[Message Prev][Message Next][Thread Prev][Thread Next][Message Index][Thread Index]

[vsnet-alert 7636] BC UMa: superoutburst! growth of genuine superhumps!



BC UMa: superoutburst! growth of genuine superhumps!

Dear Colleagues,

   We have received new sets of data from David Boyd and Kazuhiro
Nakajima-san.  Boyd's observation covered the important part of the early
stage, which showed a slightly decayed early modulations (early superhumps?).
Nakajima-san's 8-hr long observation last night clearly shows the growth
of genuine superhumps (ampliude growing to 0.1 mag).  The period of the
signal is slightly longer than 0.064 d, which qualifies the signal as the
genuine superhumps!  However, the profile of these humps is slightly unlike
those of usual SU UMa-type superhumps, particularly in that the rise is
slower and there is some tendency of a double wave.  It is possible,
as in the transition of WZ Sge from early superhumps to genuine superhumps,
the major peak of the early double-wave modulations eventually developed
into genuine superhumps.  BC UMa would become a key object in clarifying
the peculiar behavior of WZ Sge-type dwarf novae!

   We have also received additional notes of successful observations during
the past two days.  We hope we will be able to fully illustrate the growth
of superhumps in the very important system BC UMa.

   Further observations are very strongly encouraged.  Please also send your
observations to Uemura-san (uemura@kusastro.kyoto-u.ac.jp) and Ishioka-san
(ishioka@kusastro.kyoto-u.ac.jp) in order to avoid a delay in communication.

Regards,
Taichi Kato
VSNET Collaboration team

VSNET Home Page

Return to Daisaku Nogami


vsnet-adm@kusastro.kyoto-u.ac.jp