154 day solar periodicity

spaceweb@oulu.fi - last update: 22 December 1998, 2020 UT (RR)

The 154 day periodicity in the Sun was first reported on gamma-ray flares (Rieger et al., 1984). Later the same periodicity has been found in many other paremeters related to Sun and solar wind/IMF, although it does not seem to be a persistent periodicity, and the exact period varies between 140 and 170 days. For example, Cane et al. (1998) found a 153 day periodicity in IMF strength for solar maximum years 1978-1982, but not for the preceeding or subsequent solar cycles.

Variables showing ~154 day periodicity
Variable	Reference
Flare related	Rieger et al., 1984; Bai and Cliver, 1990; Bai and Sturrock, 1993
Active region parameters (sunspot areas etc.)	Lean and Brueckner, 1989; Lean, 1990
F10.7	Lean and Brueckner, 1989
IMF strength and solar wind velocity	Cane et al., 1998

References

Bai, T., and E. W. Cliver, A 154 day periodicity in the occurrence rate of proton flares, Astrophys. J., 363, 299, 1990.
Bai, T., and P. A. Sturrock, Evidence for a fundamental period of the Sun and its relation to the 154 day complex of periodicities, Astrophys. J., 409, 476, 1993.
Cane, H. V., I. G. Robinson, and T. T. von Rosenvinge, Interplanetary magnetic field periodicity of ~ 153 days, Geophys. Res. Lett., 25, 4437-4440, 1998.
Lean, J. L., Evolution of the 155 day periodicity in the sunspot areas during solar cycles 12 to 22, Astrophys. J., 363, 718, 1990.
Lean, J. L., and G. E. Brueckner, Intermediate-term solar periodicities: 100-500 days, Astrophys. J., 337, 568, 1989.
Rieger, E., G. H. Share, D. J. Forrest, G. Kanbach, C. Reppin, and E. L. Chupp, A 154-day periodicity in the occurrence of hard solar flares, Nature, 312, 623, 1984.