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Rotation and Flattening of Globular Clusters

Published online by Cambridge University Press:  04 August 2017

S. Michael Fall
Affiliation:
Institute of Astronomy, Madingley Road, Cambridge CB3 OHA England Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 USA
Carlos S. Frenk
Affiliation:
Astronomy Centre, University of Sussex, Falmer, Brighton BN1 9QH England Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 USA

Extract

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Pease and Shapley (1917) first remarked on the apparent flattening of several Galactic globular clusters, a view that has been confirmed by many subsequent studies. Tidal stresses, internal rotation, and velocity anisotropies can cause deviations from sphericity in stellar systems. In general, we might expect globular clusters to have some angular momentum at the time of formation and, if they collapsed from flattened initial conditions, to have anisotropic pressure support. Since the velocity distributions within the clusters can be altered by a variety of internal and external processes, their shapes are expected to evolve. In this article, we review the methods for measuring ellipticities and the results that have emerged from such studies. Our main purpose, however, is to discuss the processes that determine the shapes of globular clusters and the ways in which they change with time.

Type
May 30: Model System in the Point-Mass Approximation
Copyright
Copyright © Reidel 1985 

References

Aarseth, S.J. 1966, M.N.R.A.S., 132, 35.Google Scholar
Aarseth, S.J. 1984, in Methods of Computational Physics, eds. Brackbill, J.U. and Cohen, B.I. (New York: Academic Press), p. 1.Google Scholar
Aarseth, S.J. and Binney, J. 1978, M.N.R.A.S. 185, 227.Google Scholar
Agekian, T.A. 1958, Soviet Astr. - A.J., 2, 22.Google Scholar
Binney, J. 1978, M.N.R.A.S., 183, 501.Google Scholar
Chandrasekhar, S. 1969, Ellipsoidal Figures of Equilibrium (New Haven: Yale University Press).Google Scholar
Chun, M.S. 1978, A.J., 83, 1062.Google Scholar
Cohn, H. 1980, Ap. J., 242, 765.CrossRefGoogle Scholar
Cudworth, K.M. 1979, A.J., 84, 1312.CrossRefGoogle Scholar
Elson, R.A.W. and Freeman, K.C. 1984, Ap. J., submitted.Google Scholar
Fall, S.M. and Frenk, C.S. 1983, A.J., 88, 1626.Google Scholar
Fall, S.M. and Frenk, C.S. 1984, in preparation.Google Scholar
Freeman, K.C. and Da Costa, G. 1984, in preparation.Google Scholar
Freeman, K.C., Illingworth, G., and Oemler, A. 1983, Ap. J., 272, 488.Google Scholar
Freeman, K.C. and Seitzer, P. 1984, in preparation. Google Scholar
Frenk, C.S. and Fall, S.M. 1982, M.N.R.A.S., 199, 565.Google Scholar
Geisler, D. and Hodge, P. 1980, Ap. J., 242, 66.Google Scholar
Geyer, E.H., Hopp, U., and Nelles, B. 1983, Astr. Ap., 125, 359.Google Scholar
Geyer, E.H. and Richtler, T. 1981, in Astrophysical Parameters for Globular Clusters, eds. Philip, A.G.D. and Hayes, D.S. (Schenectady: L. Davis Press), p. 239.Google Scholar
Goodman, J. 1983, Ph.D. Thesis, Princeton University.Google Scholar
Gunn, J.E. and Griffin, R.F. 1979, A.J., 84, 752.CrossRefGoogle Scholar
Harris, W.E., Racine, R., and deRoux, J. 1976, Ap. J. Suppl. 31, 13.Google Scholar
Hodge, P.W. 1983, Ap. J., 264, 470.Google Scholar
Kholopov, P.N. 1953, Publ. Astr. Sternberg Inst., 23, 250.Google Scholar
King, I. 1961, A.J., 66, 68.Google Scholar
Lupton, R., Gunn, J.E., and Griffin, R.F. 1984, in preparation.Google Scholar
Mayor, M. et al. 1984, Astr. Ap., 134, 118.Google Scholar
Meylan, G. and Mayor, M. 1984, preprint.Google Scholar
Pease, F.G. and Shapley, H. 1917, Contr. Mt. Wilson Obs., 129.Google Scholar
Searle, L., Wilkinson, A., and Bagnuolo, W.G. 1980, Ap. J. 239, 803.Google Scholar
Shapiro, S.L. and Marchant, A.B. 1976, Ap. J., 210, 757.Google Scholar
Shapley, H. 1930, Star Clusters (New York: McGraw-Hill).Google Scholar
Shapley, H. and Sawyer, H. 1927, Harvard Obs. Bull., 852.Google Scholar
Spitzer, L. 1956, Physics of Fully Ionized Gases (New York: Inter-Science).Google Scholar
Spitzer, L. 1975, in Dynamics of Stellar Systems, ed. Hayli, A. (Dordrecht: Reidel), p. 3.Google Scholar
van den Bergh, S. 1983, P.A.S.P., 95, 839.CrossRefGoogle Scholar
van den Bergh, S. 1984, Observatory, in press.Google Scholar
White, S.D.M. 1978, M.N.R.A.S., 184, 185.Google Scholar