[vsnet-outburst 12154] ER UMa: phase reversal in early stage!

[Taichi Kato]

ER UMa: phase reversal in early stage!

   Tom Krajci has reported new observations.  It has become evident
that an unusual phase reversal occurred between Jan. 20 and 21
(cf. http://adsabs.harvard.edu/abs/2003PASJ...55L...7K ).
The period after this reversal has been 0.06534(7) d.
The amplitudes of superhumps have also showed a slight growth
(0.13 -> 0.18 mag) following the phase reversal.
The phenomenon thus appears to be somewhat related to stage B-C
transition in ordinary SU UMa-type dwarf novae.
There is also an indications of short-term oscillations (QPOs?).
Detailed analysis of these period variations and short-term
oscillations will be reported by Ohshima-san.