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Pulsar Polarization

Published online by Cambridge University Press:  14 August 2015

D. C. Backer*
Affiliation:
Radio Astronomy Laboratory, Berkeley

Extract

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Over ten years ago Radhakrishnan and his coworkers in Australia detected a smooth variation of the electric vector through 90° during the brief pulses from the Vela pulsar. This observation led to the hypothesis that pulsar radiation is beamed along a magnetic pole. While subsequent observations gave ample support to this model, we find that less than half of the pulsars have average profiles which are consistent with the magnetic pole hypothesis. Statistical analyses of individual pulse polarization data now reveal that the average profiles obscure the basic nature of linear polarization in pulsars: two orthogonal modes are typically present, and individually these modes agree with the magnetic pole model. We explain the occurrence of orthogonal modes by a simple geometry for the polarized subpulse beam in relation to the magnetic axis. Theoretical models for subpulse polarization invoke both a combination of emission mechanism effects and propagation effects. We conclude with directions for further research.

Type
III. Radio Observations of Pulsars
Copyright
Copyright © Reidel 1981 

References

Backer, D.C., Rankin, J.M., and Campbell, D.B.: 1975, Astrophys. J. 197, pp. 481487 (APS II).Google Scholar
Backer, D.C., Rankin, J.M., and Campbell, D.B.: 1976, Nature 263, pp. 202207 (APS IV).CrossRefGoogle Scholar
Backer, D.C. and Rankin, J.M.: 1980, Astrophys. J. Suppl. 42, pp. 143173 (APS VI).Google Scholar
Cheng, A.F. and Ruderman, M.A.: 1979, Astrophys. J. 229, pp. 348360.Google Scholar
Cordes, J.M., Rankin, J., and Backer, D.C.: 1978, Astrophys. J. 223, pp. 961973 (APS V).Google Scholar
Drake, F.D. and Craft, H.D. Jr.: 1968, Nature 220, pp. 231235.Google Scholar
Lyne, A.G., Smith, F.G., and Graham, D.A.: 1971, Monthly Notices Roy. Astron. Soc. 153, pp. 337382.Google Scholar
Manchester, R.N.: 1971a, Astrophys. J. Letters 167, pp. L101L105.Google Scholar
Manchester, R.N.: 1971b, Astrophys. J. Suppl. 23, pp. 283322.Google Scholar
Manchester, R.N., Taylor, J.H., and Huguenin, G.R.: 1975, Astrophys. J. 196, pp. 83102.Google Scholar
Melrose, D.B.: 1978, Australia-USSR-USA Symposium on Pulsars and Supernova Remnants, Sydney.Google Scholar
Morris, D., Schwartz, U.J., and Cooke, D.J.: 1970, Astrophys. Letters 5, pp. 181186.Google Scholar
Radhakrishnan, V. and Cooke, D.J.: 1969, Astrophys. Letters 3, pp. 225229.Google Scholar
Ruderman, M.A.: 1976, Astrophys. J. 203, pp. 206208.CrossRefGoogle Scholar