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
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.