[vsnet-alert 121] AL Com entering a new stage

[tkato@kusastro.kyoto-u.ac.jp]

  AL Com seems to have entered a new stage of outburst development.
One manifestation is the appearance of large-amplitude superhumps with a
definitely longer period (cf. preceding article by Nogami & Kato), the
other is a "plateau"-like phase with a slower decline rate as indicated by
the following nightly averaged magnitudes.  In contrast to a rather rapid
(~0.15 mag/day) rate of decline in the early stages (or even more at the
brightness peak, as suggested from a compilation of visual estimates by
T. Vanmunster), the present rate of decline is only 0.05-0.06 mag/day.
We should watch closely what happens next in the present "the best monitored"
WZ Sge-type superoutburst.

  mid-UT   Al-comp S.D.  N  band    V-mag
--------------------------------   ------
950407.643 -0.891 0.026 468 V       12.62
950408.571 -0.754 0.037 291 V       12.76
950409.589 -0.557 0.037  18 V       12.95
950410.627 -0.471 0.036 129 V       13.04
950412.635 -0.242 0.031 292 V       13.27
950413.465 -0.079 0.097   5 V       13.43
950417.562  0.143 0.078 157 V       13.65

Regards,
Taichi Kato and Ouda team

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