\documentstyle[epsf]{article}
\input ibvs.sty

\begin{document}
\IBVShead{4344}{20 May 1996}
\title{New variable stars in the 66 Ophiuchi field}
\begintext

This paper continues the series of studies dealing with the search
of new variables based on Moscow collection of plates.
Nine new variables were discovered in the field $10\degr\times10\degr$
centered on 66 Oph (Var 25--33).

The variables were estimated on plates taken on JD\,2442812--2448092.
The data on the new variable stars are presented in Tables 1--3.
Finding charts and phased light curves are shown in Figures 1 and 2.
The standard sequence near NGC\,6426 was used to obtain the magnitudes of
comparison stars (Shugarov, unpublished).

\medskip
\centerline {Remarks on individual stars}

\medskip
Var 25. Not present or very faint on the Palomar blue print. The star
was seen on 14 plates. Three outbursts were observed.
Their duration  is more than 6 but less than 28 days (Figure 3).
Outbursts (JD\,24...):

\begin{center}
\medskip
\begin{tabular}{cccccccc}
1& 42957.338& 15.40& 42957.499& 15.14& 2& 44131.297& 15.68\\
 & 42957.370& 15.35& 42961.323& 15.35&  &          &      \\
 & 42957.403& 15.35& 42961.499& 15.46& 3& 48090.305& 14.93\\
 & 42957.437& 15.40& 42963.332& 15.63&  & 48091.305& 15.29\\
 & 42957.469& 15.14& 42963.505& 15.57&  & 48092.427& 15.32\\
\end{tabular}
\end{center}

\medskip

Var 30. Periods about 486 and 242 days are possible (Figure 2 for Var 30).
Epoch JD\,2443282. Red on Palomar prints.
The star is a strong enough IRAS source.

Var 31. Double. Very close, non-coloured southwestern component
is present on Palomar prints, but the image on our plates
is single. It is possible that the neighbouring star was
estimated in minima.

Var 32. RRb type.

Var 33. The cycle of variability is about $70-80^d$. Minimum
brightness varies (Figure~4).

\begin{center}
\medskip

Table 1. Coordinates and Identifications of Variable Stars
\vskip 1mm
\begin{tabular}{lcccc}
\hline
\noalign{\medskip}
Var & $\alpha(2000.0)$ & $\delta(2000.0)$ & GSC\ \ \ & IRAS\\
\noalign{\medskip}
\hline
\noalign{\medskip}
Var 25&   18\fh 04\fmm 17\fss3&    4\degr43\farcmm 44\farcss&       &        \\
Var 26&   18 12 30.1&     8 36 35&      1009.1098&      18101+0835\\
Var 27&   18 13 26.6&     8 52 28&      1009.0361&      18110+0851\\
Var 28&   18 04 15.0&     6 04 13&               &                \\
Var 29&   17 50 56.0&     7 18 27&               &                \\
Var 30&   18 07 07.9&     8 22 46&      1008.1326&      18047+0822\\
Var 31&   18 02 16.6&     8 56 56&      1008.0492&                \\
Var 32&   18 04 34.4&     8 19 49&               &                \\
Var 33&   18 05 25.1&     8 15 09&      1008.1491&                \\
\noalign{\medskip}
\hline
\end{tabular}
\end{center}
\vfill \eject

\centerline{2}
\begin{center}
Table 2. Data on New Variable Stars
\vskip 1mm
\begin{tabular}{lccccclc}
\hline
\noalign{\medskip}
Var & $N$ & Type & Max& Min& $M-m$ & Max, JD & Period\\
\hline
\noalign{\medskip}
Var 25&   234&    UG   &   15.00& $<21.0$ &       \\
Var 26&   225&    M    &   13.80& $<17.3$ &     & 2448090.3 &   269\fd 1 \\
Var 27&   229&    SRa  &   13.40&  15.60  & 0.35& 2445203.3 &   156.8      \\
Var 28&   228&    RRab &   14.90&  16.50  & 0.12& 2443726.32&     0.438655 \\
Var 29&   223&    RRab &   15.20&  17.10  & 0.12& 2442951.35&     0.438333 \\
Var 30&   231&    SRa  &   14.30&  16.50  &       \\
Var 31&   233&    M    &   13.30&  16.10: &     & 2443987.5 &   200.0      \\
Var 32&   229&    RRab &   14.00&  15.00  & 0.30& 2444397.41&     0.638544 \\
Var 33&   234&    SRb  &   13.90&  16.50  &       \\
\hline
\end{tabular}
\end{center}

\epsfysize=15cm
\centerline{\epsffile{4344-f1.ps}}
\centerline{Figure 1. Finding charts}
\vfill \eject

\centerline{3}
\epsfysize=20cm
\centerline{\epsffile{4344-f2.ps}}
\centerline{Figure 2. Light curves}
\vfill \eject

\centerline{4}
\epsfysize=6cm
\centerline{\epsffile{4344-f3.ps}}
\centerline{Figure 3. Light curve of Var. No.\,25}
\vskip 5mm
\epsfysize=6cm
\centerline{\epsffile{4344-f4.ps}}
\centerline{Figure 4. Light curve of Var. No.\,33}


\vskip 3mm
\begin{center}
Table 3. Comparison Stars
\vskip 1mm
\begin{tabular}{lccccccc}
\hline
\noalign{\medskip}
Var & a & b & c & d & e & f & g \\
\hline
\noalign{\medskip}
Var 25&  14.82&  15.18&  15.74&  16.65&  17.50&  17.82\\
Var 26&  13.71&  13.84&  14.45&  15.26&  15.83&  16.54&  17.33\\
Var 27&  12.82&  13.38&  13.66&  14.14&  14.38&  14.93&  15.55\\
Var 28&  14.88&  14.98&  15.16&  15.44&  15.90&  16.46\\
Var 29&  15.05&  15.45&  15.72&  15.98&  16.90&  17.50\\
Var 30&  13.80&  14.43&  14.85&  14.94&  16.12&  16.82\\
Var 31&  12.80&  13.46&  13.93&  14.46&  14.86&  15.94&  16.16\\
Var 32&  13.91&  14.34&  15.10\\
Var 33&  13.84&  14.06&  15.08&  15.76&  16.57\\
\hline
\end{tabular}


\end{center}

\vskip 1cm

\beginauthors
\authorsrightcol
S.V. ANTIPIN
Sternberg Astronomical Institute
13, Universitetskij Prosp.,
Moscow 119899, Russia
\endauthors
\end{document}
