%0 Journal Article
%T Observation of ER UMa Stars
%A Taichi Kato
%A Daisaku Nogami
%A Hajime Baba
%A Seiji Masuda
%A Katsura Matsumoto
%A Chatief Kunjaya
%J Physics
%D 2013
%I arXiv
%X ER UMa stars are a recently recognized small subgroup of SU UMa-type dwarf novae, which are characterized by the extremely high outburst frequency and short (19--48 d) supercycles. From the current thermal-tidal disk instability scheme, they are considered to be high mass-transfer SU UMa-type dwarf novae, and comprise a link to "permanent superhumpers" below the period gap. They do not only provide an opportunity to test the applicability of thermal-tidal instability model but also pose problems on the origin of high mass-transfer in short orbital-period cataclysmic variables. A historical review of this subgroup and recent topics of ER UMa stars, the unique pattern of superhump evolution and the "helium ER UMa analog" (CR Boo), are also discussed.
%U http://arxiv.org/abs/1301.3202v1