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Polarization properties of R Cas SiO masers

Published online by Cambridge University Press:  24 July 2012

K. A. Assaf ,
P. J. Diamond ,
A. M. S. Richards  and
M. D. Gray
K. A. Assaf
Affiliation:
University of Manchester, Oxford Road, Manchester, M13 9PL, UKemail: kam@jb.man.ac.uk
P. J. Diamond
Affiliation:
CSIRO Astronomy and Space Sciences, PO Box 76, Epping, NSW 1710, Australia email: philip.diamond@csiro.au
A. M. S. Richards
Affiliation:
University of Manchester, Oxford Road, Manchester, M13 9PL, UKemail: kam@jb.man.ac.uk
M. D. Gray
Affiliation:
University of Manchester, Oxford Road, Manchester, M13 9PL, UKemail: kam@jb.man.ac.uk
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Abstract

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Silicon monoxide maser emission has been detected in the circumstellar envelopes of many evolved stars. It is a good tracer of the wind dynamics within a few stellar radii of the central star. We investigated the polarization morphology in the circumstellar envelope of an AGB star, R Cas, by using the VLBA to map the linear and circular polarization of the v=1, J=1-0 SiO maser transition during 23 epochs over two stellar cycles. The average fractional circular polarization is a few percent. The average fractional linear polarization per epoch is 11–58%, but some isolated features exceed 100%, probably because the total intensity emission is smoother and more resolved-out. The maser electric polarization vector angle has a preferrential tendency to be either parallel or perpendicular to the radial direction to the star.

Keywords

masers – polarization – star: AGB – star: late-type star: individual: R Cas.
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 8 , Symposium S287: Cosmic Masers - from OH to H0 , January 2012 , pp. 235 - 239
Copyright
Copyright © International Astronomical Union 2012

References

Assaf, K. A., Diamond, P. J., Richards, A. M. S., & Gray, M. D. 2011, MNRAS, 415, 1083CrossRefGoogle Scholar
Barvainis, Richard, McIntosh, Gordon, & Predmore, C. Read 1987, Nature, 329, 613.CrossRefGoogle Scholar
Desmurs, J. F., Bujarrabal, V., Colomer, F., & Alcolea, J. 2000, A&A, 360, 189.Google Scholar
Elitzur, M.ApJ, 457, 415.CrossRefGoogle Scholar
Elitzur, M.ApJ, 504, 390.CrossRefGoogle Scholar
Garcia-Barreto, J. A., Burke, B. F., Reid, M. J., Moran, J. M., Haschick, A. D. & Schilizzi, R. T. 1988, ApJ, 326, 954.CrossRefGoogle Scholar
Goldreich, P., Keeley, D. A., & Kwan, J. Y. 1973, ApJ, 179, 111.CrossRefGoogle Scholar
Gonidakis, I., Diamond, P. J., & Kemball, A. J. 2010, MNRAS, 406, 395.CrossRefGoogle Scholar
Gray, M. D., Wittkowski, M., Scholz, M., Humphreys, E. M. L., Ohnaka, K. & Boboltz, D. 2009, MNRAS, 394, 51.CrossRefGoogle Scholar
Habing, H. J. 1996, A&AR, 7, 97.Google Scholar
Haverkorn, M., Katgert, P. & de Bruyn, A. G. 2003, A&A, 403, 1031.Google Scholar
Haverkorn, M., Katgert, P. & de Bruyn, A. G. 2003, A&A, 404, 233.Google Scholar
Herpin, F., Baudry, A., Thum, C., Morris, D. & Wiesemeyer, H. 2006, A&A, 450, 667.Google Scholar
Kemball, A. J. & Diamond, P. J. 1997, ApJ, 481, L111.CrossRefGoogle Scholar
Kemball, A. J., Diamond, P. J., Gonidakis, I., et al. 2009, ApJ, 698, 1721.CrossRefGoogle Scholar
Kemball, A. J., Diamond, P. J., Richter, L., Gonidakis, I., & Xue, R. 2011, ApJ, 743, 69.CrossRefGoogle Scholar
Reid, Mark J. & Menten, Karl M. 1997 ApJ, 476, 327.CrossRefGoogle Scholar
Troland, T. H., Heiles, C., Johnson, D. R., & Clark, F. O. 1979, ApJ, 232, 143.CrossRefGoogle Scholar
Western, L. R. & Watson, W. D. 1983, ApJ, 275, 195.CrossRefGoogle Scholar
Vlemmings, W. H. T., van Langevelde, H. J., Diamond, P. J., Habing, H. J., & Schilizzi, R. T. 2003, A&A, 407, 213.Google Scholar