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تسجيل مستخدم جديدA photometric study of the newly discovered eclipsing cataclysmic variable SDSS J040714.78-064425.1
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We present the results obtained from unfiltered photometric CCD observations of the newly discovered cataclysmic variable SDSS J040714.78-064425.1 made during 7 nights in November 2003. We establish the dwarf nova nature of the object as it was in outburst during our observations. We also confirm the presence of deep eclipses with a period of 0.17017d+/-0.00003 in the optical light curve of the star. In addition, we found periods of 0.166d+/-0.001 and possibly also 5.3d+/-0.7 in the data. The 0.17017d periodicity is consistent within the errors with the proposed orbital period of 0.165d (Szkody et. al. 2003) and 0.1700d (Monard 2004). Using the known relation between the orbital and superhump periods, we interpret the 0.166d and 5.3d periods as the negative superhump and the nodal precession period respectively. SDSS J040714.78-064425.1 is then classified as a negative superhump system with one of the largest orbital periods.
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