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\IBVShead{4446}{3 March 1997}

\title{Variable stars in the Globular Cluster NGC\,6717}

\begintext

    NGC\,6717 ($C1852-2246, l = 12\fdg 88, b =-10\fdg 90$)
according to its spectral class F8 (Hesser \& Shawl, 1985)
is a  relatively high metallicity but poorly studied cluster.
Goranskii (1979) obtained an upper  part of the CMD and detected one RR Lyrae 
variable near the cluster center. At present the only CCD
photometric study of this cluster was made by Brocato et al. (1996).
Our search for RR Lyrae variables was made on the base of these CCD
observations by the method described in Kadla et al. (1996).

The cluster has a small apparent angular radius  $r = 1\farcm9$ 
(Kukarkin, 1974) and a high central concentration. For this reason the 
CMD was obtained for stars with  $13'' < r < 120''$ (Figure 1). In the instability strip there are two stars:
one is a known RR Lyr variable (V1) detected by Goranskii (1979) and the other is a
suspected RR Lyr star. Their positions are shown in the cluster chart (Figure 2).
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Figure 1.
The color -- magnitude diagram for the globular cluster NGC\,6717.
The known RR Lyrae star is denoted by $\circ$ , suspected -- $\bullet$
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Figure 2. Chart of the cluster. Variable stars are denoted by $\bigcirc$
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We are grateful to the Russian Foundation for Basic Research for financial
support.
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\beginauthors  
\authorsrightcol
A.N. GERASHCHENKO
Z.I. KADLA
YU.N. MALAKHOVA
Central Astronomical Observatory of 
the Russian Academy of Sciences at 
Pulkovo, 196140 Saint--Petersburg, 
Russia, e-mail: mal@pulkovo.spb.su
\endauthors

\references

Brocato, E., Buonanno, R., Malakhova, Yu. \& Piersimoni, A.M.,
 1996, {\it A\&A}, {\bf 312}, 80

Goranskii, V.P., 1979, {\it Soviet Astronomy}, {\bf 23}, 284

Hesser, J.E \& Shawl, S.J., 1985, {\it PASP}, {\bf 97}, 465

Kadla, Z.I., Gerashchenko, A.N. \& Malakhova, Yu.N., 1997, {\it IBVS},
No.\,4413 

Kukarkin, B.V., 1974, The General Catalogue of Globular Clusters
 of our Galaxies. Publishing House Nauka, Moscow

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