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We report unfiltered photometry during superoutbursts of PU UMa in 2009 and 2012. The amplitude was 4.5 magnitudes above mean quiescence and lasted at least 9 to 10 days. Superhumps were present with a peak-to peak amplitude of up to ~0.3 mag, thereby confirming PU UMa to be a member of the SU UMa family of dwarf novae. The mean superhump period during the later part of the 2012 outburst was Psh = 0.08076(40)d. Analysis of the eclipse times of minimum, supplemented with data from other researchers, revealed an orbital period of Porb= 0.077880551(17)d. The superhump period excess was e= 0.037(5). During the 2012 outburst, which was the better observed of the two, the FWHM eclipse duration gradually declined from 9.5 to 5 min. The eclipse depth was up to 1.7 magnitudes. [ABSTRACT FROM AUTHOR]

We report unfiltered photometry of BG Arietis (= SDSS J015151.87+140047.2) in 2009 and 2010 which shows the presence of superhumps with peak-to-peak amplitude of up to 0.36 magnitudes, showing this to be an SU UMa type dwarf nova. The outburst amplitude was 5.1 mags above a mean quiescence magnitude of 19.9. The 2010 event lasted at least 20 days during which we observed a precursor outburst which was immediately followed by a superoutburst. Modulations were observed during the rise to superoutburst with a period approximately half Porb. The mean superhump period during the plateau phase was Psh= 0.0849(6)d, representing a superhump period excess ε= 0.030(7). We also observed small eclipses of depth 0.06 to 0.13 magnitude and FWHM duration of ∼12 mins (ΔΦ1/2= 0.10), which we interpret as grazing eclipses of the accretion disc. The 2009 superoutburst was less well observed, especially in the early stages, so we cannot tell whether there was a precursor outburst. The mean superhump period during the plateau was Psh= 0.0851(4)d, but towards the end of the plateau it suddenly decreased to Psh= 0.0845(11)d. Small eclipses were also observed. [ABSTRACT FROM AUTHOR]

We report the discovery of a new dwarf nova and observations of its first confirmed superoutburst during 2009 October. The outburst amplitude was 6 magnitudes. The main outburst lasted 17 days and was followed 4 days later by a remarkable rebrightening. Superhumps were present during the main outburst, which confirms that it belongs to the SU UMa family. Initially the mean superhump period was Psh= 0.06965(17)d, but analysis of the O-C residuals showed a dramatic evolution in Psh during the outburst. During the first two-thirds of the plateau phase the period increased with dPsh/dt = +1.24(5)×10-3. There was then an abrupt change following which the period decreased with dPsh/dt = -1.01(9)×10-3. The amplitude of the superhumps also varied, with a maximum amplitude near the beginning of the outburst and a second maximum corresponding to the discontinuity in Psh. Analysis of archival data showed that outbursts also occurred in 2005 October, 2006 June and 2007 June. Assuming that the superoutbursts are periodic, we estimate that the outburst period is around 450 days. [ABSTRACT FROM AUTHOR]