COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                    Number 2089

                                Konkoly Observatory
                                Budapest
                                1982 February 17

                                HU ISSN 0374-0676





              1981 UBVR PHOTOMETRY OF UV Psc



   As part of an on-going program of UBVR photometry of RS CVn binaries, we
have observed the short-period system UV Psc (BD +6d189) in October and November
of 1981. The observations were made with the University of New Mexico's 61-cm
Capilla Peak Observatory telescope. A photon-counting system using a cooled
(-20d C) EMR 641A phototube was employed. The star BD +6d185 (SAO 108761) was
used as the comparison star.
   The results of these observations are shown in Figure 1-4. Magnitudes are
given in the instrumental UBVR system. The data has been folded so that both
primary and secondary minima are clearly visible and the presence of any 
distortion wave more easily detected. The statistical error of any single point is on
the order of +-0.01 magnitude. The phases were calculated using HJD=2443463.3493
+ 0.861046 E (Oliver, 1974; IBVS #1415). Table I gives a phase log of the
observations.
   Few observations of UV Psc have been published to date. Oliver (1974) 
observed UV Psc photometrically and found that the light curve of UV Psc did not
have any large asymmetries. Also, Oliver presented a light curve made by Carr
in 1968. The similarities between the light curves of Oliver and Carr indicated
that UV Psc had a rather consistent light curve. Previous observations we made
in 1979 and 1980 (Zeilik et al., 1981; IBVS #2006) did not show any evidence for
an asymmetrical distortion wave, but did indicate that the system undergoes 
radical changes in its light curve.


                           [FIGURE 1]
                           [FIGURE 2]
                           [FIGURE 3]
                           [FIGURE 4]


  Our present light curves are much improved over those obtained in 1979 and
1980. The span of observations was on a much shorter time scale and phase coverage
more complete. These observations do indicate the presence of an asymmetrical 
distortion wave with a maximum amplitude near 0.3 phase. A large asymmetry in the
secondary eclipse is also evident. The system still appears to be quite active
as noted by a large depression going into the primary minimum on 11/13/81, especially 
evident at U and V. Depths of the secondary minima relative to the primary
remain consistent with those of the 1980 observations with the secondary depth
increasing at longer wavelengths relative to the primary.


 TABLE I - 1981 Phase Log of UV Psc
-----------------------------------
Date (UT)       Phase
-----------------------------------
10/18       0.62 --> 0.72
10/20       0.83 --> 0.06
10/24       0.58 --> 0.64
10/26       0.73 --> 0.83
11/3        0.04 --> 0.25
11/5        0.25 --> 0.58
11/13       0.74 --> 0.87
-----------------------------------



       M. ZEILIK, R. ELSTON, G. HENSON, P. SCHMOLKE, P. SMITH

                  Capilla Peak Observatory
             Department of Physics and Astronomy
                  University of New Mexico
                   Albuquerque, NM 87131
                           U.S.A.




References:
Oliver, J. P., 1974, Ph.D. Thesis, University of California, Los Angeles,
   California, U.S.A. [BIBCODE 1974PhDT.........1O ]
Zeilik M., Elston R., Henson G., Schmolke P., Smith P., 1981, IBVS # 2006.