activity
20242026
collaborators

7 papers

astro-ph.GA2026

Interplay of Compaction, Quenching, and Black Hole Growth in the Most Massive Galaxies since : Insights from JWST and Chandra Data

Novan Saputra Haryana, Masayuki Akiyama, Abdurro'uf +16

The buildup of dense stellar cores is expected to mark an important transition in the star-formation and black-hole growth of massive galaxies. Using spatially resolved spectral en…

astro-ph.GA2026

A z ~ 0.4 Galaxy Reflecting the high-redshift Little Red Dots: An Extended Starburst with an Overmassive Black Hole

Xiaoyang Chen, Kohei Ichikawa, Masayuki Akiyama +10

One of the most remarkable discoveries of JWST is a population of compact, red sources at z > 4, commonly referred to as Little Red Dots (LRDs). Spectroscopic identifications repor…

astro-ph.GA2025

Discovery of an X-ray Luminous Radio-Loud Quasar at : A Possible Transitional Super-Eddington Phase

Sakiko Obuchi, Kohei Ichikawa, Satoshi Yamada +11

We report the multiwavelength properties of eFEDS J084222.9+001000 (hereafter ID830), a quasar at , identified as the most X-ray luminous radio-loud quasar in the eROSITA…

astro-ph.GA2025

Stellar Mass Assembly History of Massive Quiescent Galaxies since : Insights from Spatially Resolved SED Fitting with JWST Data

Novan Saputra Haryana, Masayuki Akiyama, Abdurro'uf +12

Massive quiescent galaxies at high redshift show significantly more compact morphology than their local counterparts. To examine their internal structure across a wide redshift ran…

astro-ph.GA2024

Implication of a galaxy-scale negative feedback by one of the most powerful multi-phase outflows in a hyper-luminous infrared galaxy at the intermediate redshift

Xiaoyang Chen, Masayuki Akiyama, Kohei Ichikawa +12

Powerful, galactic outflows driven by Active Galactic Nuclei (AGNs) are commonly considered as a main mechanism to regulate star formation in massive galaxies. Ultra- and hyper-lum…

astro-ph.HE2024

A systematic search for rapid transients in the Subaru HSC-SSP transient survey

Seiji Toshikage, Masaomi Tanaka, Naoki Yasuda +9

Recent high-cadence transient surveys have discovered rapid transients whose light curve timescales are shorter than those of typical supernovae. In this paper, we present a system…