[vsnet-alert 22622] ASASSN-18ey = MAXI J1820+070: fading again and collapse of superhumps?

[Yasuyuki WAKAMATSU]

ASASSN-18ey = MAXI J1820+070: fading again and collapse of superhumps?

Geoff Stone, Josch Hambsch, Vihorlat observatory team
(Pavol A. Dubovsky, Tomas Medulka), Kyoto U. team, Tonny Vanmunster and
Crimean Astrophys. Obs. team reported further observations.

The object had reached the maximum magnitude of 14.1 mag on October 11
and turned to fading again. The current magnitude is 14.2 mag. The superhump
amplitude is also reduced after the maximum. The superhump amplitude is now
about 0.2 mag, and seems to be collapsing, although this is uncertain
because of
the sparseness of data. The PDM analysis for this 10 days suggests the
superhump period is 0.6969(2) d, this is longer than the previous one.

Further continuous observations are encouraged. The great activity of
this object
might have entered a final state.