COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                    Number 1835

                                  Konkoly Observatory,
                                  Budapest
                                  1980 September 1

                                  HU ISSN 0374-0676


SPECTROSCOPY OF THE NOVA-LIKE OBJECT KUWANO (NOVA VULPECULAE
              1979) IN THE YEAR 1979




    Kuwano (1979) discovered on April 5.8, 1979 sudden increase
of brightness of the star in the position (see Ishida et al.
1979):
    alpha_1950.0=20h19m01.08s; delta_1950.0=+21d24'43.1".
The photometric history of the object was reconstructed by Liller and
Liller (1979). They showed that the star varied irregularly between
B=14.5 and 16.6 prior to 1977 and some mini-eruptions were observed 
within the past 80 years. The present outburst began in
late 1977 and within a year the star has reached B=10. After the
discovery in April, 1979 the star fluctuated for several months
on the level of B=9.5. According to Belyakina et al. (1980) the
object dropped to B=13.0 at the end of June 1980.
    The spectrum prior to the outburst was seen on some objectiveprism 
photographs and it was classified as mid-M (Stephenson,
1979). Ishida et al. (1979) found the spectrum around the discovery 
time being of the type A4. According to Mochnacki (1979)
the emissions were seen in H_alpha and H_beta lines. P Cygni profile of
H_alpha displayed the absorption component shifted for 50 km/s towards
the blue. Sharp absorption Balmer lines up to H_11 were detected
by Schmidt and Green (1979). At the end of June 1980 the spectrum
was a mid-M or advanced M-type with H_alpha and Na D emissions (Belyakina 
et a1.,1980).
    Our observational material consists of 7 spectrograms
taken with the 350 mm camera of the coude spectrograph of the
2 m telescope at the Ondrejov Observatory, with the reciprocal
dispersion of 1.7nm mm^{-1} in the blue region (380-497 nm).Kodak
IIa0  emulsions were used throughout. Depending on the photographic

density of the plates (some spectrograms were rather underexposed) 
we have found on the plates strong sharp absorption lines
H_beta to H_8, Ca II lines H and K (stellar), and furthermore fainter
lines of Al I, A1 II, Ca I, Ca II, Cr I, Cr II, Fe I, Fe II,
Mg II, Mn I, Mn II, Ni II, Si II, Sr II, Ti I, Ti II, V II,
Y II (?) and Zr II. Altogether up to 300 lines were detected.
    From the relative intensities of the lines of Ca I (423 nm),
Ti II (431 nm) and H_gamma we have derived the spectral type of the
star F 5 (+-0.1). This is in agreement with the spectral type
as determined from the UBV photometry. Neglecting the interstellar 
reddening the B-V index is close to 0.4 and this corresponds
to the spectral class F 5 (see Allen, 1973).
    Radial velocities of almost all identified lines were measured 
on the Abbe comparator. On four well-exposed spectrograms
between JD. 2444118-2444157 (Nos. 3365,3368,3372 and 3420) the
distribution of individually determined radial velocities was
investigated. The distribution is clearly non-Gaussian, with
pronounced asymmetry towards the negative velocities. We believe
that we can distinguish two sources of the spectra of the object.
Most lines belong to the spectrum of the stationary envelope connected 
with the M star. Assuming the Gaussian distribution, its
average radial velocity is close to (+30+-6)km s^{-1}. The rest of
the lines is produced in an expanding envelope; their velocities
are distributed in the interval from -40 to +25 km s^{-1}. The distribution 
of these velocities displays the maximum at +8 km s^{-1}.
The existence of the expanding envelope is corroborated by the
P-Cygni profile of the H_alpha line.
    It is apparent that there is much hesitation how to classify 
the star in the framework of stellar variability. The proposal 
that we observe the case of a slow nova is clearly inadequate. 
Thus the term nova-like was preferred by the discoverer.
The existence of the late-type spectrum before the outburst suggests 
that the object is related to symbiotic stars. This was
proposed by Bensammar et al. (1980). Future behaviour of the
star should be followed up with vigilance:


LADISAV HRIC and DRAHOMIR CHOCOL                     JIRI GRYGAR
Astronomical Institute of the Slovak              Astronomical Institute o the
Academy of Sciences,059 60 Tatranska               Czechoslovak Academy of Sciences
Lomnica,Skalnate Pleso Observatory                251 65 Ondrejov Observatory      
Czechoslovakia                                    Czechoslovakia

References:
Allen, C.W. 1973, Astrophysical Quantities; Athlone Press,
    London, P.206 [BIBCODE 1973asqu.book.....A ]
Belyakina, T.S., Chuvaev, K.K., Gershberg, R.E., Petrov, P.P.
     1980, IAU Circ. No.3494 [BIBCODE 1980IAUC.3494....3B ]
Bensammar, S., Friedjung,M., Assus, P. 1980, Astron.Astrophys.
     83, 261 [BIBCODE 1980A&A....83..261B ]
Ishida, K., Yamashita, Y., Nariai, K. 1979, IAU Circ. No. 3350 [BIBCODE 1979IAUC.3350....1M ]
Kuwano, Y. 1979, IAU Circ. No. 3344 [BIBCODE 1979IAUC.3344....1K ]
Liller, M.H., Liller, W. 1979, Astron. J. 84, 1357 [BIBCODE 1979AJ.....84.1357L ]
Mochnacki, S. 1979, IAU Circ. No. 3350 [BIBCODE 1979IAUC.3350....1M ]
Schmidt, M., Green, R. 1979, IAU Circ. No. 3350 [BIBCODE 1979IAUC.3350....1M ]
Stephenson, C.B. 1979, IAU Circ. No. 3356 [BIBCODE 1979IAUC.3356....2S ]