\documentstyle[twoside, ibvs2, epsf]{article}
\input ibvse.sty

\begin{document}

\IBVShead{5399}{1 April 2003}

\IBVStitle{New Times of Minima of Eclipsing Binary Systems}

\IBVSauth{Baki\c{s}, V.$^1$; T\"{u}ys\"{u}z, M.$^1$; Zejda, M.$^2$; Soydugan, F.$^1$; Soydugan, E.$^1$; Kabas, A.$^1$; Dogru, S. S.$^1$; Erdem, A.$^1$; Budding, E.$^1$; Dem\.{i}rcan, O.$^1$; Ozdemir, S.$^1$; \c{C}icek, C.$^1$, Bulut,~A.$^1$}

\IBVSinst{Ulupinar Astrophysics Observatory, \c{C}anakkale Onsekiz Mart University, TR-17100, \c{C}anakkale, Turkey}

\IBVSinst{N. Copernicus Observatory and Planetarium in Bruno, Kravi hora 2, 616 00 Brno, Czech Republic}

\SIMBADobj{RT And} 
\SIMBADobj{WZ And} 
\SIMBADobj{AB And}
\SIMBADobj{TT Aur} 
\SIMBADobj{IU Aur} 
\SIMBADobj{TY Boo}
\SIMBADobj{UW Boo} 
\SIMBADobj{CK Boo} 
\SIMBADobj{RZ Cas}
\SIMBADobj{DK Cep} 
\SIMBADobj{SW Cyg} 
\SIMBADobj{V859 Cyg}
\SIMBADobj{AX Dra} 
\SIMBADobj{UX Eri} 
\SIMBADobj{RX Gem}
\SIMBADobj{AP Leo} 
\SIMBADobj{PY Lyr} 
\SIMBADobj{ER Ori}
\SIMBADobj{BN Peg} 
\SIMBADobj{II Per} 
\SIMBADobj{V432 Per}
\SIMBADobj{XY Sct} 
\SIMBADobj{AH Tau} 
\SIMBADobj{XY UMa}
\SIMBADobj{RU UMi}

\begintext

\IBVSEobs{40-cm f/10 Meade Cassegrain-Schmidt telescope of the
\c{C}anakkale Onsekiz Mart University Ulupinar Astrophysics Observatory\\
30-cm f/3.3 Meade Cassegrain-Schmidt telescope of the
\c{C}anakkale Onsekiz Mart University Ulupinar Astrophysics
Observatory}

\IBVSEred{Reduction of the CCD frames was made with
MUNIPACK\footnotemark\ software, and reduction of photoelectric
observations was made by ATMEX\footnotemark\ software.}

\footnotetext[1]{Hroch, F., Nov\'ak, R., 1997, MUNIPACK,
{\tt http://munipack.astronomy.cz/}}

\footnotetext[2]{Keskin, V., 2001, ATMEX,
{\tt http://astronomy.sci.ege.edu.tr/~{}keskinv/}}

\IBVSEmethod{Kwee -- van Woerden method (Kwee \& van Woerden,
1952), and in some cases, depending on the nature of the data set,
several procedures written by A. Gaspani (1995) based on
artificial neural networks were used.}

{\small
\IBVSEstars{
RT And   & EA & 23 11 10 & +53 01 34 & GSC\,3998:1794 & 36697.8570 & 0.63893088 & 1 \\
WZ And   & EB & 01 01 43 & +38 05 46 & GSC\,2799:0396 & 46025.7264 & 0.69566096 & 1 \\
TT Aur   & EB & 05 09 42 & +39 35 10 & GSC\,2899:0492 & 21242.2517 & 1.33273455 & 1 \\
IU Aur   & EB & 05 27 52 & +34 46 58 & GSC\,2411:1292 & 38448.4050 & 1.81147464 & 1 \\
TY Boo   & EW & 15 00 47 & +35 07 52 & GSC\,2568:0997 & 47612.6035 & 0.31714910 & 1 \\
UW Boo   & EA & 14 20 59 & +47 06 43 & GSC\,3472:0388 & 42404.7175 & 1.00471105 & 1 \\
CK Boo   & EW & 14 35 03 & +09 06 54 & GSC\,0910:0447 & 46183.5950 & 0.35515320 & 1 \\
RZ Cas   & EA & 02 48 56 & +69 38 03 & GSC\,4312:1101 & 48960.2260 & 1.19524980 & 1 \\
DK Cep   & EA & 21 58 33 & +60 56 53 & GSC\,4262:2154 & 33590.5578 & 0.98590874 & 1 \\
EG Cep   & EB & 20 15 57 & +76 48 36 & GSC\,4589:2757 & 40050.4491 & 0.54462274 & 2 \\
SW Cyg   & EA & 20 06 28 & +46 17 59 & GSC\,3559:0857 & 43692.3967 & 4.57294500 & 1 \\
V859 Cyg & EW & 19 27 12 & +28 56 50 & GSC\,2137:1452 & 34629.4119 & 0.40499999 & 1 \\
} }
{\small
\IBVSEstars{
AX Dra   & EB & 12 40 14 & +66 17 08 & GSC\,4168:0342 & 26767.6886 & 0.56816285 & 1 \\
UX Eri   & EW & 03 09 53 & $-$06 53 50 & GSC\,4714:0029 & 41922.3338 & 0.44528205 & 1 \\
RX Gem   & EA & 06 50 11 & +33 14 21 & GSC\,2440:1031 & 40555.8370 & 12.2085250 & 1 \\
AP Leo   & EW & 11 05 05 & +05 09 06 & GSC\,0268:0779 & 39536.5429 & 0.43035716 & 1 \\
PY Lyr   & EW & 19 20 26 & +28 56 44 & GSC\,2136:3105 & 34980.4372 & 0.38576273 & 1 \\
ER Ori   & EW & 05 11 14 & $-$08 33 23 & GSC\,5330:0364 & 43090.5300 & 0.42339943 & 1 \\
BN Peg   & EA & 21 28 02 & +05 00 12 & GSC\,5370:0247 & 33896.3700 & 0.71329807 & 1 \\
II Per   & EB & 04 29 37 & +44 25 32 & GSC\,2891:2911 & 30257.5500 & 0.47985400 & 3 \\
V432 Per & EW & 03 10 10 & +42 51 21 & GSC\,2855:0535 & 48601.3776 & 0.38330910 & 1 \\
XY Sct   & EW & 18 41 07 & $-$06 04 31 & USNO\,0825:12607174 & 28729.5293 & 0.7852563 & 3 \\
AH Tau   & EW & 03 47 12 & +25 07 02 & GSC\,1804:2309 & 31822.3653 & 0.33267368 & 1 \\
XY UMa   & EB & 09 09 56 & +54 29 26 & GSC\,3805:0479 & 35216.5018 & 0.47899493 & 1 \\
RU UMi   & EB & 13 38 57 & +69 48 12 & GSC\,4402:1049 & 41596.3365 & 0.52492618 & 1 \\
} }

\IBVSEsource{
1. Kreiner et al., 2001; \\
2. Demircan et al., IBVS, 5364, 2003; \\
3. GCVS 4th edition, electronic version 2001.
}

\IBVSEmin{
RT~And       & 52577.3991  & 7     & II   & $ - $  &  $-0.0192$     & ccd \\
WZ~And       & 52577.4507  & 1     & I    & $ - $  &  $-0.0107$     & ccd \\
TT~Aur       & 52595.5079  & 9     & II   & $ - $  &  $0.0096 $     & ccd \\
IU~Aur       & 52699.2737  & 2     & I    & $ - $  &  $-0.0023$     & ccd \\
             & 52698.3748  & 7     & II   & $ - $  &  $0.0045 $     & ccd \\
TY~Boo       & 52707.4509  & 1     & I    & $ - $  &  $0.0057 $     & ccd \\
UW~Boo       & 52710.5313  & 5     & II   & $ - $  &  $-0.0098$     & ccd \\
CK~Boo       & 52462.3796  & 6     & I    &$B,V,R$ &  $0.0312 $     & pe \\
RZ~Cas       & 52539.4113  & 7     & II   &$ B,V $ &  $0.0097 $     & pe \\
DK~Cep       & 52553.5256  & 1     & I    & $ - $  &  $-0.0009$     & ccd \\
EG~Cep       & 52654.3718  & 7     & II   & $ - $  &  $-0.0112$     & ccd \\
SW~Cyg       & 52509.2909  & 2     & I    & $ - $  &  $0.2562 $     & ccd \\
V859~Cyg     & 52577.2311  & 8     & II   & $ - $  &  $0.0384 $     & ccd \\
AX~Dra       & 52721.3642  & 1     & I    & $ - $  &  $-0.0034$     & ccd \\
UX~Eri       & 52569.5092  & 7     & I    & $ - $  &  $0.0363 $     & ccd \\
RX~Gem       & 52654.6485  & 7     & I    & $ - $  &  $0.1632 $     & ccd \\
AP~Leo       & 52713.4024  & 1     & II   & $ - $  &  $-0.0312$     & ccd \\
PY~Lyr       & 52476.3842  & 2     & I    & $ - $  &  $0.0641 $     & ccd \\
             & 52477.3479  & 6     & II   & $ - $  &  $0.0634 $     & ccd \\
ER~Ori       & 52656.3972  & 4     & I    & $ - $  &  $0.0038 $     & ccd \\
BN~Peg       & 52551.2478  & 5     & I    & $ - $  &  $-0.0066$     & ccd \\
II~Per       & 52552.4762  & 2     & I    & $ - $  &  $-0.0504$     & ccd \\
V432~Per     & 52578.4229  & 2     & II   & $ - $  &  $0.0218 $     & ccd \\
XY~Sct       & 52474.3912  & 3     & II   & $ - $  &  $-0.1107$     & ccd \\
AH~Tau       & 52578.4707  & 1     & I    & $ - $  &  $-0.0662$     & ccd \\
XY~UMa       & 52707.2102  & 11    & II   & $ - $  &  $-0.0310$     & ccd \\
RU~UMi       & 52656.5193  & 6     & I    & $ - $  &  $-0.0118$     & ccd \\
}

\IBVSErem{The 25 stars, whose details are listed in Table 1, were
observed using either conventional filtered Johnson standard
($BVR$) photoelectric photometry with the SSP-5A or unfiltered
with the ST-237. 27 times of minima, primary and some secondary,
are listed in Table 2, together with $O-C$ values corresponding to
the Table~1 ephemerides. The remarks column of Table 2 gives an
identification of which system was used; thus ``ccd'' refers to
the 30 cm + ccd combination and ``pe'' means
the single channel photometer on the 40 cm telescope.\\
The RS CVn binaries RT And and XY UMa show distorted light curves,
so the determination of their minima may be subject to apparent
variations due to maculation effect (cf.\ Olah, 2003), however
Demircan (1999) has argued that these effects can be separated
from genuine period changes over sufficiently long intervals of
time. The classical Algols RX Gem and SW Cyg could be expected to
follow inverted parabolic trends corresponding to the evolution of
these systems. SW Cyg seems to have a cyclic variation superimposed
on this, however, (cf.\ Kreiner et al., 2001) the remaining
binaries in this sample generally show more complex variations of
period which call for ongoing close attention to characterize.}

\IBVSEdata{Upon request}

\IBVSEack{This work was partly supported by the Research Found of
\c{C}anakkale Onsekiz Mart University.}

\references

Demircan, O., 1999, {\it Tr.J. of Physics}, {\bf 23}, 425

Demircan et al., 2003, {\it IBVS}, 5364

Gaspani, A., 1995, {\it 3rd GEOS workshop on variable star data
acquisition and processing techniques}, 13-14 May 1995, S.
Pellegrino Terme, Italy

Kreiner, M. J., Kim, C.-H. and Nha, I.-S., 2001,
{\it An Atlas of $O-C$ Diagrams of Eclipsing
Binaries, Krak\'{o}v}.

Kwee, K. K., \& van Woerden, H., 1956, {\it Bull.\ Astron.\ Inst.\
Neth.}, {\bf 12}, 327.

Ol\'ah, K., Proc. Workshop, New Directions in Close Binary Studies
{\it ``The Royal Road to the stars''}, Kluwer, (in press).

\endreferences

%From IBVS 5464
\IBVSerratum{5399}

Time of minimum of AH~Tau was given as 52578.4707, but it should be 52578.5104.



\end{document}
