Abstract
The ‘EPAC’ instrument on Ulysses is sensitive to relativistic cosmic rays when far from Jupiter and in the absence of energetic solar particles. Measurement of the latitude gradient of these particles, after correction for time variations, has been made for the 1993–1994 south polar pass. The average magnitude of the gradient is about the same or smaller than predicted by a model which includes full gradient drift. However, the latitude dependence of the solar plasma output into interplanetary space (including fast-stream and magnetic turbulence effects) seems to be important in determining the magnitude of modulation.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Fillius, W. F.: 1991, Proc. 22nd Int. Cosmic Ray Conf., Dublin 3, 394.
Jokipii, J. R. and Kopriva, G. A.: 1979, Astrophys. J. 234, 746.
Jokipii, J. R. and Kota, J.: 1989, Geophys. Res. Letters 16, 1.
Keppler, E., Blake, J. B., Hovestadt, D., Korth, A., Quenby, J. J., Umlauft, G., and Woch, J.: 1992, Astron. Astrophys. Suppl. Ser. 92, 317.
Keppler, E., Franz, M., Korth, A., Reuss, M. K., Blake, J.B., Seidel, R., Quenby, J. J., and Witte, M.: 1995, Science, accepted.
Kleckler, B., Hovestadt, D., Scholer, M., Arbinger, H., Erll, M., Kaestle, H., Kuenneth, E., Laeverenz, P., Seidenschlwang, E., Blakem, J. B., Katz, N., and Mabry, D.: 1993, IEEE Transactions Science Remote Sensing 31, 542.
McDonald, F.B., Lul, N., Traimor, J.H., von Hollebecke, M. R., and Webber, W. R.: 1981, Astrophys. J. 249, L71.
Potgieter, M. S. and Haasbroek, L. J.: 1993, Proc. 23rd Int. Cosmic Ray Conf. 3, 457.
Potgieter, M. S. and LeRoux, J. A.: 1989, Astron. Astrophys. 209, 400.
Potgieter, M. S., LeRoux, J.A., and Burger, R. A.: 1987, Proc. 20th Int. Cosmic Ray Conf. 3, 287.
Quenby, J. J. and Lietti, B.: 1968, Planetary Space Sci. 16, 1209.
Quenby, J. J., Lockwood, J. A., and Webber, W. R.: 1990, Astrophys. J. 365, 365.
Reinecke, J. P. L. and Moraal, H.: 1993, Proc. 23rd Int. Cosmic Ray Conf., Calgary 3, 473.
Reinecke, J. P. L., Moraal, H., and McDonald, F. B.: 1991, Proc. 22nd Int. Cosmic Ray Conf. 3, 517.
Sarabhai, V. and Subramanyan, G.: 1965, Proc. 9th Int. Cosmic Ray Conf. 204.
Simpson, J. et al.: 1992, Astron. Astrophys. Suppl. Series 92, 363.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Quenby, J.J., Drolias, B., Keppler, E. et al. A ‘Ulysses’ cosmic-ray latitude gradient observation and modulation models. Sol Phys 163, 397–403 (1996). https://doi.org/10.1007/BF00148010
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00148010