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\input ibvs2.sty
\input ibvst.sty

\begin{document}

\IBVShead{5156}{16 August 2001}

\IBVStitle{NSV 25616 is a New Classical Cepheid}

\IBVSauth{Baranov, A.B.}

\IBVSinsto{Moscow Astronomical Club, c/o Sternberg Astronomical
Institute, 13 Universitetsky Ave., Moscow 119899,\\ \indent Russia}

\IBVSabs{I report the investigation of a new classical Cepheid on}
\IBVSabs{Moscow archive plates.}

\SIMBADobj{NSV 25616}
\IBVStyp{ DCEP }
\IBVSkey{photometry}

\begintext

\IBVSTnam{NSV~25616 = TYC2 3598 937 1 = GSC 3598.0937 = No.\ 1083 (NGC
7092) (Platais, 1988)}

\IBVSTcoo{21\hr28\mm44\fsec93}{+48\deg58\arcm41\farcs6}{J2000.0}

\IBVSTobs{40-cm astrograph in Crimea}

\IBVSTdet{Photoplate}

\IBVSTfil{None}

\IBVSTcomp{GSC~3598.0695, $B_{\rm pg}=11\fmm 36$;\\
& GSC~3598.0933, $B_{\rm pg}=11\fmm 93$;\\
& GSC~3598.0147, $B_{\rm pg}=12\fmm 25$;\\
& GSC~3598.1205, $B_{\rm pg}=12\fmm 50$}

\IBVSTsys{$B_{\rm pg}$}{Derived from comparison with $B$
magnitudes of the Tycho catalog (ESA, 1997)}

\IBVSTdata{Upon request}

\IBVSTtyp{ DCEP }

\IBVSTrem{
The variability of the star No.\ 1083 in the open cluster NGC 7093 =
M~39, later included in the catalog of suspected variables as
NSV~25616, was supposed by Platais (1988) who had considered it a
possible Cepheid, presumably on the grounds of its spectral type (G2).
We estimated by eye the brightness of the variable on 188 plates from
Moscow archive, JD~2433483--49634. The star is a classical Cepheid with
the following light elements:  $${\rm JD_{max}} = 2441958.37 + 7\fday
9666\times E.$$ The variability range from our estimates is 11\fmm
8--12\fmm 3; this range seems somewhat too small, maybe indicating that
the magnitudes of the comparison stars need improvement. The hump on
the descending branch is characteristic of classical Cepheids with
similar period values.  ${\rm Max-min}=0\fper35$. The phased light
curve is given in Fig.~1.}

\IBVSTack{Thanks are due to S.V. Antipin and N.N. Samus for their
attention and assistance.}

\IBVSfig{5.8cm}{5156-f1.ps}{The phased light curve (a) and the mean
phased light curve (b). Uncertain estimates are
shown as open circles}

\references

ESA, 1997, The Hipparcos and Tycho Catalogues, SP-1200

Platais, I.K., 1988, {\it Nauchnye Informatsii}, No.\ 65, 119

\end{document}


