AB Nor: A new member of SU UMa-type dwarf novae
April outburst
The dwarf nova AB Nor experienced a rare outburst (14.4mag) as reported
by R. Stubbings and A. Pearce on April 1. According to A. Pearce,
the last outburst of AB Nor occurred in 1999 May (mv=14.7, positively
recorded on three nights)
(vsnet-alert 4568).
After rapid declining to <15.2mag on April 5, R. Stubbings
reported a remarkable rebrightening (14.0mag) on April 6.
(vsnet-alert 4574,
vsnet-alert 4578,
vsnet-alert 4594).
Superhump detection
On April 8, W. S. G. Walker performed a run of 2.8
hours and measured one definite superhump with an amplitude of 0.4
magnitudes. Maximum was at Apr 08.55 and the period looked about 2 hours,
perhaps as much as 2.2 hours. He also commented that it is very uncertain
in the absence of a second peak
(vsnet-alert 4589).
(Light curve of AB Nor on April 8 during the first confirmed superoutburst
presented by W. S. G. Walker;
vsnet-alert 4590)
From time-series observations on April 8 and 9, he estimate
a superhump period to be around 0.078 to 0.079 d. The amplitude appeared
smaller at ~0.3 magnitudes but the humps still have a sharp rise with some
structure on the decline.
(vsnet-alert 4597).