5 papers
Multi-band optical photometric variability of the blazar OJ 287 from 2015 to 2025
Alok C. Gupta, Karan Dogra, Mark Kidger +101
We present the most densely sampled multi-band optical photometric observations of the peculiar BL Lacertae object OJ 287 from 2015 to 2025 with a focus on its optical activity on…
A probable inside-out dwarf nova outburst from the period bouncer candidate ASASSN-25dc
Yusuke Tampo, Naoto Kojiguchi, Mariko Kimura +13
We report optical time-resolved photometric observations of a newly-discovered outbursting system, ASASSN-25dc. Its 8-mag amplitude, 40-day duration, 1-mag dip in the outburst plat…
TESS and ground-based observations of WZ Sge-type dwarf novae in outburst
Y. Tampo, N. Kojiguchi, K. Isogai +30
Dwarf nova (DN) superoutbursts are accompanied by superhumps, which change their periods and profiles over a superoutburst. We present the TESS and ground-based observations of nin…
ASASSN-24hd; a dwarf nova bridging WZ Sge-type and SU UMa-type superoutbursts
Yusuke Tampo, Naoto Kojiguchi, Taichi Kato +9
WZ Sge-type dwarf novae (DNe) form a subclass in cataclysmic variables, characterized by short-period variations called superhumps during an outburst. Here we present optical groun…
Spectral evolution of the narrow emission line components in optical during the 2022 nova eruption of U Scorpii
Katsuki Muraoka, Naoto Kojiguchi, Junpei Ito +20
There remains debate over whether the accretion disk survives or is entirely disrupted after the nova eruption. In our previous paper, Muraoka et al. (2024, PASJ, 76, 293) have pho…