[vsnet-alert 23085] ASASSN-19ct: superoutburst of a likely AM CVn object

[Taichi Kato]

ASASSN-19ct: superoutburst of a likely AM CVn object

   Rod Stubbings has reported an outburst.

ASAS-SN data show that the object started to brighten
on Mar. 24.

https://asas-sn.osu.edu/light_curves/d02a682d-db78-4d07-96dc-a1df45a15215

  YYYYMMDD(UT)   mag  observer
  20190322.9685 <16.073g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190322.9697 <15.549g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190322.9709 <15.461g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190323.2545 <16.388g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190323.2558 <16.438g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190323.2795 <16.140g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190323.2807 <16.036g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190323.2819 <15.989g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190323.7723 <13.836g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190323.7748 <15.105g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.0782 15.962g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.0794 15.823g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.0806 15.962g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.2339 15.428g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.2352 15.325g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.2364 15.316g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.2376 15.524g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.2388 15.237g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.2401 15.206g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.7991 14.429g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.8003 14.433g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190324.8015 14.438g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.0731 15.125g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.0744 15.036g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.0756 15.047g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.2661 14.942g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.2673 14.929g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.2685 14.854g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.2697 14.886g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.2709 14.985g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.2722 14.740g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.475   140  (Rod Stubbings)
  20190325.8336 13.416g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.8349 13.419g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))
  20190325.8361 13.431g  (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017))

   The current outburst is most likely a superoutburst
(cf. vsnet-alert 22996), and it's a great opportunity
to record (a likely) AM CVn-type superhumps during
the early stage of an outburst.  Please use shorter
intervals of exposures than in ordinary CVs.