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Magnetic Activity and Rotation in Brown Dwarfs and Low Mass Stars

Published online by Cambridge University Press:  26 May 2016

Gibor Basri  and
Subanjoy Mohanty
Gibor Basri
Affiliation:
Astronomy Department, MC3411, University of California, Berkeley, 94705, USA
Subanjoy Mohanty
Affiliation:
Astronomy Department, MC3411, University of California, Berkeley, 94705, USA

Abstract

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One of the triumphs of the last 2 decades has been the establishment of the relation between stellar rotation and magnetic activity in solar-type stars. Rapid rotation produces strong activity, which in turn provides magnetic braking to reduce rotation. A solar-type dynamo cannot operate in fully convective stars, so it is of interest to study mid and late M stars. Hints that a dramatic change occurs in very low-mass stars and substellar objects appeared in 1995. The past 7 years have seen substantial progress on this question, with the conclusion that the rotation-activity connection indeed breaks down. As one goes to the bottom of the main sequence and below, the amount of magnetic activity takes a sudden fall, with a concomitant increase in the spindown times of the objects. We summarize these results, and some theoretical work which helps explain them. We also present some remaining mysteries, such as why very young objects seem excessively active, and flaring in objects with no other signs of magnetic activity.

Type
Part 8. Activity and Weather
Information
Symposium - International Astronomical Union , Volume 211: Brown Dwarfs , 2003 , pp. 427 - 435
Copyright
Copyright © Astronomical Society of the Pacific 2001 

References

Allard, F., Hauschildt, P.H., Alexander, D.R., Tamanai, A., Schweitzer, A., 2001, ApJ, 556, 357 Google Scholar
Basri, G. 2000, Eleventh Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, A.S.P. CS-223, García-López, , Rebolo, , Zapatero-Osorio, (eds.), 261 Google Scholar
Basri, G. & Marcy, G.W. 1995, AJ, 109, 762 Google Scholar
Basri, G., Oppenheimer, B.R., Kulkarni, S., Nakajima, T. & Marcy, G.W. 1996, Ninth Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, A.S.R CS-109, Pallavicini, , (ed.), 587 Google Scholar
Berger, E. 2002, ApJ, 572, 503 Google Scholar
Charbonneau, P., Schrijver, C.J., Macgregor, K.B., 1997, Cosmic Winds and the Heliosphere, (Jokipii, J.R., Sonett, C.P., Giampapa, M.S., eds.) (Univ. of Arizona Press)Google Scholar
Comerón, F., Neuhaüser, R. & Kaas, A.A. 2000, A&A, 359, 269 Google Scholar
Delfosse, X., Forveille, T., Perrier, C., Mayor, M., 1998, A&A, 331, 581 Google Scholar
Fleming, T.A., Schmitt, J.H.M.M. & Giampapa, M.S. 1995, ApJ, 450, 401 Google Scholar
Fleming, T.A., Giampapa, M.S. & Schmitt, J.H.M.M. 2000, ApJ, 533, 372 Google Scholar
Gizis, J.E., Monet, D.G., Reid, I.N., Kirkpatrick, J. D., Liebert, J. & Williams, Rik J. 2000, AJ, 120, 1085 Google Scholar
Gizis, J.E., Reid, I.N. & Hawley, S.L. 2002, AJ, 123, 3356 Google Scholar
Hawley, S.L., Gizis, J.E. & Reid, I.N. 1996, AJ, 112, 2799 Google Scholar
James, D. J., Jardine, M. M., Jeffries, R. D., Randich, S., Collier Cameron, A. & Ferreira, M. 2000, MNRAS, 318, 1217 Google Scholar
Kraft, R.P. 1967, ApJ, 150, 551 Google Scholar
Linsky, J.L., Wood, B.E., Brown, A., Giampapa, M.S. & Ambruster, C. 1995, ApJ, 455, 670 Google Scholar
Martín, E.L. & Ardila, D. 2001, AJ, 121, 2758 Google Scholar
Meyer, F. & Meyer-Hofmeister, E. 1999, A&A, 341, L2 Google Scholar
Mohanty, S., Basri, G., Shu, F., Allard, F. & Chabrier, G. 2002, ApJ, 571, 469 Google Scholar
Mohanty, S. & Basri, G. 2002, ApJ, submitted (check astro-ph) Google Scholar
Noyes, R.W., Hartmann, L.W., Baliunas, S.L., Duncan, D.K. & Vaughan, A.H. 1984, ApJ, 279, 763 Google Scholar
Reid, I.N., Kirkpatrick, J.D., Gizis, J.E. & Liebert, J. 1999, ApJ, 527, L105 Google Scholar
Reid, I.N., Kirkpatrick, J.D., Liebert, J., Gizis, J.E., Dahn, C.C. & Monet, D.G. 2002, AJ, 124, 519 Google Scholar
Rutledge, R.E., Basri, G., Martín, E.L. & Bildsten, L. 2000, ApJ, 538, L141 Google Scholar
Tinney, C.G. & Reid, I.N. 1998, MNRAS, 301, 1031 CrossRefGoogle Scholar