Ground-based observations of an onset of localized field-aligned currents during auroral breakup around magnetic midnight
Article Sidebar
Published:
Mar 27, 1980
Keywords:
Auroral substorm,
Magnetic substorm,
Substorm onset,
Field-aligned currents,
Auroral electrojet
Volumes
Vols. 1-18 (1924-1944), ISSN 0044-2801
Main Article Content
Abstract
The substorm on 2 March 1978 was selected for study as a relatively weak substorm, starting at about local magnetic midnight, that could be observed with instruments in Northern Scandinavia. The analysis is based on a comparative study of data from the IMS magnetometer network, all-sky cameras, pulsation magnetometers, and riometers in the Scandinavian area. In addition other data are used to support the results, e.g., a photograph from the DMSP-F2 satellite, showing the auroral situation over Scandinavia, and further west, immediately after the substorm onset. The substorm was preceded by a weak activation of aurora and magnetic disturbance about 3 min before the onset. After a fading that lasted for 20 s and could be observed only in optical aurora, the substorm onset led to a strong brightening of the aurora, an enhancement of the westward electrojet, a sudden rise in the ionospheric D-layer absorption, and Pi B type pulsations. Immediately after the onset, the ground magnetic data suggest the appearence of a pair of oppositely directed, localized, field-aligned currents (FACs). The main development of the signatures of the downward FAC was clearly delayed by about 3 min. There were significant correlations between the magnetic signatures of the two FACs and different features and spectra of the optical aurora, both in time and location. The observed Pi B type pulsations lasted as long as a growth in the local onset-connected FACs could be inferred. Within the first three minutes the localized three dimensional current system developed into a more sheet-like configuration. An expansion to the west, possibly accompanied by a westward travelling surge, was traced with riometers and magnetometers on Iceland and Greenland.
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How to Cite
Opgenoorth, H., Pellinen, R., Maurer, H., Kuppers, F., Heikkila, W., Kaila, K., & Tanskanen, P. (1980). Ground-based observations of an onset of localized field-aligned currents during auroral breakup around magnetic midnight. Journal of Geophysics, 48(1), 101-115. Retrieved from https://journal.geophysicsjournal.com/JofG/article/view/208
Section
References
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Akasofu, S.-I. (1974) A study of auroral displays photographed from the DMSP-2 satellite and from the Alaska meridian chain of stations. Space Sci. Rev. 16:617-725
Akasofu, S.-I. (1977) Physics of magnetospheric substorms. Dorndrecht, Boston: Reidel Publ. Comp.
Akasofu, S.-I., Eather, R.H., Bradbury, J.N. (1969) The absence of the Hydrogen emission H|beta in the westward traveling surge. Planet. Space Sci. 17:1409-1412
Akasofu, S.-I., Kimball, D.S., Meng, Ch.-I. (1965a) The dynamics of the aurora II: westward traveling surges. J. Atmos. Terr. Phys. 27:173-187
Akasofu, S.-I., Kimball, D.S., Meng, Ch.-I. (1965b) The dynamics of the aurora V: Poleward motions. J. Atmos. Terr. Phys. 27:497-503
Atkinson, G. (1971) Magnetosphere flows and substorms, In: Proceedings of Advanced Study Inst. on Magnetosphere Ionosphere Interactions, Dalseter, Norway
Bannister, J.R., Gough, D.I. (1977) Development of a polar magnetic substorm: A two-dimensional magnetometer array study. Geophys. J. R. Astron. Soc. 51:75-90
Bannister, J.R., Gough, D.I. (1978) A study of two polar magnetic substorms with a two-dimensional magnetometer array. Geophys. J. R. Astron. Soc. 53:1-26
Baumjohann, W. (1979) Spatially inhamogeneous current configurations as seen by the Scandinavian magnetometer array. In: Proceedings of the International Workshop on Selected Topics of Magnetospheric Physics. Tokyo, March
Baumjohann, W., Greenwald, R.A., Kuppers, F. (1978) Joint magnetometer array and radar backscatter observations of auroral currents in northern Scandinavia. J. Geophys. 44:373-383
Bostrom, R. (1964) A Model of the auroral electrojets. J. Geophys. Res. 69:4983-4999
Bostrom, R. (1977) Current systems in the magnetosphere and ionosphere. In: Brekke, A. (Ed.) Radar probing of the auroral plasma, Proc. EISCAT Summer School, Tromso, Norway, June 5-13 1975, Universitatsfortlaget, Tromso-Oslo-Bergen
Boyd, J.S., Belon, A.E., Romick, G.J. (1971) Latitude and time variations in precipitated electron energy inferred from measurements of auroral heights. J. Geophys. Res. 76:7694-7700
Brekke, A., Doupnik, J.R., Banks, P.M. (1974) Incoherent scatter measurements of E region conductivities and currents in the auroral zone. J. Geophys. Res. 79:3773-3789
Clauer, C.R., McPherron, R.L. (1974) Mapping the local time - universal time development of magnetospheric substorms using midlatitude observations. J. Geophys. Res. 79:2811-2820
Eather, R.H. (1979) DMSP calibration. J. Geophys. Res. 84:4134-4144
Fukunishi, H. (1975) Dynamic relationship between proton and electron auroral substorms. J. Geophys. Res. 80:553-574
Fukushima, N. (1974) Equivalent current pattern for a field-aligned current into the auroral belt of enhanced electric conductivity, Part I: Case of no charge accumulation at the auroral-zone boundaries. Rep. Ionos. Space Res. Jpn. 28:207-213
Fukushima, N. (1975a) Equivalent current pattern for a field-aligned current into the auroral belt of enhanced electric conductivity, Part II: Case of charge accumulation at the auroral-zone boundaries. Rep. Ionos. Space Res. Jpn. 29:31-38
Fukushima, N. (1975b) Equivalent current pattern for a field-aligned current into the auroral belt of enhanced electric conductivity, Part III: Case of open field lines on the poleward side and closed field lines on the equatorward side of the auroral belt. Rep. Ionos. Space Res. Jpn. 29:39-46
Fukushima, N. (1976) Generalized theorem for no ground magnetic effect of vertical currents connected with Pedersen currents in the uniform-conductivity ionosphere. Rep. Ionos. Space Res. Jpn. 30:35-40
Greenwald, R.A., Weiss, W., Nielsen, E., Thomson, N.R. (1978) Stare, a new radar auroral backscatter experiment in northern Scandinavia. Radio Sci. 13 (In press)
Gustafsson, G. (1970) A revised corrected geomagnetic coordinate system. Ark. Geotys. 5:595-617
Harang, L. (1946) The mean field of disturbance of polar geomagnetic storms. Terr. Magn. Atmos. Electr. 51:353-380
Heikkila, W.J., Pellinen, R.J. (1977) Localized induced electric field within the magnetotail. J. Geophys. Res. 82:1610-1614
Heppner, J.P. (1954) Time sequences and spatial relations in auroral activity during magnetic bays at College, Alaska. J. Geophys. Res. 59:329-338
Hypponen, M., Pellinen, R.J., Sucksdorff, C., Torniainen, R. (1974) Digital all-sky camera. Technical report No. 9, Finnish Metereol. Inst.
Iijima, T., Potemra, T.A. (1976) The amplitude distribution of fieldaligned currents at northern high latitudes observed by Triad. J. Geophys. Res. 81:2165-2174
Kamide, Y., Akasofu, S.-I. (1975) The auroral electrojet and global auroral features. J. Geophys. Res. 80:3585-3602
Kamide, Y., Rostoker, G. (1977) The spatial relationship of fieldaligned currents and auroral electrojets to the distribution of nightside auroras. J. Geophys. Res. 76:5589-5608
Kamide, Y., Akasofu, S.-I., Deforest, S.E., Kisabeth, J.L. (1975) Weak and intense substorms. Planet. Space Sci. 23:579-587
Kisabeth, J.L. (1972) The dynamical development of the polar electrojets. Edmonton: PhD Thesis, University of Alberta
Kisabeth, J.L., Rostoker, G. (1971) Development of the polar electrojet during polar magnetic substorms. J. Geophys. Res. 76:6815-6828
Kisabeth, J.L., Rostoker, G. (1973) Current flow in auroral loops and surges inferred from ground-based magnetic observations. J. Geophys. Res. 78:5573-5584
Kisabeth, J.L., Rostoker, G. (1974) The expansive phase of magnetospheric substorms. I. Development of the auroral electrojets and auroral arc configuration during a substorm. J. Geophys. Res. 79:972-984
Kisabeth, J.L., Rostoker, G. (1977) Modelling of the three-dimensional current systems associated with magnetospheric substorms. Geophys. J.R. Astrom. Soc. 49:655-683
Klumpar, D.M. (1979) Relationship between auroral particle distributions and magnetic field perturbations associated with fieldaligned currents (accepted for publication). J. Geophys. Res.
Klumpar, D.M., Burrows. J.R., Wilson, M.D. (1976) Simultaneous observations of field-aligned currents and particle fluxes in the post-midnight sector. Geophys. Res. Lett. 3:395-398
Kuppers, F., Untiedt, J., Baumjohann, W., Lange, K., Jones, A.G. (1979) A two-dimensional magnetometer array for groundbased observations of auroral zone electric currents during the International Magnetospheric Study (IMS). J. Geophys. 46:429-450
Lui, A.T.Y., Venkatesan, D., Anger, C.D., Akasofu, S.-I., Heikkila, W.J., Winningham, J.D., Burrows, J.R. (1977) Simultaneous Observations of particle precipitations and auroral emissions by the ISIS 2 satellite in the 19-24 MLT sector. J. Geophys. Res. 82:2210-2226
Maurer, H., Theile, B. (1978) Parameters of the auroral electrojet from magnetic variations along a meridian. J. Geophys. 44:415-426
McPherron, R.L. (1970) Growth phase of magnetospheric substorms. J. Geophys. Res. 75:5592-5599
McPherron, R.L. (1979) Magnetospheric substorms. Rev. Geophys. Space Phys. 17:657-681
McPherron, R.L., Russel, C.T., Aubry, M.P. (1973) Satellite studies of magnetospheric substorms on August 15, 1968. 9. Phenomenological model for substorms. J. Geophys. Res. 79:3131-3149
Mozer, F.S. (1971) Origin and effects of electric fields during isolated magnetospheric substorms. J. Geophys. Res. 76:7595-7608
Oguti, T., Fukunishi, H., Tohmatsu, T., Nagata, T (1974) H|beta -emissions during auroral breakup. Memoirs of National Inst. of Polar Research, Special Issue No. 3, Proceedings of antarctic review
meeting, 10-20
Opgenoorth, H.J. (1978) Vergleich von Strukturen im Polarlicht und im Magnetfeld gleichzeitiger lonospharenstrome. Diplomarbeit Physik, Inst. f. Geophys. Univ. Munster, FRG
Pellinen, R.J. (1979) Induction model and observations of onset of magnetospheric substorms. PhD Thesis, University of Helsinki, Finland
Pellinen, R.J., Heikkila, W.J. (1978a) Energization of charged particles to high energies by an induced substorm electric field within the magnetotail. J. Geophys. Res. 83:1544-1550
Pellinen, R.J., Heikkila, W.J. (1978b) Observations of auroral fading before breakup. J. Geophys. Res. 83:4207-4217
Pike, C.P., Whalen, J.A. (1974) Satellite observations of auroral substorms. J. Geophys. Res. 79:985-1000
Potemra, T. (1979) Current systems in the earth's magnetosphere. Rev. Geophys. Space Phys. 17:640-656
Pytte, T., McPherron, R.L., Kokubun, S. (1976) The ground signatures of the expansion phase during multiple onset substorms. Planet. Space Sci. 24:1115-1132
Ranta, H. (1978) The onset of an auroral absorption substorm. J. Geophys. Res. 83:3893-3899
Rostoker, G. (1968) Macrostructure of geomagnetic bays. J. Geophys. Res. 73:4217-4229
Rostoker, G., Bostrom, R. (1976) A mechanism for driving the gross Birkeland current configuration in the auroral oval. J. Geophys. Res. 81:235-244
Saito, T. (1969) Geomagnetic pulsations. Space Sci. Rev. 10:319-412
Sharber, R.J., Heikkila, W.J. (1972) Fermi acceleration of auroral particles, J. Geophys. Res. 77:3397-3410
Stauning, P. (1978) Compilation of lonlab riometer data for IMS-workshop in Bad Lauterberg, FRG in October 1978. lonlab report RSI, Danish Metereol. Institute, Techn. Univ., Lungby, Denmark
Swift, D.W. (1979) Auroral mechanisms and morphology. Rev. Geophys. Space Phys. 17:681-696
Untiedt, J., Pellinen, R.J., Kuppers, F., Opgenoorth, H.J., Pelster, W.D., Baumjohann, W., Ranta, H., Kangas, J., Czechowsky, P., Heikkila, W.J. (1978) Observations of the initial development of an auroral and magnetic substorm at magnetic midnight. J. Geophys. 45:41-65
Vallance Jones, A. (1976) Aurora. Dordrecht, Boston: D. Reidel Publ. Comp.
Wedeken, U., Hillebrand, O., Krenzien, E., Ranta, A., Ranta H., Voelker, H. (1979) Cosmic noise absorption events and geomagnetic pulsations activity during substorms. J. Geophys. 46:249-259
Wescott, E.M., Stenbaek-Nielsen, H.C., Davis, T.N., Murcray, W.B., Peek, H.M., Bottoms, P.J. (1975) The L=6.6 Oosik Barium plasma injection experiment and magnetic storm on March 7, 1972. J. Geophys. Res. 80:951-966
Whalen, J.A. (1970) Auroral oval plotter and nomograph for determining corrected geomagnetic local time, latitude, and longitude for high latitudes in the northern hemisphere. Environmental Res. Papers No. 327, Air Force Cambridge Res. Lab., Bedford, Mass.
Akasofu, S.-I. (1974) A study of auroral displays photographed from the DMSP-2 satellite and from the Alaska meridian chain of stations. Space Sci. Rev. 16:617-725
Akasofu, S.-I. (1977) Physics of magnetospheric substorms. Dorndrecht, Boston: Reidel Publ. Comp.
Akasofu, S.-I., Eather, R.H., Bradbury, J.N. (1969) The absence of the Hydrogen emission H|beta in the westward traveling surge. Planet. Space Sci. 17:1409-1412
Akasofu, S.-I., Kimball, D.S., Meng, Ch.-I. (1965a) The dynamics of the aurora II: westward traveling surges. J. Atmos. Terr. Phys. 27:173-187
Akasofu, S.-I., Kimball, D.S., Meng, Ch.-I. (1965b) The dynamics of the aurora V: Poleward motions. J. Atmos. Terr. Phys. 27:497-503
Atkinson, G. (1971) Magnetosphere flows and substorms, In: Proceedings of Advanced Study Inst. on Magnetosphere Ionosphere Interactions, Dalseter, Norway
Bannister, J.R., Gough, D.I. (1977) Development of a polar magnetic substorm: A two-dimensional magnetometer array study. Geophys. J. R. Astron. Soc. 51:75-90
Bannister, J.R., Gough, D.I. (1978) A study of two polar magnetic substorms with a two-dimensional magnetometer array. Geophys. J. R. Astron. Soc. 53:1-26
Baumjohann, W. (1979) Spatially inhamogeneous current configurations as seen by the Scandinavian magnetometer array. In: Proceedings of the International Workshop on Selected Topics of Magnetospheric Physics. Tokyo, March
Baumjohann, W., Greenwald, R.A., Kuppers, F. (1978) Joint magnetometer array and radar backscatter observations of auroral currents in northern Scandinavia. J. Geophys. 44:373-383
Bostrom, R. (1964) A Model of the auroral electrojets. J. Geophys. Res. 69:4983-4999
Bostrom, R. (1977) Current systems in the magnetosphere and ionosphere. In: Brekke, A. (Ed.) Radar probing of the auroral plasma, Proc. EISCAT Summer School, Tromso, Norway, June 5-13 1975, Universitatsfortlaget, Tromso-Oslo-Bergen
Boyd, J.S., Belon, A.E., Romick, G.J. (1971) Latitude and time variations in precipitated electron energy inferred from measurements of auroral heights. J. Geophys. Res. 76:7694-7700
Brekke, A., Doupnik, J.R., Banks, P.M. (1974) Incoherent scatter measurements of E region conductivities and currents in the auroral zone. J. Geophys. Res. 79:3773-3789
Clauer, C.R., McPherron, R.L. (1974) Mapping the local time - universal time development of magnetospheric substorms using midlatitude observations. J. Geophys. Res. 79:2811-2820
Eather, R.H. (1979) DMSP calibration. J. Geophys. Res. 84:4134-4144
Fukunishi, H. (1975) Dynamic relationship between proton and electron auroral substorms. J. Geophys. Res. 80:553-574
Fukushima, N. (1974) Equivalent current pattern for a field-aligned current into the auroral belt of enhanced electric conductivity, Part I: Case of no charge accumulation at the auroral-zone boundaries. Rep. Ionos. Space Res. Jpn. 28:207-213
Fukushima, N. (1975a) Equivalent current pattern for a field-aligned current into the auroral belt of enhanced electric conductivity, Part II: Case of charge accumulation at the auroral-zone boundaries. Rep. Ionos. Space Res. Jpn. 29:31-38
Fukushima, N. (1975b) Equivalent current pattern for a field-aligned current into the auroral belt of enhanced electric conductivity, Part III: Case of open field lines on the poleward side and closed field lines on the equatorward side of the auroral belt. Rep. Ionos. Space Res. Jpn. 29:39-46
Fukushima, N. (1976) Generalized theorem for no ground magnetic effect of vertical currents connected with Pedersen currents in the uniform-conductivity ionosphere. Rep. Ionos. Space Res. Jpn. 30:35-40
Greenwald, R.A., Weiss, W., Nielsen, E., Thomson, N.R. (1978) Stare, a new radar auroral backscatter experiment in northern Scandinavia. Radio Sci. 13 (In press)
Gustafsson, G. (1970) A revised corrected geomagnetic coordinate system. Ark. Geotys. 5:595-617
Harang, L. (1946) The mean field of disturbance of polar geomagnetic storms. Terr. Magn. Atmos. Electr. 51:353-380
Heikkila, W.J., Pellinen, R.J. (1977) Localized induced electric field within the magnetotail. J. Geophys. Res. 82:1610-1614
Heppner, J.P. (1954) Time sequences and spatial relations in auroral activity during magnetic bays at College, Alaska. J. Geophys. Res. 59:329-338
Hypponen, M., Pellinen, R.J., Sucksdorff, C., Torniainen, R. (1974) Digital all-sky camera. Technical report No. 9, Finnish Metereol. Inst.
Iijima, T., Potemra, T.A. (1976) The amplitude distribution of fieldaligned currents at northern high latitudes observed by Triad. J. Geophys. Res. 81:2165-2174
Kamide, Y., Akasofu, S.-I. (1975) The auroral electrojet and global auroral features. J. Geophys. Res. 80:3585-3602
Kamide, Y., Rostoker, G. (1977) The spatial relationship of fieldaligned currents and auroral electrojets to the distribution of nightside auroras. J. Geophys. Res. 76:5589-5608
Kamide, Y., Akasofu, S.-I., Deforest, S.E., Kisabeth, J.L. (1975) Weak and intense substorms. Planet. Space Sci. 23:579-587
Kisabeth, J.L. (1972) The dynamical development of the polar electrojets. Edmonton: PhD Thesis, University of Alberta
Kisabeth, J.L., Rostoker, G. (1971) Development of the polar electrojet during polar magnetic substorms. J. Geophys. Res. 76:6815-6828
Kisabeth, J.L., Rostoker, G. (1973) Current flow in auroral loops and surges inferred from ground-based magnetic observations. J. Geophys. Res. 78:5573-5584
Kisabeth, J.L., Rostoker, G. (1974) The expansive phase of magnetospheric substorms. I. Development of the auroral electrojets and auroral arc configuration during a substorm. J. Geophys. Res. 79:972-984
Kisabeth, J.L., Rostoker, G. (1977) Modelling of the three-dimensional current systems associated with magnetospheric substorms. Geophys. J.R. Astrom. Soc. 49:655-683
Klumpar, D.M. (1979) Relationship between auroral particle distributions and magnetic field perturbations associated with fieldaligned currents (accepted for publication). J. Geophys. Res.
Klumpar, D.M., Burrows. J.R., Wilson, M.D. (1976) Simultaneous observations of field-aligned currents and particle fluxes in the post-midnight sector. Geophys. Res. Lett. 3:395-398
Kuppers, F., Untiedt, J., Baumjohann, W., Lange, K., Jones, A.G. (1979) A two-dimensional magnetometer array for groundbased observations of auroral zone electric currents during the International Magnetospheric Study (IMS). J. Geophys. 46:429-450
Lui, A.T.Y., Venkatesan, D., Anger, C.D., Akasofu, S.-I., Heikkila, W.J., Winningham, J.D., Burrows, J.R. (1977) Simultaneous Observations of particle precipitations and auroral emissions by the ISIS 2 satellite in the 19-24 MLT sector. J. Geophys. Res. 82:2210-2226
Maurer, H., Theile, B. (1978) Parameters of the auroral electrojet from magnetic variations along a meridian. J. Geophys. 44:415-426
McPherron, R.L. (1970) Growth phase of magnetospheric substorms. J. Geophys. Res. 75:5592-5599
McPherron, R.L. (1979) Magnetospheric substorms. Rev. Geophys. Space Phys. 17:657-681
McPherron, R.L., Russel, C.T., Aubry, M.P. (1973) Satellite studies of magnetospheric substorms on August 15, 1968. 9. Phenomenological model for substorms. J. Geophys. Res. 79:3131-3149
Mozer, F.S. (1971) Origin and effects of electric fields during isolated magnetospheric substorms. J. Geophys. Res. 76:7595-7608
Oguti, T., Fukunishi, H., Tohmatsu, T., Nagata, T (1974) H|beta -emissions during auroral breakup. Memoirs of National Inst. of Polar Research, Special Issue No. 3, Proceedings of antarctic review
meeting, 10-20
Opgenoorth, H.J. (1978) Vergleich von Strukturen im Polarlicht und im Magnetfeld gleichzeitiger lonospharenstrome. Diplomarbeit Physik, Inst. f. Geophys. Univ. Munster, FRG
Pellinen, R.J. (1979) Induction model and observations of onset of magnetospheric substorms. PhD Thesis, University of Helsinki, Finland
Pellinen, R.J., Heikkila, W.J. (1978a) Energization of charged particles to high energies by an induced substorm electric field within the magnetotail. J. Geophys. Res. 83:1544-1550
Pellinen, R.J., Heikkila, W.J. (1978b) Observations of auroral fading before breakup. J. Geophys. Res. 83:4207-4217
Pike, C.P., Whalen, J.A. (1974) Satellite observations of auroral substorms. J. Geophys. Res. 79:985-1000
Potemra, T. (1979) Current systems in the earth's magnetosphere. Rev. Geophys. Space Phys. 17:640-656
Pytte, T., McPherron, R.L., Kokubun, S. (1976) The ground signatures of the expansion phase during multiple onset substorms. Planet. Space Sci. 24:1115-1132
Ranta, H. (1978) The onset of an auroral absorption substorm. J. Geophys. Res. 83:3893-3899
Rostoker, G. (1968) Macrostructure of geomagnetic bays. J. Geophys. Res. 73:4217-4229
Rostoker, G., Bostrom, R. (1976) A mechanism for driving the gross Birkeland current configuration in the auroral oval. J. Geophys. Res. 81:235-244
Saito, T. (1969) Geomagnetic pulsations. Space Sci. Rev. 10:319-412
Sharber, R.J., Heikkila, W.J. (1972) Fermi acceleration of auroral particles, J. Geophys. Res. 77:3397-3410
Stauning, P. (1978) Compilation of lonlab riometer data for IMS-workshop in Bad Lauterberg, FRG in October 1978. lonlab report RSI, Danish Metereol. Institute, Techn. Univ., Lungby, Denmark
Swift, D.W. (1979) Auroral mechanisms and morphology. Rev. Geophys. Space Phys. 17:681-696
Untiedt, J., Pellinen, R.J., Kuppers, F., Opgenoorth, H.J., Pelster, W.D., Baumjohann, W., Ranta, H., Kangas, J., Czechowsky, P., Heikkila, W.J. (1978) Observations of the initial development of an auroral and magnetic substorm at magnetic midnight. J. Geophys. 45:41-65
Vallance Jones, A. (1976) Aurora. Dordrecht, Boston: D. Reidel Publ. Comp.
Wedeken, U., Hillebrand, O., Krenzien, E., Ranta, A., Ranta H., Voelker, H. (1979) Cosmic noise absorption events and geomagnetic pulsations activity during substorms. J. Geophys. 46:249-259
Wescott, E.M., Stenbaek-Nielsen, H.C., Davis, T.N., Murcray, W.B., Peek, H.M., Bottoms, P.J. (1975) The L=6.6 Oosik Barium plasma injection experiment and magnetic storm on March 7, 1972. J. Geophys. Res. 80:951-966
Whalen, J.A. (1970) Auroral oval plotter and nomograph for determining corrected geomagnetic local time, latitude, and longitude for high latitudes in the northern hemisphere. Environmental Res. Papers No. 327, Air Force Cambridge Res. Lab., Bedford, Mass.