activity
20242026
collaborators

6 papers

astro-ph.HE2026

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…

astro-ph.SR2026

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…

astro-ph.SR2025

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…

astro-ph.SR2025

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…

astro-ph.SR2025

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…

astro-ph.SR2024

Smart Kanata: A Framework for Autonomous Decision Making in Rapid Follow-up Observations of Cataclysmic Variables

Makoto Uemura, Yuzuki Koga, Ryosuke Sazaki +11

Studying the early stages of transient events provides crucial information about the fundamental physical processes in cataclysmic variables (CVs). However, determining an appropri…