Abstract
The effect of solar wind on the relative abundances of galactic cosmic rays is assessed using the theories proposed by Parker1 and Dorman.2 The modulation factors for the ratios of electrons, deuterons, tritons and helium nuclei to protons, helium-3 to helium-4 and light (Z=3–5) to medium nuclei (Z=6–9) are presented.
The effect of the modulation on the differential energy spectra is studied. The form of the spectra, the position of the maximum in the spectra and the relative reduction over a solar cycle place a restriction on the parameters in the solar wind theory. Starting with plausible galactic spectra and by varying the parameters it is possible to fit the form of the solar minimum spectrum but it does not seem possible to produce the relative reduction between minimum and maximum throughout the energy range, with in the framework of the present solar wind theory.
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References
Parker, E. N...Phys. Rev., 1958,110, 1445;Interplanetary Dynamical Processes, Interscience Publishers, New York (1963).
Dorman, L. I...Proceedings of the International Conference on Cosmic Rays Moscow, 1960,4, 320.
Webber, W. Review articleProgress in Elementary Particle and Cosmic Ray Physics, North Holland Publishing Company, Amsterdam, 1962,6.
Apparao, M. V. K. and Kaplon, M. F.Nuovo Cim., 1963,27, 700.
Apparao, M. V. K. ..Ibid. (In print).
Bryant, D. A., Cline, T. L., Desai, U. D. and McDonald, F. B.J. Geophys. Research, 1962,67, 4983.
Apparao, M. V. K. .. (To be published).
McDonald, F. B...Phys. Rev., 1959,116, 462.
—————..J. Phys. Soc. Japan, 1962,17, Suppl. A-II, 428.
Aizu, H., Fujimoto, Y., Hasegawa, S., Koshiba, M., Mito, I., Nishimura, J., Yokoi, K. and Shein, M.Phys. Rev., 1959,116, 436.
Engler, A., Foster, F., Green, T. L. and Mulvey, J.Nuovo Cim., 1961,20, 1157.
Frier, P. S., Ney, E. P. and Waddington, C. J.Phys. Rev., 1959,114, 365.
Fichtel, C. E., Guss, D. E., Stevenson, G. R. and Waddington, C. J. ——Ibid., 1964,133 B, 818.
Waddington, C. J. .. Private Communication.
Fichtel, C. E., Guss, D. E., Kniffen, D. A. and Neelakantan, K. A.Proceedings of the International Conference on Cosmic Rays, Jaipur, 1963,2.
Apparao, M. V. K. and Ramadurai, S.J. Geophys. Research,69, 3729 (1964).
————— and Lavakare, P. J.Nuovo Cim., 1962,26, 740.
Aizu, H., Mito, I., Fujimoto, Y., Hasegawa, S., Koshiba, M., Nishimura, J. and Yokoi, K.J. Phys. Soc. Japan, 1962,17, Suppl. A-III, 38.
O’Dell, F. W., Shapiro, M. M. and Stiller, B. ——Ibid., 1962,17, Suppl. A-III, 23.
Apparao, M. V. K., Dahanayake, C., Kaplon, M. F. and Lavakare, P. J.Proceedings of the International Conference on Cosmic Rays, Jaipur, 1963,3.
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Communicated by Dr. M. G. K. Menon,f.a.sc.
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Apparao, K., Ramadurai, S. Modulation of galactic cosmic radiation in interplanetary space by the solar wind. Proc. Indian Acad. Sci. 61, 237–254 (1965). https://doi.org/10.1007/BF03046359
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DOI: https://doi.org/10.1007/BF03046359