Search Publications
X-ray properties of high-richness CAMIRA clusters in the Hyper Suprime-Cam Subaru Strategic Program field
Oguri, Masamune; Fujimoto, Ryuichi; Okabe, Nobuhiro +13 more
We present the first results of a pilot X-ray study of 37 rich galaxy clusters at 0.1 < z < 1.1 in the Hyper Suprime-Cam Subaru Strategic Program field. Diffuse X-ray emissions from these clusters were serendipitously detected in the XMM-Newton fields of view. We systematically analyze X-ray images of 37 clusters and emission spectra of a su…
BC Cassiopeiae: First detection of IW Andromedae-type phenomenon among post-eruption novae
Kato, Taichi; Kojiguchi, Naoto
IW And-type dwarf novae are a recently recognized group of cataclysmic variables which are characterized by a sequence of brightening from a standstill-like phase with damping oscillations often followed by a deep dip. We found that the supposed classical nova BC Cas which erupted in 1929 experienced a state of an IW And-type dwarf nova in 2018, 8…
HCN 3-2 survey towards a sample of local galaxies
Fang, Min; Li, Shanghuo; Wang, Junzhi +4 more
We present observations of HCN 3-2 emissions towards 37 local galaxies using the 10 m Submillimeter Telescope. HCN 3-2 emission is detected in 23 galaxies. The correlation of infrared luminosity (LIR) and the luminosity of HCN 3-2 line emission measured in our sample is fitted with a slope of 1.11 and correlation coefficient of 0.91, wh…
Gaia DR2 data and the evolutionary status of eight high-velocity hot post-AGB candidates
Matsuno, Tadafumi; Aoki, Wako; Parthasarathy, Mudumba
From Gaia DR2 data of eight high-velocity hot post-AGB candidates, LS 3593, LSE 148, LS 5107, HD 172324, HD 214539, LS IV -12 111, LS III +52 24, and LS 3099, we found that six of them have accurate parallaxes which made it possible to derive their distances, absolute visual magnitudes (MV) and luminosity (log L/L⊙). All the …
Discovery of radio jets in the Phoenix galaxy cluster center
Kohno, Kotaro; Oguri, Masamune; Kawabe, Ryohei +6 more
We report the results of the Australia Telescope Compact Array (ATCA) 15 mm observation of the Phoenix galaxy cluster possessing an extreme star-burst brightest cluster galaxy (BCG) at the cluster center. We spatially resolved radio emission around the BCG, and found diffuse bipolar and bar-shape structures extending from the active galactic nucle…
Detection of tidal tails around the open cluster M 67 using principal component analysis
Gao, Xinhua
In this paper we present an investigation of tidal tails around the old open cluster M 67 using Gaia-DR2. We identify likely extra-tidal stars around M 67 using principal component analysis (PCA) and a Gaussian mixture model (GMM). We find 1618 stars closely related to M 67, 85 of which are likely extra-tidal stars. We find clear evidence for the …
First detection of X-ray line emission from Type IIn supernova 1978K with XMM-Newton's RGS
Katsuda, Satoru; Takahashi, Koh; Yoshida, Takashi +2 more
We report on robust measurements of elemental abundances of the Type IIn supernova SN 1978K, based on the high-resolution X-ray spectrum obtained with the Reflection Grating Spectrometer (RGS) onboard XMM-Newton. The RGS clearly resolves a number of emission lines, including N Ly $\alpha$ , O Ly $\alpha$ , O Ly $\beta$ , Fe xvii, Fe xviii, Ne He $…
Astrometry and infrared observations of the Mira variable stars AP Lyncis, V837 Herculis, and BX Camelopardalis: Implications for the period-luminosity relation of the Milky Way
Fujimoto, Masayuki Y.; Nakagawa, Akiharu; Nagayama, Takahiro +6 more
AP Lyn and V837 Her are long-period Mira variable stars in the Milky Way. We performed VLBI Exploration of Radio Astrometry (VERA) phase-referenced observations towards H2O masers associated with AP Lyn and V837 Her. The annual parallaxes of AP Lyn and V837 Her were obtained to be 2.008 ± 0.038 mas and 1.090 ± 0.014 mas, corresponding t…
Discovery of a transient X-ray source Suzaku J1305-4930 in NGC 4945
Yoneyama, Tomokage; Hayashida, Kiyoshi; Matsumoto, Hironori +3 more
We report the serendipitous discovery of a transient X-ray source, Suzaku J1305-4930, ∼3 kpc southwest of the nucleus of the Seyfert 2 galaxy NGC 4945. Among the seven Suzaku observations of NGC 4945 from 2005 to 2011, Suzaku J1305-4930 was detected four times in July and August in 2010. The X-ray spectra are better approximated with a multi-color…
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…