COMMISSION 27 OF THE I. A. U.
            INFORMATION BULLETIN ON VARIABLE STARS
                        Number 3015


                                        Konkoly Observatory
                                        Budapest
                                        21 April 1987

                                        HU ISSN 0374-0676


         HQ AND HV ANDROMEDAE: FURTHER PHOTOMETRIC STUDY
                      OF POLAR CANDIDATES

  The variability of these stars was discovered by Meinunger (1975) and they
were classified as rapid irregular variables. Later on, Meinunger (1980)
pointed out that the spectrograms of the stars show the presence of weak emission
lines of H-alpha and H-beta and therefore he classified them as cataclysmic 
variables possibly belonging to polars. However, no other spectroscopic or 
polarimetric observations were made since that time. Here we discuss the results
of the photometric investigation of stars on astrographic plates of Sonneberg
Observatory. The brightness of Meinunger's (1975) comparison stars was used.

  HQ And (=S 10774). After 800d - rise of brightness at the beginning of our
observations, the luminosity changes become larger (in amplitude). However,
this effect might be partially explained by the decrease of the exposure time.
It seems to be real as some specially obtained plates show rapid variability
with the characteristic time of about one-two hours. Unfortunately, these data
are insufficient to discuss the possible orbital period.
  The brightness difference between "active" and "inactive" states is smaller
as compared to 3 magn. in AM Herculis (Hudec and Meinunger 1976), and one may
show only one sure "inactive" state near JD 2440800, and two possible ones near
2441900 and 2446100. The upper limit for the duration of the last mentioned
minimum is about 600d, but between the two first ones is about 1100 d.

 HV And (=S 10777) has much more prominent "eclipse-like" "excursions" to
"inactive state", which are more similar to that of MV Lyrae before switching
off of the accretion in the system (Andronov and Shugarov 1982, Wenzel and
Fuhrmann 1983), than to polars. However, the long-period polar QQ Vulpeculae
underwent such "excursions", during which the brightness decreases by ~2.5
magn, but in this system their duration is of about two weaks (Andronov et
al., 1987), that is much shorter, than in HV Andromedae (upper limit 300d).


                               [FIGURE 1]


Andronov and Banny (1985) argued for 80.6-min photometric period of the
star derived from four nights of observations. However this value might be
corrected by future observations, our present data are not sufficient to
study the orbital variability.
  The present data are in agreement with the classification of Meinunger
(1980), who supposed these stars were candidates for polars. But naturally,
the classification of these stars is not fully confirmed, so the theoretical
models for luminosity changes in polars (eg. Andronov 1986 and refs therein)
might not yet be applied to these two stars.
  The light curves have very large gaps, and it would be important to fill
them by using other plate collections, especially at Harvard and Bamberg. Only
complex investigations may enable us to understand these interesting objects.



                            I.L. ANDRONOV

                     Department of Astronomy, Faculty of Physics
                     Odessa State University,
                     T.G. Shevchenko Park, Odessa 270014 USSR

                     Universitats-Sternwarte, Friedrich-Schiller
                     Universitat Jena, Schillergasschen 2,
                     Jena 6900 GDR


                           L. MEINUNGER

                     Sternwarte Sonneberg, Zentralinstitut fur
                     Astrophysik der AdW der DDR
                     Sonneberg 6400 GDR





 References:

 Andronov, I.L., 1986, in: "Eruptive Phenomena in Stars" (ed. L. Szabados)
       Commun. Konkoly Obs. Hung. Acad. Sci. No. 86, 371. [BIBCODE 1986CoKon..86..371A ]
						[CoKon No. 86]
 Andronov, I.L. Banny, M.I., 1985, Inform. Bull. Var. Stars No. 2763.
 Andronov, I.L., Kundashkina, L.S., Yavorskij, Yu.B., 1987, in: "Problemy
       astronomii" 2, Preprint UkrNIINTI No. 430-Uk87, 162.
 Andronov, I.L., Shugarov, S.Yu., 1982, Astron. Tsirk. No. 1218, 3. [BIBCODE 1982ATsir1218....3A ]
 Hudec, R., Meinunger, L., 1976, Inform. Bull. Var. Stars No. 1184.
 Meinunger, L., 1975, Mitt. Veranderl. Sterne 7, 1. [BIBCODE 1975MitVS...7....1M ]
      1980, Inform. Bull. Var. Stars No. 1795.
 Wenzel, W., Fuhrmann, B., 1983, Mitt. Veranderl. Sterne 9, 175. [BIBCODE 1983MitVS...9..175W ]