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Learning about Stellar Dynamos from Long–term Photometry of Starspots

Published online by Cambridge University Press:  12 April 2016

Douglas S. Hall*
Affiliation:
Center of Excellence, Tenessee State University, Nashville, Tennessee 37203

Abstract

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Spottedness, as evidenced by photometric variability in 277 late-type binary and single stars, is found to occur when the Rossby number is less than about 2/3. This holds true when the convective turnover time versus B–V relation of Gilliland is used for dwarfs and also for subgiants and giants if their turnover times are twice and four times longer, respectively, than for dwarfs. Differential rotation is found correlated with rotation period (rapidly rotating stars approaching solid-body rotation) and also with lobe-filling factor (the differential rotation coefficient k is 2.5 times larger for F = 0 than F = 1). Also reviewed are latitude extent of spottedness, latitude drift during a solar-type cycle, sector structure and preferential longitudes, starspot lifetimes, and the many observational manifestations of magnetic cycles.

Type
Part IV Stellar activity
Copyright
Copyright © Springer-Verlag 1991

References

Baliunas, S.L., Vaughan, A.H.: 1985, Ann. Rev. Astr. Astrophys. 23, 379 Google Scholar
Bianchini, A.: 1988, I.B.V.S. 3136 Google Scholar
Bianchini, A.: 1990, Astron. J. 99, 1941 CrossRefGoogle Scholar
Catalano, S., Frisina, A., Rodonò, M.: 1980, I.A.U. Symposium 88, 405 Google Scholar
Doyle, J.G., Butler, C.J., Morrison, L.V., Gibbs, P.: 1988, Astron. Astrophys. 192, 275 Google Scholar
Eaton, J.A.. 1990, in Surface Inhomogeneities in Late-Type Stars, eds Byrne, P.B. and Mullan, D.F. (Berlin: Springer-Verlag), in pressGoogle Scholar
Eaton, J.A., Hall, D.S.: 1977, Astrophys. J. 227, 907 Google Scholar
Eaton, J.A., Poe, C.H.: 1985, B.A.A.S. 16, 914 Google Scholar
Gilliland, R.: 1985, Astrophys. J. 299, 286 CrossRefGoogle Scholar
Gray, D.F.: 1988, Lectures on Spectral Line Analysis of F, G, and K Stars, Arva, Ontario Google Scholar
Gray, D.F.: 1989a, Astrophys. J. 347, 1021 Google Scholar
Gray, D.F.: 1989b, Publ. Astron. Soc. Pac. 101, 695 Google Scholar
Hall, D.S.: 1987, Publ. Astr. Inst. Czechoslovakia 70, 77 Google Scholar
Hall, D.S.: 1989, I.A. U. Colloquium 107, 219.Google Scholar
Hall, D.S.: 1990a, Astron. J. 100, 554 Google Scholar
Hall, D.S.: 1990b, in Active Close Binaries, ed. Ibanoglu, C. (Dordrecht: Kluwer), p. 95.Google Scholar
Hall, D.S., Busby, M.R.: 1990, in Active Close Binaries, ed. Ibanoglu, C. (Dordrecht: Kluwer), p. 377.CrossRefGoogle Scholar
Hall, D.S., Gessner, S.E., Lines, H.C., Lines, R.D.: 1990a, Astron. J. 100, 2017 CrossRefGoogle Scholar
Hall, D.S., Henry, G.W.: 1990, in Active Close Binaries, ed. Ibanoglu, C. (Dordrecht: Kluwer), p. 287.CrossRefGoogle Scholar
Hall, D.S., Henry, G.W., Barksdale, W.S.: 1990b, in preparation.Google Scholar
Hall, D.S., Henry, G.W., Sowell, J.R.: 1990c, Astron. J. 99, 396 CrossRefGoogle Scholar
Hall, D.S., Strassmeier, K.G.: 1988, in Automatic Small Telescopes, eds. Hayes, D.S. and Genet, R.M. (Mesa: Fairborn Press), p. 71.Google Scholar
Olah, K., Hall, D.S., Henry, G.W.: 1990, in preparation.Google Scholar
Oskanyan, V.S., Evans, D.S., Lacy, C., McMillan, R.S.: 1977, Astrophys. J. 214, 430 Google Scholar
Percy, J.R., Sasselov, D.D., Alfred, A., Scott, G.: 1989, B.A.A.S. 21, 1117 Google Scholar
Rodonò, M:. 1986, in Cool Stars, Stellar Systems, and the Sun, eds. Zeilik, M. and Gibson, D.M. (Berlin: Springer-Verlag), p. 475.Google Scholar
Rodonò, M. et al. [22 authors]: 1986, Astron. Astrophys. 165, 135 Google Scholar
Scharlemann, E.T.: 1982, Astrophys. J. 253, 298 CrossRefGoogle Scholar
Strassmeier, K.G. 1989, in Remote Access Small Telescopes, eds. Hayes, D.S. and Genet, R.M. (Mesa: Fairborn Press), p. 223.Google Scholar
Strassmeier, K.G.: 1990, Astrophys. J. 348, 682 CrossRefGoogle Scholar
Strassmeier, K.G., Hall, D.S.: 1988, Astrophys. J. Suppl. 67, 453 Google Scholar
Strassmeier, K.G., Hall, D.S., Barksdale, W.S., Jusick, A.T., Henry, G.W.: 1990, Astrophys. J. 350, 367 Google Scholar
Strassmeier, K.G., Hall, D.S., Boyd, L.J., Genet, R.M.: 1989, Astrophys. J. Suppl. 69, 141 Google Scholar
Strassmeier, K.G., Hall, D.S., Zeilik, M., Nelson, E., Eker, Z., Fekel, F.C.: 1988, Astron. Astrophys. Suppl. 72, 291 Google Scholar
Tassoul, J.P.: 1987, Astrophys. J. 322, 857 Google Scholar
Tassoul, J.P.: 1988, Astrophys. J. 324, L71 Google Scholar
Wacker, S., Guinan, E.F.: 1987, I.B.V.S. 3018 Google Scholar
Zahn, J.P.: 1977, Astron. Astrophys. 57, 383 Google Scholar
Zeilik, M., De Blasi, C., Rhodes, M., Budding, E.: 1987, in Cool Stars, Stellar Systems, and the Sun, eds. Linsky, J.L. and Stencel, R.E. (Berlin: Springer-Verlag), p. 503.Google Scholar