Rotational velocities of the giants in symbiotic stars : II . Are they synchronized ? ⋆
نویسندگان
چکیده
We have measured the rotational velocities (v sin i) of the mass donors for 36 symbiotic stars using the cross-correlation function (CCF) method. We got a meaningful CCF for 29 objects and we derived only upper limits for 7 objects (v sin i< 3.5 km s, 6 out of these 7 are symbiotic Miras). In a sub-sample of 16 S–type symbiotic stars (with known orbital periods and well measured v sin i) 15 have deviations from synchronization less then the 3-σ 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. Our upper limits for symbiotic Miras do not contradict the suggestion of orbital synchronization. For 23 S-type symbiotics we give clues as to what their orbital periods could be.
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