Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-23T16:35:56.431Z Has data issue: false hasContentIssue false
  • English
  • Français

Magnetospheric Structure of Rotation-Powered Neutron Stars

Published online by Cambridge University Press:  27 September 2017

Jonathan Arons
Jonathan Arons*
Affiliation:
Astronomy Department and Physics Department, University of California at Berkeley, Institute of Geophysics and Planetary Physics, Lawrence Livermore National Laboratory

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

I survey recent theoretical work on the structure of the magnetospheres of rotation-powered pulsars, within the observational constraints set by their observed spindown, their ability to power synchrotron nebulae and their ability to produce beamed collective radio emission, while putting only a small fraction of their energy into incoherent X- and gamma radiation. I find no single theory has yet given a consistent description of the magnetosphere, but I conclude that models based on a dense outflow of pairs from the polar caps, permeated by a lower density flow of heavy ions, are the most promising avenue for future research.

Type
Part III Magnetospheric models
Information
International Astronomical Union Colloquium , Volume 128: Magnetospheric structure and emission mechanisms of radio pulsars , 1992 , pp. 56 - 77
Copyright
Copyright © United States Naval Observatory 1992

References

1 One can get around this to some extent by shortening the recurrence time for bursts in one object to be less than 30 years, yet longer than 10 years to avoid the observed lack of recurring flashes in most bursters (van Paradijs 1989). While not yet formally excluded, the chances are not large that this loophole is actually open.

2 More precisely, what keeps the star charged at the value expected for the filled magnetosphere?

3 Michel (1990) has recently suggested just this sort of model, in which the radio emission comes the electromagnetic fields associated with the narrow confinement of the pair discharges in the direction along the magnetic field. In my opinion, he has not paid sufficient attention to the fate of most of the energy in his model, which is in the dissipation of the discharge energy in γ-ray emission and thermal radiation from the neutron star, both with luminosities comparable to IΩ.

4 These models fail to satisfy the phenomenological demand of relativistic outflow at low [r < (0.1 – 0.01)RL ] altitude. In addition, they require either non-monotonic flow velocities and potentials, or (more likely) spatially trapped charges with non-monotonic potentials through which the current carrying charges flow. In both cases, the flow is subject to instabilities of the trapped particle variety, whose associated anomalous resistivity is more than sufficient to restore the voltage drop to relativistic values, making the slow flow solutions physically unrealizable.

5 For pulsars with short periods, such as the Crab, the effects are about comparable.