\documentstyle[twoside,epsf]{article}

\input ibvs2.sty
\input ibvst.sty

\begin{document}

\IBVShead{4783}{2 November 1999}

\IBVStitle{NSV 09100 is a Short Period Variable in Ophiuchus}

\IBVSauth{Enrique GARCIA-MELENDO$^1$, Florentino S\'ANCHEZ-BAJO$^2$}

\IBVSinst{Esteve Duran Observatory, El Montanya-Seva, 08553 SEVA, Barcelona, Spain,\\ \indent e-mail: duranobs@astro.gea.cesca.es}

\IBVSinst{Departamento de Electronica e Ingenier\'{\i}a Electromec\'anica, Escuela de Ingenier\'{\i}as Industriales, Universidad de Extremadura, Ctra de Elvas s/n, 06071 Badajoz, Spain, e-mail: fsanbajo@unex.es}

\SIMBADobj{NSV 09100}

\begintext

\IBVSTnam{NSV 09100, HV 10963, CSV 003244, GSC 992:1096}

\IBVSTcoo{17\hr 31\mm 35\sec}{+08\deg 09\arcm 13\arcs}{2000.0}

\IBVSTobs{Esteve Duran Observatory, 0.6-m Cassegrain telescope; Extremadura University Observatory, 0.4-m Newton telescope}

\IBVSTdet{CCD}

\IBVSTfil{$V$}

\IBVSTcomp{GSC 992:972}

\IBVSTchk{GSC 992:1077, GSC 992:987, GSC 992:911}

\IBVSTsysn

\IBVSTdata{Upon request}

\IBVSTtyp{ RRc: }

\IBVSTrem{PNSV 09100 was first announced as a variable star by Hughes-Boyce and Huruhata (1942), who indicated that this object was an RR Lyr with a photographic magnitude variation between 13.8 and 14.3. Our observations show that NSV 09100 is a short period variable with a very symmetric light curve, probably of the RRc type, although we do not exclude the possibility of this object being a binary system. The amplitude is 0.40 magnitudes in the $V$ band. The following ephemeris has been computed:
\belowdisplayskip-12pt
$$
{\rm Max.~JD} = 2451290.98(\pm0.03) + 0\fday34196(\pm0.00006)\times E.
$$
}

\IBVSfig{10.5cm}{4783-f1.ps}{}

\reference

Hughes-Boyce, E., Huruhata, M., 1942, HA, 109, No.\ 4

\end{document}
