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\IBVShead{4178}{28 March 1995}

\title{CCD PHOTOMETRY OF SIX FAINT CATACLYSMIC VARIABLES}

\begintext


Photometric observations of several CV candidates were obtained using the
CCD camera on the Danish 1.5m telescope at the European Southern 
Observatory in June/July 1988 (Table 1). Differential instrumental magnitudes
were then derived relative to nearby comparison stars on the same CCD
image. The major goals were to confirm or reject the CV nature of the
targets and to search for orbital variability and eclipses. Detailed analysis
of interesting systems is published separately. This notice presents results
for six objects.
\vskip 2mm
          PG\,1403$-$111

 This object was classified as a CV showing a composite spectrum (Green
et al., 1986). Recent spectrophotometric observations (Zwitter and Munari,
1994) revealed no emission lines or hot continuum. It may be that this
object is a misidentification as a CV because the photometry also showed no
evidence of any variability.
\vskip 2mm
          PG\,1522+122
          
This object was also classified as a CV by Green et al. (1986). The 
photometry showed no indication of a typical CV light curve. There was only a
small decline in brightness of about 0.04 mag within  three  hours.  The
small scatter of about 0.02 mag rules out flickering activity. The object is
probably not a CV.
\vskip 2mm
          NSV\,09208
          
Eggen (1969) lists this object (BPM 24960) as a probable variable white
dwarf suspect. A possible CV nature is assigned in the NSV catalogue. The
1.5-hour light curve shows a slight increase in brightness by about 0.15
mag with superimposed flickering of about 0.1 mag. There is no indication
for a periodic modulation. Nevertheless, the object is likely to be a CV.
\vskip 2mm
          NSV\,14152
          
Haro and Luyten (1960) suggest this blue object (Var 7) to be an eruptive
variable. It is listed as a possible CV in the NSV catalogue. The 0.8-and
4-hour runs show typical flickering activity with an amplitude of about
0.2 mag. Whereas during the first night the system remained nearly constant  
it brightened during the second steadily by about 0.25 mag. The mean
magnitudes on the two nights differ by about 0.35 mag. A periodic 
variation longer than 4 hours is therefore expected.
\vskip 2mm
          CF Gru (2138-453)
         
 Hawkins and Veron (1987) detected the variability of this blue object and
classified it spectroscopically as a CV. CCD photometry by Howell et al.
(1991) revealed hot-spot modulations with a period of 93$\pm$11 min and the
presence of large flickering. The present data set shows generally the
same behaviour, but can be better fitted with a period of 100$\pm$11 min 
(Figure 1).
\vfill \eject

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\centerline{\epsffile{4178-f1.ps}}
\begin{center}
 Figure 1: Differential light curve of CF Gru in integral light. The 
measurements taken on 1988 June 28 are folded with a period of 100 min
(phase arbitrary). This period represents the  present  observation better 
than the 93 min given by Howell et al. (1991).
\end{center}
\epsfysize=10cm
\centerline{\epsffile{4178-f2.ps}}
\begin{center}
 Figure 2: Differential photometry of Hawkins V6 obtained in integral light 
on 1988 July 01. A repeatable modulation with a period of 80 min is present. 
At 6:30 UT the integration time of 60 s was changed to 120 s.
\end{center}
\vfill \eject

\centerline{3}

\vskip 1mm
\begin{center}
Table 1: Observing log. Start is the time for the midpoint of the first 
exposure. The observation interval also includes gaps due to any interruption 
of the exposure series. Magnitudes are in B except for
the NSV objects where the values from  the  NSV  catalogue  are
given. Observations were performed  in  integral  light  except for
NSV\,09208 where a Johnson B filter was used.
\end{center}
\vskip 1mm
\begin{center}
\begin{tabular}{lcccccc}
\hline
   Object& Date & Start & Interval& Int. Time  & Frames &  Mag\\
         & (1988)& (UT) &  (h)    & (s)        &        & \\           
\hline 
\\
            PG\,1403$-$111&  Jun 29 & 01:27:59 & 2.05 &  45  & 94& 16.0\\
            PG\,1522+122&  Jul  01& 00:21:36 & 3.00 & 120  & 73& 16.1\\
            NSV\,09208  &  Jun 30 & 03:48:23 & 1.56 & 180  & 28& 15.8\\
            NSV\,14152  &  Jun 29 & 10:02:04 & 0.84 & 120  & 21& 20.2\\
                      &  Jun 30 & 06:39:19 & 4.06 & 120  & 96& \\
            CF Gru    &  Jun 28 & 07:42:06 & 3.08 & 180  & 53&20.4\\
           Hawkins V6 &  Jul 01 & 05:17:48 & 3.47 &60/120& 98& 18:5\\
\hline
\end{tabular}
\end{center}

\vskip 2mm                                          

          Hawkins V6
          
Based on its outburst behaviour Hawkins (1981, 1983) classified this object
as a CV. The 3.5-hour photometric run shows evidence for a periodic
modulation masked by strong flickering activity (Figure 2). A periodogram 
analysis yielded a possible period of 80 7 min. Further, the light curve shows
a steady decrease of about 0.4 mag over the entire run thus indicating
that the system was probably observed during a decline from outburst.
\vskip 1cm
\beginauthors
\authorsrightcol
R. HAEFNER
Universit\"ats-Sternwarte
Scheinerstr. 1
81679 M\"unchen
Germany
\endauthors


 \references
        
 Eggen, O.J.: 1969, {\it ApJ}, {\bf 157}, 287
         
 Green, R.F., Schmidt, M., Liebert, J.: 1986, {\it ApJS}, {\bf 61}, 305
         
 Haro, G., Luyten, W.J.: 1960, {\it TTB},  No.\,19, 17
         
 Hawkins, M.R.S.: 1981, {\it Nature}, {\bf 293}, 116
 
 Hawkins, M.R.S.: 1983, {\it Nature}, {\bf 301}, 688
         
 Hawkins, M.R.S., Veron, P.: 1987, {\it A\&A}, {\bf 182}, 271
         
 Howell, S.B., Szkody, P., Kreidl, T.J., Dobrzycka, D.: 1991, {\it PASP}, {\bf 103}, 300
          
Zwitter, T., Munari, U.: 1994, {\it A\&AS}, {\bf 107}, 503

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