Search Publications
Discovery of a hyperluminous quasar at z = 1.62 with Eddington ratio >3 in the eFEDS field confirmed by KOOLS-IFU on Seimei Telescope
Imanishi, Masatoshi; Ueda, Yoshihiro; Toba, Yoshiki +17 more
We report the discovery of a hyperluminous type 1 quasar (eFEDS J082826.9-013911; eFEDS J0828-0139) at
Processing of hydrocarbon dust in star-forming galaxies revealed with AKARI
Oyabu, Shinki; Kaneda, Hidehiro; Murata, Katsuhiro L. +5 more
Hydrocarbon dust is one of the dominant components of interstellar dust, which mainly consists of polycyclic aromatic hydrocarbons and aliphatic hydrocarbons. While hydrocarbon dust is thought to be processed in interstellar radiation fields or shocks, detailed processing mechanisms are not completely understood yet. We investigate the processing …
Near-ultraviolet radiation toward molecular cloud N4 in W 50/SS 433: Evidence for direct interaction of the jet with molecular cloud
Takeuchi, Tsutomu T.; Yamamoto, Hiroaki; Ishikawa, Tatsumi
We compared the molecular clouds in the western part of SS 433 with near-ultraviolet radiation data obtained from GALEX. Near-ultraviolet radiation is prominently confirmed toward only N4, while no near-ultraviolet radiation is detected toward N1, N2, or N3. The radiative region of near-ultraviolet radiation is nearly the same as the CO-emitting r…
Investigation of mid-infrared long-term variability of dusty AGB stars using multi-epoch scan data of AKARI and WISE
Takita, Satoshi; Ita, Yoshifusa; Tachibana, Kengo +5 more
Asymptotic giant branch (AGB) stars are one of the main sources of dust in the Universe. They form and supply dust triggered by stellar pulsations, but the details of the mechanism are still unknown. Among all AGB stars, dusty AGB stars are the most important in terms of dust supply because they contain the star with a high mass-loss rate. To inve…
Physical properties of the molecular cloud, N4, in SS 433: Evidence for an interaction of molecular cloud with the jet from SS 433
Nakanishi, Hiroyuki; Yamamoto, Hiroaki; Imai, Hiroshi +3 more
We conducted observations and analyses of the molecular cloud, N4, which is located at ~40 pc from SS 433 and the same line of sight as that of the radio shell, in 12CO(J = 1-0), 12CO(J = 3-2), 13CO(J = 3-2), and grand-state OH emissions. N4 has a strong gradient of the integrated intensity of 12CO(J = 1…
CO observations of the molecular gas in the Galactic H II region Sh2-48: Evidence for cloud-cloud collision as a trigger of high-mass star formation
Kuno, Nario; Tachihara, Kengo; Fukui, Yasuo +15 more
Sh2-48 is a Galactic H II region, 3.8 kpc distant, with an O9.5-type star identified at its center. As a part of the FOREST Unbiased Galactic plane Imaging survey using the Nobeyama 45 m telescope (FUGIN) project, we obtained a CO J = 1-0 data set for a large area of Sh2-48 at a spatial resolution of 21″ (∼0.4 pc), and used it to find a molecular …
CO observations toward the isolated mid-infrared bubble S44: External triggering of O-star formation by a cloud-cloud collision
Tachihara, Kengo; Fukui, Yasuo; Sano, Hidetoshi +11 more
We have performed a multi-wavelength study of the mid-infrared bubble S44 to investigate the origin of isolated high-mass star(s) and the star-formation process around the bubble formed by the H II region. We report on the results of new CO observations (12CO, 13CO J = 1-0, and 12CO J = 3-2) toward the isolated bub…
The nature of bright C-complex asteroids
Hasegawa, Sunao; Usui, Fumihiko; Kuroda, Daisuke +1 more
Most C-complex asteroids have albedo values less than 0.1, but there are some high-albedo (bright) C-complex asteroids with albedo values exceeding 0.1. To reveal the nature and origin of bright C-complex asteroids, we conducted spectroscopic observations of the asteroids at visible and near-infrared wavelengths. As a result, the bright B-, C-, an…
Dust dissipation timescales in the intermediate and outer regions of protoplanetary disks
Nakagawa, Takao; Kwon, Jungmi; Takita, Satoshi +2 more
Dust and gas in protoplanetary disks dissipate as central stars evolve. In order to estimate the dust dissipation timescales in the protoplanetary disks, we stacked the WISE 12 and 22, and the AKARI 90 µm survey images of known T Tauri stars and derived the average fluxes, well below the survey flux limit in the 90 µm band. We classifi…
A systematic study of Galactic infrared bubbles along the Galactic plane with AKARI and Herschel. II. Spatial distributions of dust components around the bubbles
Oyabu, Shinki; Kaneda, Hidehiro; Ishihara, Daisuke +7 more
Galactic infrared (IR) bubbles, which can be seen as shell-like structures at mid-IR wavelengths, are known to possess massive stars within their shell boundaries. In our previous study (Hanaoka, 2019, PASJ, 71, 6), we expanded the research area to the whole Galactic plane (0° ≤ l ≤ 360°, |b| ≤ 5°) and studied systematic differences in the shell m…