\documentstyle[twoside,epsf]{article}

\input ibvs2.sty
\input ibvst.sty

\begin{document}

\IBVShead{4937}{10 August 2000}

\IBVStitletl{New Times of Minima}{ and Revised Ephemeris of BC Eridani}

\IBVSauth{Nagai, Kazuo$^1$; Kiyota, Seiichiro$^2$}

\IBVSinst{B-305 5-9-3 Honson, Chigasaki, 253-0042 Japan, email: PXS10547@nifty.ne.jp}

\IBVSinst{1-401-810 Azuma, Tsukuba, 305-0031 Japan, email: skiyota@abr.affrc.go.jp}

\SIMBADobjAlias{BC Eri}{HIP 22234}

\begintext

\IBVSTnam{BC Eri = HIP 22234}

\IBVSTcoo{04\hr46\mm59\fsec00}{$-14\deg37\arcm23\farcs3$}{2000.0}

\IBVSTobs{10-cm Reflector (fl\,=\,600 mm) (KN)\\
25-cm Schmidt--Cassegrain (fl\,=\,1600 mm) (SK)}

\IBVSfig{8.75cm}{4937-f1.ps}

\IBVSTdet{SBIG ST-5 CCD camera (KN); 
Apogee AP-7 CCD camera (SK)}

\IBVSTfil{Johnson $V$ (KN);
Johnson--Cousins $V$ and $I_c$ (SK)}

\IBVSTcomp{GSC 5328:1509 = SAO 149875 (KN)\\
& GSC 5328:1449 (SK)}

\IBVSTchk{GSC 5328:1765 (SK)}

\IBVSTsysn

\IBVSTdata{Upon request}

\IBVSTtyp{ EW }

\IBVSTrem{
BC Eri was discovered by Hoffmeister (1936). Guriev (1938) assigned it
as a cluster variable (Max = HJD $2428869.791 + 0\fday26393\times E$).
Ashbrook \& Gossner (1945) gave improved ephemeris (Max = HJD
$2428869.791 + 0\fday26389458\times E$) from their observations and
Harvard plates archives. Fitch (1966) assigned this star as an EW type
variable with period of 0\fday528 from his multicolor photoelectric
photometry. The fourth edition of General Catalogue of Variable Stars
(Kholopov et al.\ 1986) listed its period as 0\fday52778916 with no
epoch of minimum. The period in HIPPARCOS catalog (ESA 1997) is
0\fday527242. We observed this star from 1998 to 2000 and got the
following new moments of minima.
\begin{center}
\begin{tabular}{lccc}
\hline
Min (HJD) & Type of min. & Filter & Observer \\
\hline
2451138.10010 & II & $V$ & KN \\
2451176.06170 & II & $V$ & KN \\
2451477.11570 & II & $V$ & SK \\
2451493.19719 & I & $I_c$ & SK \\
2451501.10729 & I & $V$ & SK \\
2451502.15987 & I & $I_c$ & SK \\
2451515.08101 & II & $V$ & SK \\
2451525.09784 & II & $I_c$ & SK \\
2451526.14810 & II & $V$ & SK \\
2451529.05185 & I & $I_c$ & SK \\
2451538.01430 & I & $V$ & KN \\
2451548.03010 & I & $V$ & SK \\
\hline
\end{tabular}
\end{center}
We calculated the following new ephemeris from our observations.
\belowdisplayskip-12pt
$${\rm Min = HJD}~2451501.10674970+0\deg5272429\times E.$$
}

\references

Ashbrook, J. and Gossner, J., 1945, {\it Astronomical Journal}, {\bf 52}, 56

ESA, 1997, The Hipparcos \& Tycho Catalogues, ESA SP-1200

Fitch, W.S., 1966, {\it IBVS}, No.\ 132

Guriev, N., 1938, {\it Tadjik Circ.}, No.\ 36

Hoffmeister, C., 1936, {\it Astronomische Nachrichten}, {\bf 258}, 39

Kholopov P.N. et al., 1986, General Catalog of Variable Stars 4th ed.

\end{document}
