40 citations · 245 across the 17 of their papers we have counts for
17 papers
Formation of Parallel Stellar Streams through Encounters with Dark Matter Subhalos and Intermediate-Mass Black Holes
Yuka Kaneda, Masao Mori, Yohei Miki +2
Dark matter subhalos and intermediate-mass black holes wandering in the Milky Way and the Andromeda galaxy are difficult to directly detect through electromagnetic observations, ye…
Galactic Archaeology with the Subaru `Ōnohi`ula Prime Focus Spectrograph Strategic Program
Masashi Chiba, Rosemary F. G. Wyse, Evan N. Kirby +48
The recently commissioned Subaru `Ōnohi`ula Prime Focus Spectrograph (PFS) will obtain spectra from nearly 2,400 fibers that cover 1.24 square degrees. The 360 night Subaru Strateg…
Simultaneous Formation of the Andromeda Giant Southern Stream and the Substructures in the Andromeda Halo
Misa Yamaguchi, Masao Mori, Takanobu Kirihara +4
We investigate a minor merger event in M31 that simultaneously forms the Andromeda Giant Southern Stream (AGSS), Eastern Extent (EE), North-Eastern Shelf (NES), and Western Shel (W…
Destruction of the central black hole gas reservoir through head-on galaxy collisions
Yohei Miki, Masao Mori, Toshihiro Kawaguchi
A massive black hole exists in almost every galaxy. They occasionally radiate a vast amount of light by releasing gravitational energy of accreting gas, with a cumulative active pe…
Cusp-to-core transition in low-mass dwarf galaxies induced by dynamical heating of cold dark matter by primordial black holes
Pierre Boldrini, Yohei Miki, Alexander Y. Wagner +3
We performed a series of high-resolution -body simulations to examine whether dark matter candidates in the form of primordial black holes (PBHs) can solve the cusp-core problem…
Gravitational octree code performance evaluation on Volta GPU
Yohei Miki
In this study, the gravitational octree code originally optimized for the Fermi, Kepler, and Maxwell GPU architectures is adapted to the Volta architecture. The Volta architecture…
MAGI: many-component galaxy initialiser
Yohei Miki, Masayuki Umemura
Providing initial conditions is an essential procedure for numerical simulations of galaxies. The initial conditions for idealised individual galaxies in -body simulations shoul…
Stellar Stream and Halo Structure in the Andromeda Galaxy From a Subaru/Hyper Suprime-Cam Survey
Yutaka Komiyama, Masashi Chiba, Mikito Tanaka +13
We present wide and deep photometry of the northwest part of the halo of the Andromeda galaxy (M31) using Hyper Suprime-Cam on the Subaru Telescope. The survey covers 9.2 deg…
The nature of the progenitor of the M31 North-western stream: globular clusters as milestones of its orbit
Takanobu Kirihara, Yohei Miki, Masao Mori
We examine the nature, possible orbits and physical properties of the progenitor of the North-western stellar stream (NWS) in the halo of the Andromeda galaxy (M31). The progenitor…
GOTHIC: Gravitational oct-tree code accelerated by hierarchical time step controlling
Yohei Miki, Masayuki Umemura
The tree method is a widely implemented algorithm for collisionless -body simulations in astrophysics well suited for GPU(s). Adopting hierarchical time stepping can accelerate…
Collision tomography: Physical properties of possible progenitors of the Andromeda stellar stream
Yohei Miki, Masao Mori, R. Michael Rich
To unveil a progenitor of the Andromeda Giant Stellar Stream, we investigate the interaction between an accreting satellite galaxy and the Andromeda Galaxy using an -body simula…
Formation of the Andromeda Giant Stream: Asymmetric Structure and Disc Progenitor
Takanobu Kirihara, Yohei Miki, Masao Mori +2
We focus on the evidence of a past minor merger discovered in the halo of the Andromeda galaxy (M31). Previous N-body studies have enjoyed moderate success in producing the observe…
Puzzling Outer-Density Profile of the Dark Matter Halo in the Andromeda Galaxy
Takanobu Kirihara, Yohei Miki, Masao Mori
The cold dark matter (CDM) cosmology, which is the standard theory of the structure formation in the universe, predicts that the outer density profile of dark matter halos decrease…
Relics of Galaxy Merging: Observational Predictions for a Wandering Massive Black Hole and Accompanying Star Cluster in the Halo of M31
Toshihiro Kawaguchi, Yuriko Saito, Yohei Miki +1
Galaxies and massive black holes (BHs) presumably grow via galactic merging events and subsequent BH coalescence. As a case study, we investigate the merging event between the Andr…
Hunting A Wandering Supermassive Black Hole in M31 Halo -- Hermitage of Black Hole
Yohei Miki, Masao Mori, Toshihiro Kawaguchi +1
In the hierarchical structure formation scenario, galaxies enlarge through multiple merging events with less massive galaxies. In addition, the Magorrian relation indicates that al…
Resolving the outer density profile of dark matter halo in Andromeda galaxy
Takanobu Kirihara, Yohei Miki, Masao Mori
Large-scale faint structure detected by the recent observations in the halo of the Andromeda galaxy (M31) provides an attractive window to explore the structure of outer cold dark…
Astrophysical Particle Simulations on Heterogeneous CPU-GPU Systems
Naohito Nakasato, Go Ogiya, Yohei Miki +2
A heterogeneous CPU-GPU node is getting popular in HPC clusters. We need to rethink algorithms and optimization techniques for such system depending on the relative performance of…