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\begin{document}
\IBVShead{4424}{17 January 1997}

\title{NSV\,00361 IS AN OVERCONTACT BINARY SYSTEM IN PISCES}

\begintext

NSV\,00361 (HV\,06379, CSV\,000111, P\,2493, GSC\,0015.0112) was announced 
as a possible RR Lyrae type star by Shapley and Hughes (1934). According to Kholopov 
(1982) it varies from the 12.4 to 13.0 photographic magnitudes, without 
giving other data about its variability. 

In order to have more information about this star, NSV\,00361 was included in the program of
the Grup d'Estudis Astronomics for the identification and characterization
of new variable stars. The object was observed for 12 nights between 10
October 1996 and 2 December 1996 at Monegrillo Observatory (Spain).  
A CCD camera equipped with B and V filters was used attached to the 0.4-m 
telescope. BD+02\degr 0139 (GSC\,0015.0334) and GSC\,0015.0231 were used as
comparison and check stars respectively. To have an indication of its
magnitude in the B and V bands, the comparison star was also observed with 
a photoelectric photometer coupled to the Cassegrain focus of the 0.6-m 
telescope at Esteve Duran Observatory.
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\centerline{Figure 1}
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These observations allowed to determine that NSV\,00361 is not an RR Lyrae
but an overcontact eclipsing binary star with an amplitude of 0.43 $\pm$ 0.01 magnitudes at Min. I in the V band of (0\fm 43 $\pm$ 0\fm 02 in B) and 
0.33 $\pm$ 0.01 magnitudes at Min. II (0\fm 33 $\pm$ 0\fm 02 in B). At maximum light,
NSV\,00361 is a 11.75 $\pm$ 0.08 magnitude object in the V band (12\fm 68 $\pm$ 0\fm 16 in B). Figure 1 shows the phase curve of NSV\,00361 in the V band.
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\centerline{2}
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The following ephemeris has been computed for the system:
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\hspace*{3cm} Min.I = HJD\,2450376.43495 + 0\fd 342487 $\times$ E

\hspace*{6.3cm}  $\pm$0.00015 \ $\pm$0.000030

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\beginauthors
 J. VIDAL-SAINZ                         
 J.M. GOMEZ-FORRELLAD                   
 Grup d'Estudis Astronomics             
 Apartado 9481                         
 08080 Barcelona                       
 Spain                                 
 e-mail: vidal@astro.gea.cesca.es       
         jmgomez@astro.gea.cesca.es                           %email

\authorsrightcol
E. GARCIA-MELENDO
Esteve Duran Observator
El Montanya - Seva
08553 Seva, Barcelona
Spain                                   
e-mail: duranobs.astro.gea.cesca.es
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\endauthors


\references

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

Shapley, H.,  Hughes, E.M.,  1934, {\it HA}, {\bf 90}, No.\,4, 163

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