COMMISSION 27 OF THE I.A.U.
                INFORMATION BULLETIN ON VARIABLE STARS
                            Number 3261

                                                    Konkoly Observatory
                                                    Budapest
                                                    10 November 1988

                                                    HU ISSN 0374 - 0676


              ON THE PRIMARY MASS OF NSV 12615 *

The cataclysmic variable NSV 12615 shows eclipses repeating with a
period of 0.06142 d (Jablonski and Steiner, 19871. In a recent
paper Mukai et al. (1988) presented spectroscopic observations
around H_alpha and reported on discrepancies in estimating the
primary mass. As these authors suggest, one possibility to abolish
this problem would be to enhance the semi-amplitude of the orbital
velocity from 56 km/s to ~100 km/s corresponding to a primary mass
of=~0.2 M_sun.
   About three months after their observations a spectrum of that
object was obtained using the ESO 3.6m telescope equipped with the
Boller & Chivens spectrograph and CCD. Besides H_alpha the HeI line
lambda 5876 is present in the recorded wavelength region (Fig .1).
Spectral resolution and integration time were nearly identical
with their spectroscopy (binned data) and similar values for the
FWZI of H_alpha and the separation of the components can be derived.
Given their epoch of the inferior conjunction of the secondary and
the known period the corresponding phase for that spectrum is
0.8+/-0.3, i.e. near the maximum of the radial velocity curve. A
Gauss fit to the line wings of H_alpha yields a (heliocentric)
velocity of ~60+/-10 km/s. This either would correspond to a higher
semi-amplitude of = 120 km/s or to a shift of the gamma-velocity by
= 60 km/s. The higher semi-amplitude would still (or even better)
be in accordance with their diagnostic diagram and would thus
favour a low primary mass.


                         [FIGURE 1]

            Figure 1   Spectrum of NSV 12615


* based on observations collected at the European Southern
   Observatory La Silla/Chile


                        R. HAEFNER

                   Universitats-Sternwarte
                      Scheinerstr. 1
                     D-8000 Munchen 80
                   Fed. Rep. of Germany



References:

Jablonski. F.J., Steiner, J.E.: Astrophys. J. 313, 376, 1987 [BIBCODE 1987ApJ...313..376J ]
Mukai, K., Corbet, R.H.D., Smale, A.P.: Mon. Not. R. astr. Soc. 234, 291, 1988 [BIBCODE 1988MNRAS.234..291M ]