[vsnet-alert 9380] SDSS J122740.83+513925.0 superhump period and more

[Taichi Kato]

   As reported by Maehara-san, SDSS J122740.83+513925.0 shows
clear superhumps and eclipses.  A preliminary analysis of the
reported data has yielded a superhump period of 0.06305 d,
and a fractional superhump excess of 1.3% (both values are
preliminary because profiles were affected superposed features).

   The periods are close to those of XZ Eri, reported as
"Deeply Eclipsing SU UMa-Type Dwarf Nova with the Shortest Orbital
Period", cf. Uemura et al. (2004) PASJ 56, S141.

   Uemura et al. wrote:

> During an early phase of the superoutburst, however, the superhump
> period increased, as observed in several short-period systems.
> XZ Eri is a unique object with which we can study the evolution
> of accretion-disk structures through eclipses during the phase of
> the superhump period increase.

   The same would be expected for SDSS J122740.83+513925.0.
Post-superoutburst rebrightening(s) are also expected.
Observers are strongly urged to follow the evolution of this
superoutburst.  We welcome time-resolved CCD photometry data at
vsnet-campaign-report at ooruri.kusastro.kyoto-u.ac.jp .