[vsnet-campaign-dn 4871] OT_J055718+683226: Superhump phase shift?

[uemuram at hiroshima-u.ac.jp]

OT_J055718+683226: Superhump phase shift?

    This ultra-short period dwarf nova is still in a superoutburst.

20061218.65324 15.170 0.004 V
20061219.70913 15.248 0.002 V
20061221.72843 15.503 0.004 V
20061222.74022 15.572 0.003 V

Our observation on 22 Dec. indicates that superhumps dramatically 
changed their profile and the secondary maxima of past superhumps 
are now prominent.

  http://home.hiroshima-u.ac.jp/hasc/kanata/j0557/index.html

As can be seen in the above page, the superhump phase has  
apparently been shifted.  A possible growth of the secondary maximum 
is also seen in the light curve on 19 Dec.

Time-series observations are urged in order to study the nature
of this superhump evolution.

Regards,
Makoto Uemura and Akira Arai
Hiroshima University