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We report unfiltered CCD photometry of the first confirmed superoutburst in 2010 April of the recently discovered dwarf nova SDSS J083931.35+282824.0. From a quiescence magnitude of ∼19.8 it rose to 14.0, an outburst amplitude of at least 5.8 magnitudes. Only the plateau phase of the outburst was observed, during which superhumps with peak-to-peak amplitude of up to 0.28 magnitudes were present, confirming this to be an SU UMa-type dwarf nova. The mean superhump period was Psh= 0.07836(2) during the first 3 days and this subsequently decreased to 0.07800(3)d. Analysis of the data revealed tentative evidence for an orbital period Porb= 0.07531(25)d. The fractional superhump period excess was ϵ= 0.039(6), which is consistent with other dwarf novae of similar orbital period. [ABSTRACT FROM AUTHOR]

We present photometry of the first reported superoutburst, during 2008 January and February, of the dwarf nova VSX J074727.6+065050. At its brightest the star reached magnitude 11.4 and this was followed by a slow decline at 0.09 mag/d for 19 days, corresponding to the plateau phase. There was then a rapid decline at 1.66 mag/d to a temporary minimum at magnitude 16.6 where it stayed for two to three days, after which there were six remarkable echo outbursts before the star gradually faded back towards quiescence at ∼magnitude 19.5. The overall outburst amplitude was at least 8 magnitudes and it lasted more than 80 days. During the plateau phase we observed common superhumps with Psh = 0.06070(6)d, but the period increased to Psh = 0.06151(5)d coinciding with the end of the plateau phase and the onset of the rapid decline. This corresponds to a continuous period change with P = +4.4(10) × 10-5. During the echo outbursts there was a superhump regime with Psh = 0.06088(49)d. Evidence is presented which is consistent with the star being a member of the WZ Sge family of dwarf novae. [ABSTRACT FROM AUTHOR]