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Pulsar Models

  • W. J. Cocke
  • Jeffrey M. Cohen

Abstract

In this article we examine the possibility, previously considered by others, that the pulsed radio sources observed recently are pulsating white dwarfs. We first present the results of radial mode eigenvalue calculations (for various central densities and compositions) which were obtained by integrating the eigenvalue equations themselves rather than by using variational techniques. Computations of non-linear white dwarf pulsations are then presented, in which a hydrodynamic code was used to follow pulsations of finite amplitude driven by pycno-nuclear reactions. Very large amplitude pulsation of neutron stars is also considered. The possibility that the optical pulsation periods are twice as long as the radio periods has arisen from observations1. We discuss a method for such a “frequency doubling” based partly on magnetohy drodynamics.

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Copyright information

© Springer Science+Business Media New York 1968

Authors and Affiliations

  • W. J. Cocke
    • 1
  • Jeffrey M. Cohen
    • 1
  1. 1.Institute for Space StudiesGoddard Space Flight CenterNew York

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