COMMISSION 27 OF THE I. A. U.
       INFORMATION BULLETIN ON VARIABLE STARS
                    NUMBER 393

                            Konkoly Observatory
                            Budapest
                            1969 October 17


     A SPECTROSCOPIC STUDY OF THE TRIPLE SYSTEM
                      VV ORIONIS

  The importance of a new spectroscopic study of this
eclipsing system has been pointed out by several authors.
VV Orionis consists of a system of three bodies; but the
orbit of the 3rd body is given, with great reserve, only by
Daniel who lists the approximate values of the elements.
There is also a great uncertainty in the mass ratio of the
two principal bodies ranging from m_2/m_1=0.34 according to
the catalogue by Kopal and Shapley to m_2/m_1=1.0 according
to Struve and Luyten.
  From 26 plates (dispersion 34 A/mm) secured at the
Observatory of Merate we have computed new spectroscopic
elements by means of the programme by Bertiau; we have then
computed the following orbital elements of the long period
variation from all the residuals obtained up to date, 
covering about 200 cycles of the 3rd body:

  K     = 15.75   +/- 4.98   P      = 115.8741 +/- 0.0139
  V_0   = 0.778   +/- 4.00   T_0    = 2419827.129 +/- 9.933
  e     = 0.295              f(m)   = 0.042
  omega = 46.06deg +/- 2.38  a seni = 24.237 x 10^6

After correction for the 3rd body in our velocities,
we have computed the following elements for the two
principal bodies:

K     = 139.92 +/- 8.86    P       = 1.4854 +/- 0.035
V_0   =  26.34 +/- 7.70    T_0     = 2440251.801 +/- 1.285
e     =   0.077+/- 0.74    f(m)    = 0.419 
omega =  84.25 +/- 2.66    a sen i = 2.85 x 10^6


     From the microphotometer tracings we have noticed
that the violet (red) side of the hydrogen lines have faint
extensions when the primary receeds (approaches): this 
effect must be due to the secondary component. We have
measured the relative Doppler shifts of the two components
from the tracings and, within the large uncertainties of
such measures, we have determined K2 about 320 km/sec. This
gives a mass ratio of m2/m1=0.44.
     We have then determined the masses of the three
bodies, without any assumption:

      M_1 = 10.2        M_2 = 4.5      M_3 = 2.3
      

Osservatorio Astronomico di Brera-Milano

                             G. BELTRAMI,     P. GALEOTTI





References:
Bertiau, I. A. U., Symp. n. 30, p. 227 [BIBCODE 1967IAUS...30..227B ]
Daniel, Pub. Allegheny Obs., 3, 179, 1915 [BIBCODE 1916PAllO...3..179D ]
Kopal, and Shapley, Jodrell Bank Ann., 1, 141, 1956
Struve and Luyten, Ap. J., 110, 160, 1949 [BIBCODE 1949ApJ...110..160S ]