Pulsation
- Magnetic Local Time
- Azimuthal Component