Advertisement

Linear and circular polarization for masers with weak zeeman splittings

  • Gerald E. Nedoluha
  • William D. Watson
2. Theory
Part of the Lecture Notes in Physics book series (LNP, volume 412)

Abstract

Theory is reviewed for the linear and circular polarization of radiation from astrophysical masers in which the Zeeman splitting gμ is much less than the spectral linewidth Δω. When gμ > Γ (the decay rate for the molecular states), polarization — mainly linear — can be generated. New results are presented that describe the generation of circular polarization by intensity dependent (or “false”) Zeeman effects. As a result, the magnetic field strengths inferred from the circular polarization of circumstellar SiO masers may be smaller than previous estimates by a factor of 100 or more.

Keywords

Star Formation Linear Polarization Circular Polarization Molecular State Fractional Polarization 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Barvainis, R. E., McIntosh, G. C. & Predmore, C. R. 1987, Nature, 329, 613Google Scholar
  2. Deguchi, S. & Watson, W. D. 1986, ApJ, 300, L15Google Scholar
  3. Deguchi, S. & Watson, W. D. 1990, ApJ, 354, 649Google Scholar
  4. Deguchi, S., Watson, W. D., & Western, L. R. 1986, ApJ, 302, 108Google Scholar
  5. Elitzur, M. 1991, ApJ, 370, 407Google Scholar
  6. Elitzur, M. 1992, Astronomical Masers (Dordrecht: Kluwer), 184Google Scholar
  7. Fiebig, D. & Güsten, R. 1989 A&A, 214, 333Google Scholar
  8. Goldreich, R., Keeley, D. A., & Kwan, J. Y. 1973, ApJ, 182, 55 [GKK]Google Scholar
  9. McIntosh, G. C. & Predmore, C. R. 1991, in Proc. Third Haystack Obs. Conf. (ASP Vol. 16), ed. A. D. Haschick & P. T. Ho, 83Google Scholar
  10. Nedoluha, G. E. & Watson, W. D. 1990a, ApJ, 354, 660Google Scholar
  11. Nedoluha, G. E. & Watson, W. D. 1990b, ApJ, 361, L53Google Scholar
  12. Nedoluha, G. E. & Watson, W. D. 1990c, ApJ, 361, 653Google Scholar
  13. Nedoluha, G. E. & Watson, W. D. 1991, ApJ, 367, L63Google Scholar
  14. Nedoluha, G. E. & Watson, W. D. 1992a, ApJ, 384, 185Google Scholar
  15. Nedoluha, G. E. & Watson, W. D. 1992 b, ApJ, in preparationGoogle Scholar
  16. Western, L. R. & Watson, W. D. 1983a, ApJ, 274, 195Google Scholar
  17. Western, L. R. & Watson, W. D. 1983b, ApJ, 275, 195Google Scholar
  18. Western, L. R. & Watson, W. D. 1984, ApJ, 285, 158Google Scholar
  19. Zhao, J-H., Goss, W. M., & Diamond, P. 1992, preprint]Google Scholar

Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Gerald E. Nedoluha
    • 1
  • William D. Watson
    • 2
  1. 1.Naval Research LabNRC Cooperative Research AssociateWashington DCUSA
  2. 2.Loomis Lab of PhysicsUniversity of IllinoisUrbanaUSA

Personalised recommendations