Hydrodynamic model of torsional oscillations of the Sun

1Loginov, AA, 1Cheremnykh, OK, 2Krivodubskij, VN, 1Salnikov, NN
1Space Research Institute of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine, Kyiv, Ukraine
2Astronomical Observatory of the Taras Shevchenko National University of Kyiv, Kyiv, Ukraine
Kosm. nauka tehnol. 2012, 18 ;(1):74–81
Section: Space Astronomy
Publication Language: Russian
Hydrodynamic nature of solar torsional oscillations is justified on the basis of comparison of observational results with some results of our numerical simulations of global flows in the solar convection zone. These oscillations are shown to be a toroidal component of the global three-dimensional oscillatory flow which is equator asymmetric. Physical mechanism of torsional oscillations is the loss of stability of the solar differential rotation.
Keywords: Sun, torsional oscillations
1. Allen C.W. Astrophysical Quantities, 448 p. (Moscow, 1977) [in Russian].
2. Batchelor G. K. An Introduction to Fluid Dynamics, 760 p. (Moscow, 1973) [in Russian].
3. Vitinskij Yu. I. Cyclic recurrence and solar activity forecasts, 260 p. (Moscow, 1973) [in Russian].
4. Vitinskij Ju. I., Kopeckij M., Kuklin G. V. Statistics of spot forming activity of the Sun, 296 p. (Moscow, 1986) [in Russian].
5. Gledzer E. B., Dolzhanskij F. V., Obuhov A. M. Systems of hydrodynamic type and their use, 368 p. (Moscow, 1981) [in Russian].
6. Joseph D. D. Stability of fluid motions, 638 p. (Moscow, 1981) [in Russian].
7. Kochin N. E., Kibel' I. A., Roze N. V. Theoretical Hydro Mechanics, Pt. 1, 584 p. (Moscow, 1963) [in Russian].
8. Loginov A. A., Sal'nikov N. N., Cheremnykh O. K., et al. On hydrodynamical mechanism of generation of global poloidal flow of the Sun Kinematics Phys. Celestial Bodies, 27 (5), 3—11 (2011) [in Russian].
9. Loginov A. A., Salnikov N. N., Cheremnykh O. K., et al. Hydrodynamic model for generation of global poloidal flow of the Sun,  Kosm. nauka tehnol., 17 (1), 29—35 (2011) [in Russian].
10. Priest E. R. Solar Magnetohydrodynamics, 592 p. (Moscow, 1985) [in Russian].
11. Rubashev B. M. Problems of solar activity, 364 p. (Moscow; Leningrad, 1964) [in Russian].
12. Antia H. H., Basu S.  ESA SP-259: SOHO 14: Helio- and asteroseismology: towards a golden future, P. 305—308 (2004).
13. Braun D. C., Birc A. C. Prospects for the detection of the deep solar meridional circulation, Astrophys. J. Lett., 689, L161—L165 (2008).
14. Couette M. Etudes sur le frottement des liquides, Ann. Chem. Phis., 21, P. 433 (1890).
15. Howard R., LaBonte B. J. The Sun is observed to be a torsional oscillator with a period of 11 years,  Astrophys. J., 239, L33—L36 (1980).
16. Howe R., Christensen-Dalsgaard J., Hill F., et al. Dynamics variations at the base of the solar convection zone, Science, 287, 2456—2460 (2000).
17. Howe R., Christensen-Dalsgaard J., Hill F., et al. Deeply penetrating banded zonal flow in the solar convection zone, Astrophys. J., 533, L163—166 (2000).
18. Howe R., Christensen-Dalsgaard J., Hill F., et al. Solar convection-zone dynamics, 1995—2004, Astrophys. J., 634, 1405—1415 (2005).
19. Howe R., Christensen-Dalsgaard J., Hill F., et al. Temporal variations in solar rotation at the bottom of the convection zone: The current status,  Adv. Space Res., 40 (7), 915—918 (2007).
20. Howe R., Christensen-Dalsgaard J., Hill F., et al. A note on the torsional oscillation at solar minimum,  Astrophys. J. Lett., 702, L87—L89 (2009).
21. Howe R., Komm R., Hill F., et al. Rotation-rate variations at tachocline: An update,  J. Phys: Conf. Ser., 271 (1), P. 012075 (2011).
22. Komm R., Howe R., Hill F., et al. Solar-cycle variation of zonal and meridional flow, J. Phys: Conf. Ser., 271 (1), P. 012077 (2011).
23. Kosovichev A.G. Probing solar and stellar interior dynamics and dynamo,  Adv. Space Res., 41, 830—837 (2008).
24. Kosovichev A. G., Schou J. Detection of zonal shear flows beneath the Sun’s surface from f-mode frequency splitting,  Astrophys. J., 482, P. L207 (1997).
25. Maunder E. W. Note on the distribution of Sun-spots in heliographic latitude, 1874 to 1902,  Mon. Notic. Roy. Astron. Soc., 64, 747—761 (1904).
26. Maunder E. W. Distribution of sunspots in heliographic latitude, 1874—1913,  Mon. Notic. Roy. Astron. Soc., 74, 112—116 (1913).
27. Schove D. J. The Sunspot Cycle, 649 B.C. to A.D. 2000,  J. Geophys. Res. — 1955. — 60. — P. 127—146.
28. Thompson M. J., Christensen-Dalsgaard J., Miesch M. S., Toomre J. The internal rotation of the Sun,  Annu. Rev. Astron. and Astrophys.,  41, 599—643 (2003).

29. Vorontsov S. V., Christensen-Dalsgaard J., Schou J., et al. Helioseismic measurement of solar torsional oscillations, Science, 296, P. 101—103 (2002).