MGAB-V859 and ZTF18abgjsdg: ER UMa-type dwarf novae showing standstills [SSA]

http://arxiv.org/abs/2107.14400


Using Public Data Release of Zwicky Transient Facility observations, we found that MGAB-V859 and ZTF18abgjsdg are dwarf novae and show both ER UMa-type and Z Cam-type states. There had been only two dwarf novae showing similar transitions between the ER UMa-type and Z Cam-type states. MGAB-V859 showed both a transition from the ER UMa-type state to a long standstill in 2019 and a Z Cam-type state in 2020. During the standstill in 2020, this object faded twice and showed dwarf nova-type variations. ZTF18abgjsdg usually showed ER UMa-type behavior but standstills were seen in 2018 and 2019. The supercycles of these objects during the typical ER UMa-type phase were 55 d and 58 d, respectively. These objects provide additional evidence that some ER UMa stars indeed bridge between dwarf nova and novalike states as proposed in Kato et al. (2016).

Read this paper on arXiv…

T. Kato and N. Kojiguchi
Mon, 2 Aug 21
9/82

Comments: 6 pages, 5 figures, to appear in VSOLJ Variable Star Bulletin