Basic data (System:1727)

Identifiers:

Orbit

Note

Abstract:
Eta Virginis is a bright (V = 3.89) triple system of composite
spectral type A2IV that has been observed for over a dozen years with
both spectroscopy and speckle interferometry. Analysis of the speckle
observations results in a long period of 13.1 years. This period is
also detected in residuals from the spectroscopic observations of the
71.7919-day short-period orbit. Elements of the long-period orbit
were determined separately using the observations of both techniques.
The more accurate elements from the speckle solution have been assumed
in a simultaneous spectroscopic determination of the short- and
long-period orbital elements.  The magnitude difference of the speckle
components suggests that lines of the third star should be visible in
the spectrum.  In our blue and red spectra only the Mg II line at 4481
angstroms appears to show a third component, however, and it is a very
broad and weak feature.  The equatorial rotational velocities of the
short-period pair are quite low, about 8 km/s each.

Radial velocities used in this orbit

xJD	Rad.Vel.	O-C or error	Weight	Component	Offset	Comment
-2,400,000.0	(km/s)	(km/s)			(km/s)
17710.630	0.1	0	1	a
17714.750	0.7	0	1	a
17716.630	1.2	0	1	a
17739.610	3.6	0	1	a
17989.880	5.0	0	1	a
18021.810	5.8	0	1	a
18031.820	3.7	0	1	a
18052.620	4.6	0	1	a
18077.620	3.3	0	1	a
18087.580	2.6	0	1	a
18089.600	7.3	0	1	a
18103.610	5.4	0	1	a
18355.790	5.7	0	1	a
18642.930	10.0	0	1	a
18706.740	10.0	0	1	a
18727.820	9.9	0	1	a
18736.730	8.2	0	1	a
18753.790	9.0	0	1	a
18757.910	9.6	0	1	a
18759.790	10.6	0	1	a
18764.700	10.2	0	1	a
43670.605	9.5	0	1	a
43671.648	9.2	0	1	a
44040.616	5.5	0	1	a
44178.023	5.3	0	1	a
44356.834	3.6	0	1	a
44357.699	4.4	0	1	a
44738.743	2.3	0	1	a
44739.741	2.4	0	1	a
45074.843	1.1	0	1	a
45075.799	2.6	0	1	a
45076.769	1.5	0	1	a
45078.808	2.2	0	1	a
45723.009	0.7	0	1	a
45784.822	2.2	0	1	a
45814.672	1.0	0	1	a
45855.715	0.7	0	1	a
46534.709	3.6	0	1	a
46583.740	4.0	0	1	a
46586.716	4.2	0	1	a
46866.883	6.0	0	1	a
46867.790	5.6	0	1	a
46868.780	6.2	0	1	a
46970.723	6.8	0	1	a
46971.697	6.1	0	1	a
46972.719	5.3	0	1	a
46974.691	6.5	0	1	a
47151.035	8.2	0	1	a
47152.040	7.9	0	1	a
47153.077	7.3	0	1	a
47244.857	8.5	0	1	a
47245.752	7.9	0	1	a
47246.903	8.9	0	1	a
47247.897	8.4	0	1	a
47248.900	8.4	0	1	a
47308.807	8.3	0	1	a
47309.833	8.4	0	1	a
47310.821	8.4	0	1	a
47312.819	8.4	0	1	a
47313.781	9.3	0	1	a
47555.984	9.5	0	1	a
47556.988	10.7	0	1	a
47623.768	10.5	0	1	a
47625.653	10.0	0	1	a
47626.832	10.5	0	1	a
47916.050	9.5	0	1	a
48004.756	10.1	0	1	a
48007.781	10.3	0	1	a
48056.645	11.0	0	1	a
48057.633	11.0	0	1	a
48345.794	9.4	0	1	a

Plot