A5063868921- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Landslides and related hazards
- Metaheuristic Optimization Algorithms Research
- Metallurgy and Material Forming
- Cryospheric studies and observations
- Astrophysical Phenomena and Observations
- Advanced Multi-Objective Optimization Algorithms
- Gear and Bearing Dynamics Analysis
- Neural Networks and Applications
- Gamma-ray bursts and supernovae
- Cosmology and Gravitation Theories
- Soil and Unsaturated Flow
- Fluid Dynamics Simulations and Interactions
- Remote Sensing and LiDAR Applications
- Earthquake and Disaster Impact Studies
- Metal Forming Simulation Techniques
- Scientific Research and Discoveries
- Advanced Surface Polishing Techniques
- Coastal and Marine Dynamics
- Geotechnical Engineering and Underground Structures
- Metal Alloys Wear and Properties
- Mobile Agent-Based Network Management
Chiba University
2010-2024
Hokkaido University
2015-2024
Forestry and Forest Products Research Institute
2014-2024
Kobe University
2023-2024
Simon Fraser University
2023
Bridge University
2023
Kyoto Prefectural University
2023
Nagoya City University
1999-2021
Massachusetts Institute of Technology
2021
Science Council of Japan
2021
We perform cosmological hydrodynamic simulations to determine what extent galaxies lose their gas due photoheating from an ionizing background. find that the characteristic mass at which haloes on average have lost half of baryons is Mc ~ 6.5 x 10^9 Msun/h z = 0, corresponds a circular velocity 25 km/s. This significantly lower than filtering obtained by linear theory, often used in semianalytical models galaxy formation. demonstrate it temperature virial radius determines whether halo can...
We compare the results of thirteen cosmological gasdynamical codes used to simulate formation a galaxy in LCDM structure paradigm. The various runs differ their hydrodynamical treatment (SPH, moving-mesh and AMR) but share same initial conditions adopt latest published model cooling, star feedback. Despite common halo assembly history, we find large code-to-code variations stellar mass, size, morphology gas content at z=0, due mainly different implementations Compared with observation, most...
The physical properties and elemental abundances of the interstellar medium in galaxies during cosmic reionization are important for understanding role this process. We report Atacama Large Millimeter/submillimeter Array detection an oxygen emission line at a wavelength 88 micrometers from galaxy epoch about 700 million years after Big Bang. abundance is estimated one-tenth that Sun. nondetection far-infrared continuum indicates deficiency dust galaxy. A carbon 158 also not detected,...
We have performed hydrodynamic simulations of galaxy formation in a cold dark matter (ΛCDM) universe. followed halo, chosen to relatively quiet recent merger history, using different models for star and feedback. In all cases, we adopted multiphase description the interstellar medium modelled quiescent burst modes. explored two triggers starbursts—strong shocks high gas density—allowing possibility that stars may form with top-heavy initial mass function. find final morphology is extremely...
Abstract Transganglionic transport of HRP was used to study the patterns termination somatic afferent fibers innervating oral and facial structures within trigeminal nucleus caudalis upper cervical dorsal horn cat. In separate animals, superior alveolar, pterygopalatine, buccal, inferior lingual, frontal, corneal, zygomatic, infraorbital, mental, mylohyoid, auriculotemporal branches nerve were traced in this experiment. The organization primary afferents is not uniform across laminae at...
Abstract Transganglionic transport of horseradish peroxidase (HRP) was used to study the patterns termination somatic afferent fibers innervating oral and facial structures within principal nucleus (Vp), oralis (Vo), interpolaris (Vi). The primary trigeminal that innervate cavity supplied by pterygopalatine, superior alveolar, lingual, buccal, inferior alveolar branches, as well skin sunnlied frontal, corneal, zygomatic, infraorbital, auriculotemporal, mylohyoid, mental were traced in this...
We investigate the properties of satellite galaxies in cosmological N-body/SPH simulations galaxy formation Milky Way-sized haloes. Because their shallow potential wells, are very sensitive to heating processes which affect gas content. Their can therefore be used constrain nature feedback that regulate formation. In our simulations, we assume all energy produced by supernovae is as kinetic drive galactic winds. Several produce bright, disc-dominated galaxies. find wind models speed, v_w,...
We report on the detection of [CII] 157.7 $\mu$m emission from Lyman break galaxy (LBG) MACS0416_Y1 at z = 8.3113, by using Atacama Large Millimeter/submillimeter Array (ALMA). The luminosity ratio [OIII] 88 (from previous campaigns) to is 9.31 $\pm$ 2.6, indicative hard interstellar radiation fields and/or a low covering fraction photo-dissociation regions. cospatial 850 dust (90 rest-frame, campaigns), however peak does not agree with emission, suggesting that lines originate different...
Abstract We present the Atacama Large Millimeter/submillimeter Array detection of [O iii ] 88 μ m line and rest-frame 90 dust continuum emission in a Y -dropout Lyman break galaxy (LBG), MACS0416_Y1 lying behind Frontier Field cluster MACS J0416.1−2403. This confirms LBG with spectroscopic redshift z = 8.3118 ± 0.0003, making this object one farthest galaxies ever identified spectroscopically. The observed 850 flux density 137 26 Jy corresponds to de-lensed total infrared (IR) luminosity...
Abstract We present new ALMA observations and physical properties of a Lyman break galaxy at z = 7.15. Our target, B14-65666, has bright ultra-violet (UV) absolute magnitude, MUV ≈ −22.4, been spectroscopically identified in Lyα with small rest-frame equivalent width ≈4 Å. A previous Hubble Space TElescope (HST) image shown that the target is composed two spatially separated clumps UV. With ALMA, we have newly detected resolved [O iii] 88 μm, [C ii] 158 their underlying dust continuum...
We performed three-dimensional $N$-body/SPH simulations to study how mass resolution and other model parameters, such as the star-formation efficiency parameter, $C_*$ threshold density for star formation, $n_{\rm th}$ affect structures of galactic gaseous/stellar disk. employed $10^6$–$10^7$ particles resolve a cold ($T \lt$ 100 K) dense ($n_{\rm H} \gt$ cm$^{-3}$) phase well diffuse, hot phases. found that interstellar medium (ISM) distribution young stars were sensitive assumed values...
Abstract Two dimensional sloshing analysis has been carried out by the Lagrangian finite element method. For integration in time, velocity correction method with same interpolation functions for and pressure is successfully used. The treatment to pursue free surface position presented. comparison experiments shows extremely good agreement. It shown that large amplitude waves a container can be analyzed present
Seven cosmological hydrodynamic simulations of disk galaxy formation are analyzed to determine the alignment within dark matter halo and internal structure halo. We find that orientation outer halo, beyond ~0.1rvir, is unaffected by presence disk. In contrast, inner aligned such minor axis aligns with axis. The relative orientations these two regions uncorrelated. appears take place simultaneously through their joint evolution. lack connection between should be taken into account when...
We investigate the magnitude and internal alignment of angular momentum cold dark matter haloes in simulations with without baryons. analyse cumulative profiles hundreds thousands Millennium simulation a smaller, but higher resolution, simulation, total spanning 5 orders mass. For given mass, median specific increases as j(<r) proportional to r. The direction vector varies considerably radius: angle between inner (< 0.25 Rvir) vectors is about 25degr. To how baryons affect halo spin, we use...
We investigated the evolution of interacting disk galaxies using high-resolution $N$-body/SPH simulations, taking into account multiphase nature interstellar medium (ISM). In our a large-scale starburst occurred naturally at collision interface between two gas disks first encounter, resulting in formation star clusters. This is consistent with observations galaxies. The probability distribution function (PDF) density showed clear change during galaxy-galaxy encounter. compression appears as...
Abstract We investigate the metal enrichment of elliptical galaxies in framework hierarchical models galaxy formation. The semi-analytical model we use, which has been used to study intracluster medium (ICM) by Nagashima et al., includes effects flows gas and metals both into out processes due type Ia II supernovae. adopt a solar neighbourhood initial mass function (IMF) for star formation discs, but consider starbursts have either IMF or top-heavy IMF. find that α-element abundance...
In this paper, we present a new implementation of feedback due to active galactic nuclei (AGN) in cosmological simulations galaxy formation. We assume that fraction jet energy, which is generated by an AGN, transferred the surrounding gas as thermal energy. Combining theoretical model mass accretion on black holes with multiphase description star-forming gas, self-consistently follow evolution both galaxies and their central holes. The novelty our consider two distinct modes: standard...
We study the formation histories and present-day structure of satellite galaxies formed in a high resolution hydrodynamic simulation Milky Way-like galaxy. The simulated satellites span nearly 4 orders magnitude luminosity but have very similar mass within their inner 600 pc, ~ 3 10^7 M_solar, with little scatter. This result is agreement recent measurements for dwarf spheroidal (dSphs) Way by Strigari et al. In our simulations preferred scale arises naturally from effects early reionisation...
We investigate the evolution of angular momentum in simulations galaxy formation a cold dark matter universe. analyse two model galaxies generated N-body/hydrodynamic Okamoto et al. Starting from identical initial conditions, but using different assumptions for baryonic physics, one produced bulge-dominated and other disc-dominated galaxy. The main difference is treatment star feedback, both which were designed to be more efficient object. find that specific tracks halo very closely: grows...
The $r$-process-enhanced (RPE) stars provide fossil records of the assembly history Milky Way and nucleosynthesis heaviest elements. Observations by $R$-Process Alliance (RPA) others have confirmed that many RPE are associated with chemo-dynamically tagged groups, which likely came from accreted dwarf galaxies (MW). However, we do not know how formed. Here, present result a cosmological zoom-in simulation an MW-like galaxy $r$-process enrichment, performed highest resolution in both time...
Many techniques for rendering natural objects such as the sea, terrains, and trees have been developed; they are indispensable flight simulators. In this paper, road surfaces under various conditions discussed. Rendering is quite useful evaluation of driving safety, it will play an important part in development drive Light sources with high intensity often disturb drivers especially wet surface conditions.This paper proposes two models, a reflection model taking into account weather...
We investigate the properties of satellite galaxies formed in N-body/SPH simulations galaxy formation $Λ$CDM cosmology. The include main physical effects thought to be important and, several cases, produce realistic spiral discs. In total, a sample 9 luminosity comparable Milky Way was obtained. At magnitudes brighter than resolution limit, $M_V=-12$, function is excellent agreement with data for Local Group. radial number density profile model satellites, as well their gas fractions also...