Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-13T12:20:42.168Z Has data issue: false hasContentIssue false

The non-radial propagation of coronal streamers in minimum activity epoch

Published online by Cambridge University Press:  26 February 2010

Andrey G. Tlatov
Affiliation:
Kislovodsk Mountain Station, The Central Astronomical Observatory of RAS at Pulkovo, 357700, Box-145, Gagarina st., 100, Kislovodsk, Russia email: tlatov@mail.ru
Valeria V. Vasil'eva
Affiliation:
Kislovodsk Mountain Station, The Central Astronomical Observatory of RAS at Pulkovo, 357700, Box-145, Gagarina st., 100, Kislovodsk, Russia email: tlatov@mail.ru
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We have analyzed the shape of the solar corona using the data of daily observations with Mark-3/4 (1980-2008) and SOHO/Lasco-2 (1996–2008) telescopes. The angles of deviation of coronal rays from the radial direction Δθ vary cyclically, reaching the maximum deviation towards the solar equator at the minimum of the solar activity. At the minimum of the 24-th cycle of activity, the Δθ angles were smaller than they were at the minimum of the 22-nd and 23-rd cycles.

We also analyzed of the solar structure corona during eclipses for minimum activity from 1870 till 2008. We examined changes in the index, which characterizes the angle of large coronal streamers to the equatorial plane. It has been shown that the index has been smoothly changing during the last 140 years. The maximal value of an index was during 17–19 activity cycles. The minimal values are reached in the end of 19 centuries and at the present time.

We consider the relations between the angles of deviation of coronal rays at the minimum of activity, the parameters of the global magnetic field of the Sun, and the amplitude of the subsequent cycle of activity, and discuss the hypothesis that the variations of the inclination of coronal rays may affect the parameters of the solar wind and the indices of geomagnetic perturbations at the minima of the solar activity cycles.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2010

References

Eselevich, V. G. & Eselevich, M. V. 2002, Solar Phys., 208, 5CrossRefGoogle Scholar
Kim, G.-D., Makarov, V. I., & Tlatov, A. G. 2004, International Journal of Geomagnetism and Aeronomy, 5, 2, GI2011CrossRefGoogle Scholar
Loucif, M. L. & Koutchmy, S. 1989, ApJS, 77, 44Google Scholar
Nikolskiy, G. M. 1955, Astron. Lett., 160, 11Google Scholar
Ohl, A. I. 1966, Solnycnye Danie, N9, 84Google Scholar
Tlatov, A. G. 2009,Solar Phys., in presGoogle Scholar
Vsekhsvyatsky, S. K., Nikolsky, G. M., Ivanchuk, V. I., Nesmuanovich, A. T., Ponomarev, E. A., Rubo, G. A., & Cherednichenko, V. I. 1965, The Solar Corona and Corpuscular Emission in Interplanetary Space (Kiev Univers. Press, Kiev), 293 ppGoogle Scholar
Wang, Y.-M. 1996, Apj, 456, L119Google Scholar