Detection of the supercycle in V4140 Sagittarii: First eclipsing ER Ursae Majoris-like object. (4th May 2018)

• Record Type: Journal Article
• Authors: Kato, Taichi; Hambsch, Franz-Josef; Cook, Lewis M
• Is Part Of: Publications of the Astronomical Society of Japan. Volume 70:Number 3(2018:Jun.)
• Publication Date: 2018-05-04
• Subjects: accretion, accretion disks -- stars: dwarf novae -- stars: individual (V4140 Sagittarii) -- stars: novae, cataclysmic variables; Astronomy -- Periodicals; 520.5
• DOI: 10.1093/pasj/psy049
• Languages: English
• ISSNs: 0004-6264

Abstract

Abstract: We observed the deeply eclipsing SU UMa-type dwarf nova V4140 Sgr and established the very short supercycle of 69.7(3) d. There were several short outbursts between superoutbursts. These values, together with the short orbital period (0.06143 d), were similar to, but not as extreme as, those of ER UMa-type dwarf novae. The object is thus the first, long sought, eclipsing ER UMa-like object. This ER UMa-like nature can naturally explain the high (apparent) quiescent viscosity and unusual temperature profile in quiescence, which were claimed observational features against the thermal–tidal instability model. The apparently unusual outburst behavior can be reasonably explained by a combination of this ER UMa-like nature and the high orbital inclination, and there is no need to introduce mass transfer bursts from its donor star.