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Rotational velocities of the giants in symbiotic stars: II. Are S-type symbiotics synchronized?

R. K. Zamanov·M. F. Bode·C. H. F. Melo·R. Bachev·A. Gomboc·I. K. Stateva·J. M. Porter·J. Pritchard
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Abstract

We have measured the projected rotational velocities (v sin i) of the mass donors for 29 S-type symbiotic stars using high resolution spectroscopic observations and the cross-correlation function (CCF) method. The results of the CCF have been controlled with synthetic spectra. The typical rotational velocity of the K and M giants in S-type symbiotics appeared to be 4.5 < vsini < 11.7 km/s. In a sub-sample of 16 S--type symbiotic stars (with known orbital periods and well measured vsini) 15 have deviations from synchronization less then the 3-sigma level. This means that we did not find evidence for a statistically significant deviation from the synchronization for any of these 15 objects. The deviation from synchronization is statistically significant (at confidence level >99%) only for the recurrent nova RS Oph. For 22 S-type symbiotics we give clues as to what their orbital periods could be.

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R. K. Zamanov, M. F. Bode, C. H. F. Melo, R. Bachev, A. Gomboc, I. K. Stateva, J. M. Porter, J. Pritchard. 2007-06-29. Rotational velocities of the giants in symbiotic stars: II. Are S-type symbiotics synchronized?. https://doi.org/10.1111/j.1365-2966.2007.12150.x

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