Search Publications
Characterization of M dwarfs using optical mid-resolution spectra for exploration of small exoplanets
Wisniewski, John; Hirano, Teruyuki; Sato, Bun'ei +4 more
We present the optical spectra of 338 nearby M dwarfs, and compute their spectral types, effective temperatures (Teff), and radii. Our spectra were obtained using several optical spectrometers with spectral resolutions that range from 1200 to 10000. As many as 97% of the observed M-type dwarfs have a spectral type of M3-M6, with a typic…
Subaru Hyper Suprime-Cam revisits the large-scale environmental dependence on galaxy morphology over 360 deg2 at z = 0.3-0.6
Shimakawa, Rhythm; Tanaka, Masayuki; Tanaka, Takumi S. +1 more
This study investigates the role of large-scale environments on the fraction of spiral galaxies at z = 0.3-0.6 sliced to three redshift bins of Δz = 0.1. Here, we sample 276220 massive galaxies in a limited stellar mass of 5 × 1010 solar mass (~M*) over 360 deg2, as obtained from the Second Public Data Release of the Hyper Su…
Fundamental parameters for 30 faint open clusters with Gaia EDR3 based on the more reliable members
Ding, Xu; Yu, Xiao-Guang; Ji, Kai-Fan +4 more
An open cluster is an ideal region to study the evolution of stars. In this work, we use Gaia Early Data Release 3 (Gaia EDR3) to derive the fundamental parameters of 30 faint open clusters listed in the catalogue given by Cantat-Gaudin et al. (2018, A&A, 618, A93), but the G magnitude of all of the member stars of that catalogue is brighter t…
Cloud structures in M 17 SWex : Possible cloud-cloud collision
Sanhueza, Patricio; Kim, Kee-Tae; Nakamura, Fumitaka +11 more
Using wide-field 13CO (J = 1-0) data taken with the Nobeyama 45 m telescope, we investigate cloud structures of the infrared dark cloud complex in M 17 with Spectral Clustering for Interstellar Molecular Emission Segmentation. In total, we identified 118 clouds that include 11 large clouds with radii larger than 1 pc. The clouds are mai…
Energy estimation of high-energy particles associated with the SS 433/W 50 system through radio observation at 1.4 GHz
Sakemi, Haruka; Ohmura, Takumi; Machida, Mami +1 more
The radio nebula W 50 is a unique object interacting with the jets of the microquasar SS 433. The SS 433/W 50 system is a good target for investigating the energy of cosmic-ray particles accelerated by galactic jets. We report observations of the radio nebula W 50 conducted with the National Science Foundation's Karl G. Jansky Very Large Array in …
Detection of the hard X-ray non-thermal emission from Kepler's supernova remnant
Katsuda, Satoru; Terada, Yukikatsu; Bamba, Aya +1 more
We report the first robust detection of the hard X-ray emission in the 15-30 keV band from Kepler's supernova remnant with the silicon PIN-type semiconductor detector of the hard X-ray detector (HXD-PIN) onboard Suzaku. The detection significance is 7.17σ for the emission from Kepler's entire X-ray emitting region. The energy spectrum is found to …
Atomic carbon [C I](3P1-3P0) mapping of the nearby galaxy M 83
Seta, Masumichi; Salak, Dragan; Nakai, Naomasa +6 more
Atomic carbon (C I) has been proposed to be a global tracer of the molecular gas as a substitute for CO, however, its utility remains unproven. To evaluate the suitability of C I as the tracer, we performed [C I](3P1-3P0) [hereinafter [C I](1-0)] mapping observations of the northern part of the nearby sp…
A fundamental plane in X-ray binary activity of external galaxies
Ueda, Yoshihiro; Inoue, Yoshiyuki; Yabe, Kiyoto
We construct a new catalog of extragalactic X-ray binaries (XRBs) by matching the latest Chandra source catalog with local galaxy catalogs. Our XRB catalog contains 4430 XRBs hosted by 237 galaxies within ~130 Mpc. As XRBs dominate the X-ray activity in galaxies, the catalog enables us to study the correlations between the total X-ray luminosity o…
The spatial structure and dynamical state of the open cluster NGC 2112
Gao, Xinhua; Xu, ShouKun; Xue, Lei
This paper investigates the spatial structure and dynamical state of the old open cluster NGC 2112 based on likely cluster members from Gaia Early Data Release 3. Using the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm, we find 1193 likely cluster members down to G ~ 21 mag within a radius of 1.°5 from the cluster …
The C18O core mass function toward Orion A: Single-dish observations
Sanhueza, Patricio; Kataoka, Akimasa; Nakamura, Fumitaka +6 more
We have performed an unbiased dense core survey toward the Orion A Giant Molecular Cloud in the C18O (J = 1-0) emission line taken with the Nobeyama Radio Observatory (NRO) 45 m telescope. The effective angular resolution of the map is 26″, which corresponds to ~0.05 pc at a distance of 414 pc. By using the Herschel-Planck H2…