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\begin{document}

\IBVShead{5914}{9 December 2009}

\IBVStitle{V1032 Oph Is A Dwarf Nova}

\IBVSauth{Wils, Patrick$^1$; Henden, Arne A.$^2$}
\IBVSinst{Vereniging Voor Sterrenkunde, Belgium; e-mail: patrickwils@yahoo.com}
\IBVSinst{American Association of Variable Star Observers}

\SIMBADobj{V1032 Oph}
\GCVSobj{V1032 Oph}

\IBVStyp{ CV, UG }
\IBVSkey{Variable stars, Cataclysmic variables, Dwarf novae}
\IBVSabs{Photometric observations show that V1032 Oph is a dwarf nova with a short outburst cycle.}

\begintext

V1032~Oph was discovered by Kinman et al. (1965, their star number 40) as a possible RR~Lyrae type variable.
It had however an unusually large photographic amplitude of about two magnitudes and Kinman et al. could not find a suitable period.  
GALEX (Martin et al., 2005) visited the object three times, with near UV magnitudes $nuv = 18.9$ and $17.8$ on two occasions in 2005
(and no far UV magnitude $fuv$ determined),
and with $fuv = 20.4\pm0.4$ and $nuv = 20.2\pm0.2$ in 2007.  
The Catalina Real-time Transient Survey (CRTS; Drake et al., 2009) rediscovered V1032~Oph recently (as CSS080426:162610-035325).
The CRTS light curve was not characteristic for RR Lyrae type stars.
\\
\IBVSshortlink{http://nesssi.cacr.caltech.edu/catalina/20080426/804260040884140372p.html}{CRTS light curve} 

V1032~Oph was therefore selected for follow-up observations using the robotic mode of the C14 telescope at the Sonoita Research Observatory (SRO).
Photometry was performed using a SBIG STL-1001E CCD camera equipped with $B$ and $V$ filters.
The stars USNO-B1.0~0861-0298934 ($V = 14.98\pm0.02$, $B-V = 0.97\pm0.05$, star "a" of Kinman et al.) 
and USNO-B1.0~0860-0285298 ($V = 15.88\pm0.13$, $B-V = 0.81\pm0.05$) were used as comparison stars for the SRO observations.
Their $B$ and $V$ magnitudes were determined from absolute photometry at SRO.
In general two $B$ and two $V$ images with exposures of 300 seconds were made each available night.
These observations, taken in the first half of 2009, 
are available from the IBVS website.
\\
\IBVSedata{5914-t1.txt}
\IBVSdataKey{5914-t1.txt}{V1032 Oph}{photometry}
\IBVSedata{5914-t2.txt}
\IBVSdataKey{5914-t2.txt}{V1032 Oph}{photometry}


The light curve of V1032~Oph presented in Fig.~1 is similar to that of SU~UMa, with frequent short outbursts 
and a generally fairly small amplitude for a dwarf nova ($V$ varies between 15.1 and 19.0, but maxima are generally around mag. 16 and minima around mag. 18.5).
Also the data of Kinman et al. (1965) and early CRTS observations are compatible with this interpretation.
The outburst that started at the end of March 2009 and lasted into April, was brighter and lasted longer than any of the other outbursts.
This could therefore have been a superoutburst.
The CRTS light curve shows a period of about four months in the first half of 2007 when the object was always near minimum 
without any outbursts (unfiltered mag. 17-17.5; note that the unfiltered CRTS observations have the object in general about one magnitude brighter than in $V$).
Also SU~UMa has experienced such extended spells in quiescence in the past.
During maximum V1032~Oph has $B-V = 0.26\pm0.10$ on average, within the range of cataclysmic variables.  
This value may need to be corrected for interstellar extinction ($E(B-V) = 0.282$ in the direction of V1032~Oph, according to Schlegel et al., 1998).

\IBVSfig{9.5cm}{5914-f1.eps}{Light curve of V1032~Oph in the first half of 2009 from CRTS (open circles; unfiltered) and SRO data (filled circles)
using nightly averages.  To guide the eye, some points have been connected by lines.}
\IBVSfigKey{5914-f1.eps}{V1032 Oph}{Light curve}


%\newpage
{\bf Acknowledgements:}
This study made use of the Simbad and VizieR database (Ochsenbein et al., 2000), 
and of data provided by the Catalina Real-time Transient Survey and the NASA GALEX mission.


%\newpage
\references

Drake A.J., Djorgovski S.G., Mahabal A., Beshore E., Larson S., Graham M.J., Williams R., Christensen E., Catelan M., Boattini A., Gibbs A., Hill R., Kowalski R., 2009, {\it ApJ}, {\bf 696}, 870

Kinman T.D., Wirtanen C.A., Janes K.A., 1965, {\it ApJ Suppl}, {\bf 11}, 223

Martin D.C., Fanson J., Schiminovich D., Morrissey P., Friedman P.G., Barlow T.A., Conrow T., Grange R., 
Jelinsky P.N., Milliard B., Siegmund O.H.W., Bianchi L., Byun Y.-I., Donas J., Forster K., Heckman T.M., 
Lee Y.-W., Madore B.F., Malina R.F., Neff S.G., Rich R.M., Small T., Surber F., Szalay A.S., Welsh B., 
Wyder T.K., 2005, {\it ApJ}, {\bf 619}, L1

Ochsenbein F., Bauer P., Marcout J., 2000, {\it A\&A Suppl.}, {\bf 143}, 23

Schlegel D.J., Finkbeiner D.P., Davis M., 1998, {\it ApJ}, {\bf 500}, 525

\endreferences

\end{document}


