[vsnet-alert 22613] ASASSN-18ey = MAXI J1820+070: rapid brightening

[Yasuyuki WAKAMATSU]

ASASSN-18ey = MAXI J1820+070: rapid brightening

Tonny Vanmunster, Geoff Stone, Vihorlat observatory team
(Pavol A. Dubovsky, Tomas Medulka), Josch Hambsch, Kyoto U. team,
Stephen Brincat, Berto Monard, Itoh-san, Crimean Astrophys. Obs. team
and Ian Miller reported further observations.

The magnitude once have dropped to 14.6 mag on October 3, and rapidly
returns to 14.1 mag now. This brightening after the rapid dropping of
magnitude
indicates the object entered an unknown physical state. The object still
shows
superhump-like modulations with the period of 0.6897(2) d. The O-C diagram
suggests these modulations looks like stage B superhumps on the basis of
the
gradually change of the period.

Further continuous observations are encouraged.