[vsnet-alert 9421] EK TrA: (late) superhumps persist

Taichi Kato tkato at kusastro.kyoto-u.ac.jp
Sat Jul 21 12:46:09 JST 2007

   Berto Monard has reported further three nights of EK TrA
observations.  The object still shows (late) superhumps.
A period analysis has yielded a refined (late) superhump period
of 0.064350(6) d, 3.3% longer than the orbital period
(0.06228 d).  The object has (mostly linearly) faded at a mean
rate of 0.06 mag/d.

   Although the object looks loke a normal SU UMa-type dwarf
nova (presently just following a superoutburst), the relatively
long persistence of late superhumps and the existence of linear
fading makes some resemblance to WZ Sge-like objects (such as
WX Cet).  The relatively low outburst frequency seems to be
consistent with this intermediate properties between classical
SU UMa-type dwarf novae and WZ Sge-like objects.

According to Kato et al. (2001) PASJ 53, 1191:
System with a short orbital period.  Resembles T Leo
in its outburst behavior.  Photometric studies of superhumps in the
past were not comprehensive enough to draw a conclusion regarding
early superhumps.  The minimum magnitude is taken from Gaensicke et al.
(2001) while Ritter and Kolb (1998) gave an upper limit of V=17.
The maximum magnitude is an extreme value listed in GCVS.  Recent
observations reported to VSNET indicate that the usual magnitudes of
superoutbursts reach V=11.4.

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