[vsnet-outburst 25957] MisV1448: SU UMa star with a super-long period

[Taichi Kato]

MisV1448: SU UMa star with a super-long period

   Kyoto U. team (I hope observers' detail will be
provided by the team) and Itoh-san have reported observations.
It looks like that the object started developing
superhumps on Oct. 24 with a trend of slower fading rate.
The amplitude reached a peak around 0.45 mag on Oct. 26.
The most likely period is 0.18756(3) d using all the data
since Oct. 24 (probably a mixture of stages A and B).
The data analysis is not complete due to the presence
of secondary extinction term and observations from
the single longitude (Japan).  However, shorter candidate
period could not yield an acceptable phased light curve.

   Observations at different longitudes are strongly
encouraged (still at 13rd mag).

   If this period is confirmed, it is even longer than
0.1628-0.1495 d for ASASSN-18aan (Wakamatsu et al.
in preparation).  See ASASSN-14ho, which has an orbital
period of 0.24315 d, but its SU UMa/WZ Sge-type nature
still needs to be confirmed (Kato 2020).

   The long-waiting time for the appearance of superhumps
of MisV1448 and long duration of stage A (2 d or more)
suggest that this object is mimicking a WZ Sge star,
as is common for SU UMa stars with very long orbital
periods.