PNV J00444033+4113068: Early superhumps with 0.7 mag amplitude and non-red color

• DOI: 10.1093/pasj/psac068
• Publication Date: 2022-09-16T11:38:58Z
• Authors: Yusuke Tampo; Keisuke Isogai; Naoto Kojiguchi; Makoto Uemura; Taichi Kato; Tamás Tordai; Tonny Vanmunster; Hiroshi Itoh; Pavol A Dubovsky; Tomáš Medulka; Yasuo Sano; Franz-Josef Hambsch; Kenta Taguchi; Hiroyuki Maehara; Junpei Ito; Daisaku Nogami
• Keywords: Dwarf nova; Accretion disc; Eclipse; Bright spot

In the first days of WZ Sge-type dwarf nova (DN) outbursts, 2:1 resonance induces a spiral arm structure in accretion disk, which is observed as early superhumps optical light curves. This paper reports our observations an eclipsing DN PNV J00444033+4113068 during its 2021 superoutburst with 3.8m Seimei telescope and through VSNET collaboration. The eclipse analysis gave orbital period 0.055425534(1) d. Our confirmed amplitude 0.7 mag, largest among known DNe. More interestingly, became reddest around their secondary minimum, whereas other DNe show color superhump maximum. spectrum peak outburst showed double-peaked emission lines He II 4686\AA~ H$\alpha$ separation $\ge 700$ km/s, supporting very high-inclination system. With mapping, unique profile are successfully reproduced by disk vertically extended double structure. Therefore, large behavior can be explained model along