[vsnet-alert 9543] HS2331+3905: early humps!!

[uemuram at hiroshima-u.ac.jp]

HS2331+3905: observation with KANATA

Last night we observed HS2331+3905 for one hour.

http://kanatatmp.blogspot.com/2007/09/hs23313905rapidly-brightening.html

The figure in the above URL shows V, J and Ks-band light curves. 
We find a rapid brightening and a color of V-J~0.8. 
The color indicates that the system was very red compared 
with the colors of dwarf novae in outburst yesterday.
These results suggest that the outburst had just begun.

We observed HS2331+3905 also today.

http://kanatatmp.blogspot.com/2007/09/hs23313905early-hump.html

The figure in the above URL shows the light curve in 
V-band for about 7.5 hours. 
We detected humps, perhaps early humps observed in WZ Sge type 
dwarf novae, whose period is about 0.057±0.01 day.

Regards,
R. Matsui, M. Uemura, A. Arai, M. Sasada, O. Nagae
on behalf of the KANATA team
Hiroshima University