\documentstyle[twoside,epsf]{article}

\input ibvs2.sty
\input ibvst.sty

\begin{document}

\IBVShead{5125}{22 June 2001}

\IBVStitletl{CCD Light Curves of ROTSE1 Variables, X: GSC 2016:830 B\lowercase{oo},}{ GSC 2022:79 B\lowercase{oo}, GSC 2020:736 B\lowercase{oo} and GSC 2020:873 B\lowercase{oo}}

\IBVSauth{Bl\"attler, E.$^1$; Diethelm, R.$^2$}

\IBVSinst{BBSAG, Sch\"usselacher 1, CH-8636 Wald, Switzerland; e-mail: blaettler-wald@bluewin.ch}

\IBVSinst{BBSAG, Rennweg 1, CH-4118 Rodersdorf, Switzerland; e-mail: diethelm@astro.unibas.ch}

\SIMBADobj{GSC 2016-830}
\SIMBADobj{GSC 2022-79}
\SIMBADobj{GSC 2020-736}
\SIMBADobj{GSC 2020-873}

\begintext

{\bf VAR 1} \hrule

\IBVSTnam{GSC 2016:830 = ROTSE1 J144726.56+224515.0}

\IBVSTcoo{14\hr 47\mm 26.6\sec}{+22\deg 45\arcm 15\arcs}{2000.0}

\IBVSTcomp{GSC 2016:300}

\IBVSTchk{GSC 2016:1146}

{\bf VAR 2} \hrule

\IBVSTnam{GSC 2022:79 = ROTSE1 J145007.78+293858.9}

\IBVSTcoo{14\hr 50\mm 07.8\sec}{+29\deg 38\arcm 59\arcs}{2000.0}

\IBVSTcomp{GSC 2022:287}

\IBVSTchk{GSC 2022:219}

{\bf VAR 3} \hrule

\IBVSTnam{GSC 2020:736 = ROTSE1 J145936.69+250244.9}

\IBVSTcoo{14\hr 59\mm 36.7\sec}{+25\deg 02\arcm 45\arcs}{2000.0}

\IBVSTcomp{GSC 2020:947}

\IBVSTchk{GSC 2020:902}

\newpage

{\bf VAR 4} \hrule

\IBVSTnam{GSC 2020:873 = ROTSE1 J145954.54+255434.1}

\IBVSTcoo{14\hr 59\mm 54.5\sec}{+25\deg 54\arcm 34\arcs}{2000.0}

\IBVSTcomp{GSC  2020:1232}

\IBVSTchk{GSC 2020:659}

\IBVS2fig{7.5cm}{5125-f1.eps}{CCD light curve (without filter) of GSC 2016:830}{5125-f2.eps}{CCD light curve (without filter) of
GSC 2022:79}

\IBVS2fig{7.5cm}{5125-f3.eps}{CCD light curve (without filter) of GSC 2020:736}{5125-f4.eps}{CCD light curve (without filter) of
GSC 2020:873}

\IBVSTobs{Private observatory Sch\"usselacher, Wald, 0.15-m refractor}

\IBVSTdet{SBIG ST-7 CCD camera}

\IBVSTfil{None}

\IBVSTdata{Upon request from diethelm@astro.unibas.ch} %email


\IBVSTtyp{ EW }

\IBVSTrem{
As a byproduct of the ROTSE1 CCD survey, a large number of new
variables have been discovered (Akerlof et al.\ 2000). In a series of
papers, we report unfiltered CCD observations for some of the close
binary systems (type EW) in the list of Akerlof et al.\ (2000). This
installment contains information on four variables in the constellation
Bootes.  The four stars were observed with our CCD equipment as
mentioned above during 5 nights between JD 2451996 and JD 2452041. A
total of 162 CCD frames were measured of GSC 2016:830 (VAR 1), 170
frames of GSC 2022:79 (VAR 2), 156 frames of GSC 2020:736 (VAR 3) and
158 frames for GSC 2020:873 (VAR 4).  Figures 1 through 4 show our
observations folded with the elements
\begin{center}
\begin{tabular}{ll}
GSC 2016:830: & JD(min,hel)${} = 2452001.4032 + 0.361112 \times E$;\\
GSC 2022:79:  & JD(min,hel)${} = 2451996.4139 + 0.301601 \times E$;\\
GSC 2020:736: & JD(min,hel)${} = 2452022.5272 + 0.384641 \times E$;\\
GSC 2020:873: & JD(min,hel)${} = 2451996.5840 + 0.376670 \times E$.\\
\end{tabular}
\end{center}
These elements of variation are deduced from a linear fit to the newly
determined normal minima from the ROTSE1 data (publication in
preparation) and the timings of minima derived from our data given in
Bl\"attler (2001).}

\IBVSTack{This research made use of the SIMBAD data base, operated
at CDS, Strasbourg, France.}

\references

Akerlof, C., Amrose, S., Balsano, R., Bloch, J., Casperson, D., Fletcher,
S., Gisler, G., Hills, J., Kehoe, R., Lee, B., Marshall, S., McKay, T., Pawl,
A., Schaefer, J., Szymanski, J., Wren, J., 2000, {\it AJ}, {\bf 119}, 1901

Bl\"attler, E., 2001, {\it BBSAG Bulletin}, {\bf 125}, in preparation

\end{document}
