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\begin{document}
\IBVShead{4275}{5 December 1995}

\title{PHOTOMETRIC OBSERVATIONS OF NSV\,13368}

\begintext

The variability of NSV\,13368 was initially announced by Thorndike (1942).
According to the New Catalogue of Suspected Variable Stars (Kholopov, 1982),
NSV\,13368 (HV\,10648, CSV\,005292) is an RR Lyrae variable star with a 
photographic magnitude variation range between 13.4 and 14.3. NSV\,13368
can unambiguously be identified with star GSC\,0524.0645.

From August 3 to October 29, 1995, the star was observed on 18 nights 
in the V band,  using a Starlight Xpress CCD camera attached to the Newtonian
focus of the 0.41-m telescope at Observatorio de Mollet (Spain).
GSC\,0524.0669 was used as comparison star, and GSC\,0524.0839 and
GSC\,0525.1384 as check stars (see Figure 1).

These observations show that NSV\,13368 is in fact an RR Lyrae star with an
asymmetric light curve ((M$-$m)/P=0.12), an amplitude in the V band of 0.8
magnitudes, and a period close to 13 hours and 36 minutes (Figure 2).
We derived the following ephemeris:
\vskip 3mm
\centerline{Max. = HJD\,2449957.418  +  0.56684 $\times$ E}
\hspace*{7.1cm}$\pm$0.005\ \ $\pm$0.00015
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\centerline{\epsffile{4275-f1.ps}}
\centerline{Figure 1. C = Comparison star, Ck$_1$ and Ck$_2$ = Check stars.}
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\centerline{2}
\epsfysize=7cm
\centerline{\epsffile{4275-f2.ps}}
\centerline{Figure 2. Light curve of NSV\,13368 in the V band.}
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\beginauthors
\authorsrightcol
Josep M. GOMEZ-FORRELLAD
Enrique GARCIA-MELENDO
Grup d'Estudis Astronomics
Apartado 9481
08080 Barcelona
Spain
e-mail: jmgomez@astro.gea.cesca.es
\endauthors


\references

Kholopov, P. N., editor, 1982, New Catalogue of Suspected Variable Stars,
Moscow

Thorndike, S. L., 1942, {\it Bulletin of the Harvard College Observatory}, No.\,916
\end{document}

