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\IBVShead{5129}{25 June 2001}

\IBVStitletl{The First Ground-based Photometric}{ Observations of V397 Cephei}

\IBVSauth{Bulut, \.{I}.$^{1}$; Dem\.{i}rcan, O.$^{1}$; Erdem, A.$^{1}$; \c{C}\.{i}\c{c}ek, C.$^{1}$; \"Ozdem\.{i}r, S.$^{1}$; Soydugan, F.$^{1}$; \\ \indent Soydugan, E.$^{1}$; De\u{g}\.{i}rmenc\.{i}, \"{O}.L.$^{2}$; Bozkurt, Z.$^{2}$; Yakut, K.$^{2}$; Eseno\u{g}lu, H.$^{3}$; \\ \indent Heged\"{u}s, T.$^{4}$; Borkovits, T.$^{4}$; B\'{i}r\'{o}, I.B.$^{4}$}

\IBVSinst{\c{C}anakkale Onsekiz Mart University, Faculty of Arts and
Sciences, Department of Physics,\\ \indent TR-17100 \c{C}anakkale,
Turkey, ibulut@comu.edu.tr, demircan@comu.edu.tr} %email


\IBVSinst{Ege University Observatory, TR-35100 Bornova, \.{I}zmir,
Turkey}

\IBVSinst{\.{I}stanbul University Observatory, TR-34452 \.{I}stanbul,
Turkey}

\IBVSinst{Baja Astronomical Observatory of B\'{a}cs-Kiskun County,
Baja, Szegedi \'{u}t, P.O. Box 766, H-6500, Hungary}

\SIMBADobjAlias{V397 Cep}{HD 225093}

\begintext

\IBVSTnam{V397 Cep = BD +72\deg1136 = HIP 270 = HD 225093}

\IBVSTcoo{00\hr03\mm24\fsec01}{+73\deg10\arcm28\farcs2}{2000}

\IBVSTobs{T\"{U}B\.{I}TAK National Observatory, 40-cm Cassegrain
telescope}

\IBVSTdet{Hamamatsu, R 4457 (PMT)}

\IBVSTfil{Johnson $U$, $B$ and $V$}

\IBVSTcomp{BD +72\deg1135 = HIP 128}

\IBVSTchk{BD +72\deg12 = HD 1176}

\IBVSTsysn

\IBVSTdata{Upon request}

\IBVSTtyp{ EA }

\newpage

\IBVSfig{10cm}{5129-f1.ps}{$U$, $B$ and $V$ light, and $U-B$ and $B-V$
color curves of V397 Cep. The color curves do not seem to have any
variation}

\IBVSTrem{
The variability of V397 Cep was discovered by HIPPARCOS (ESA,
1997). The photometric observations of the system by HIPPARCOS show an
Algol type light curve with an amplitude of 0\fmm418. The visual
magnitude of the system varies between 7\fmm393 and 7\fmm811. The mean
orbital period derived from the best HIPPARCOS light curve fit is
2\fday08684 and the epoch of minimum light is given as HJD 2448501.1800
(ESA, 1997). The spectral type of the system is given as A2. The first
ground-based photometric observations were made over 11 nights during
2000 observing season at the T\"{U}B\.{I}TAK (Scientific and Technical
Research Council of Turkey) National Observatory. The light and color
curves, which were obtained by these observations, are given in
Figure~1. New light curves show that the secondary minimum clearly lies
not at the phase of 0.5 as usually expected, but shifted to the phase
of 0.573. The asymmetry and duration of both minima are quite
different. Therefore, the orbit of the binary should be quite eccentric
and the system should be a good candidate for eclipsing binaries with
apsidal motion. Further observations of the system are needed in
finding the apsidal motion parameters.}

\IBVSTack{ We acknowledge the observing time at the
T\"{U}B\.{I}TAK National Observatory. This work was supported by
\c{C}anakkale Onsekiz Mart University Research Fund. }

\reference

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

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