We present results from a new cosmological hydrodynamics simulation campaign of protocluster (PC) regions, FOREVER22: FORmation and EVolution of galaxies in Extremely overdense Regions motivated by SSA22. The simulations cover a wide range of cosmolo...
We use the results of relativistic hydrodynamic simulations of jet- interstellar medium (ISM) interactions in a galaxy with a radio- loud AGN to quantify the extent of ionization in the central few kpcs of the gaseous galactic disc. We perform post-p...
We study the formation of star clusters in molecular clouds by performing three-dimensional radiation hydrodynamics simulations with far ultraviolet (FUV; 6 eV≦hν≦13.6 eV) and extreme ultraviolet (EUV; hν≧13.6 eV) radiative feedback. We find that the...
We have analyzed the data from a large-scale CO survey toward the northern region of the Small Magellanic Cloud (SMC) obtained with the Atacama Compact Array (ACA) stand-alone mode of ALMA. The primary aim of this study is to comprehensively understa...
We study the ionization and excitation structure of the interstellar medium in the late-stage gas-rich galaxy merger NGC 6240 using a suite of emission-line maps at ~25 pc resolution from the Hubble Space Telescope, Keck/NIRC2 with Adaptive Optics, a...
We apply a turbulence-regulated model of star formation to calculate the star formation rate (SFR) of dense star-forming clouds in simulations of jet-interstellar medium (ISM) interactions. The method isolates individual clumps and accounts for the i...
MeerKAT radio continuum and XMM-Newton X-ray images have recently revealed a spectacular bipolar channel at the Galactic Center that spans several degrees (~0.5 kpc). An intermittent jet likely formed this channel and is consistent with earlier evide...
We perform high-resolution cosmological hydrodynamic simulations to study the formation of the first galaxies that reach the masses of 108-9 h-1 M⊙ at z = 9. The resolution of the simulations is high enough to resolve minihaloes and allow us to succe...
The member stars in globular cluster M15 show a substantial spread in the abundances of r-process elements. We argue that a rare and prolific r-process event enriched the natal cloud of M15 in an inhomogeneous manner. To critically examine the possib...
Relativistic jets can interact with the ambient gas distribution of the host galaxy, before breaking out to larger scales. In the past decade, several studies have simulated jet-driven outflows to understand how they affect the nearby environment, an...
We study the fragmentation of collisional ring galaxies (CRGs) using a linear perturbation analysis that computes the physical conditions of gravitational instability, as determined by the balance of self-gravity of the ring against pressure and Cori...
We present the optical and infrared properties of 39 extremely radio- loud galaxies discovered by cross-matching the Subaru/Hyper Suprime-Cam (HSC) deep optical imaging survey and VLA/FIRST 1.4 GHz radio survey. The recent Subaru/HSC strategic survey...
Growth of the black holes (BHs) from the seeds to supermassive BHs (SMBHs, ~109M⊙) is not understood, but the mass accretion must have played an important role. We performed 2D radiation hydrodynamics simulations of line-driven disc winds considering...
It has long been suspected that powerful radio sources may lower the efficiency with which stars form from the molecular gas in their host galaxy, however so far, alternative mechanisms, in particular related to the stellar mass distribution in the m...
By performing 3D radiation hydrodynamics simulations, we study the formation of young massive star clusters (YMCs; M* > 104 M⊙) in clouds with the surface density ranging from Σcl = 80 to 3200 M⊙ pc-2. We find that photoionization feedback suppresses...
Galactic winds are crucial to the cosmic cycle of matter, transporting material out of the dense regions of galaxies. Observations show the coexistence of different temperature phases in such winds, which is not easy to explain. We present a set of 3...
We investigate dynamical states of grand-design spiral arms in three local galaxies: M51, NGC 3627, and NGC 628. Based on linear perturbation analysis considering multiple components in the galaxies, we compute instability parameters of the spiral ar...
With unprecedented angular resolution, the Event Horizon Telescope (EHT) has opened a new era of black hole studies. We have previously calculated the expected polarization images of M 87* with EHT observations in mind. There, we demonstrated that ci...
We study the production of barium (Ba) and strontium (Sr) in ultrafaint dwarf (UFDs) galaxies. Both r- and s- processes produce these elements, and one can infer the contribution of the r-process from the characteristic r-process abundance pattern, w...
UltraFast Outflows (UFOs) are observed in some active galactic nuclei (AGN), with blueshifted and highly ionized Fe-K absorption features. AGN typically have an ultraviolet (UV-) bright accretion flow, so UV line driving is an obvious candidate for l...
We present element abundance ratios and ionizing radiation of local young low-mass (~106 M⊙) extremely metal-poor galaxies (EMPGs) with a 2% solar oxygen abundance (O/H)⊙ and a high specific star formation rate (sSFR ~ 300 Gyr-1) and other (extremely...
Planetesimals are believed to be formed by the coagulation of dust grains in the protoplanetary disk turbulence. However, the bouncing and fragmentation barriers have not been completely solved, particularly for silicate dust. To circumvent these bar...
We present results from a new cosmological hydrodynamics simulation campaign of protocluster (PC) regions, FOREVER22: FORmation and EVolution of galaxies in Extremely overdense Regions motivated by SSA22. The simulations cover a wide range of cosmolo...
令和4年 1月 Monthly Notices of the Royal Astronomical Society
We use the results of relativistic hydrodynamic simulations of jet- interstellar medium (ISM) interactions in a galaxy with a radio- loud AGN to quantify the extent of ionization in the central few kpcs of the gaseous galactic disc. We perform post-p...
令和4年 1月 Monthly Notices of the Royal Astronomical Society
We study the formation of star clusters in molecular clouds by performing three-dimensional radiation hydrodynamics simulations with far ultraviolet (FUV; 6 eV≦hν≦13.6 eV) and extreme ultraviolet (EUV; hν≧13.6 eV) radiative feedback. We find that the...
令和4年 1月 Monthly Notices of the Royal Astronomical Society
We have analyzed the data from a large-scale CO survey toward the northern region of the Small Magellanic Cloud (SMC) obtained with the Atacama Compact Array (ACA) stand-alone mode of ALMA. The primary aim of this study is to comprehensively understa...
令和3年 12月 The Astrophysical Journal
We study the ionization and excitation structure of the interstellar medium in the late-stage gas-rich galaxy merger NGC 6240 using a suite of emission-line maps at ~25 pc resolution from the Hubble Space Telescope, Keck/NIRC2 with Adaptive Optics, a...
令和3年 12月 The Astrophysical Journal
We apply a turbulence-regulated model of star formation to calculate the star formation rate (SFR) of dense star-forming clouds in simulations of jet-interstellar medium (ISM) interactions. The method isolates individual clumps and accounts for the i...
令和3年 12月 Monthly Notices of the Royal Astronomical Society
MeerKAT radio continuum and XMM-Newton X-ray images have recently revealed a spectacular bipolar channel at the Galactic Center that spans several degrees (~0.5 kpc). An intermittent jet likely formed this channel and is consistent with earlier evide...
令和3年 12月 The Astrophysical Journal
We perform high-resolution cosmological hydrodynamic simulations to study the formation of the first galaxies that reach the masses of 108-9 h-1 M⊙ at z = 9. The resolution of the simulations is high enough to resolve minihaloes and allow us to succe...
令和3年 12月 Monthly Notices of the Royal Astronomical Society
The member stars in globular cluster M15 show a substantial spread in the abundances of r-process elements. We argue that a rare and prolific r-process event enriched the natal cloud of M15 in an inhomogeneous manner. To critically examine the possib...
令和3年 11月 The Astrophysical Journal Letters
Relativistic jets can interact with the ambient gas distribution of the host galaxy, before breaking out to larger scales. In the past decade, several studies have simulated jet-driven outflows to understand how they affect the nearby environment, an...
令和3年 11月 Astronomische Nachrichten
We study the fragmentation of collisional ring galaxies (CRGs) using a linear perturbation analysis that computes the physical conditions of gravitational instability, as determined by the balance of self-gravity of the ring against pressure and Cori...
令和3年 11月 Monthly Notices of the Royal Astronomical Society
We present the optical and infrared properties of 39 extremely radio- loud galaxies discovered by cross-matching the Subaru/Hyper Suprime-Cam (HSC) deep optical imaging survey and VLA/FIRST 1.4 GHz radio survey. The recent Subaru/HSC strategic survey...
令和3年 11月 The Astrophysical Journal
Growth of the black holes (BHs) from the seeds to supermassive BHs (SMBHs, ~109M⊙) is not understood, but the mass accretion must have played an important role. We performed 2D radiation hydrodynamics simulations of line-driven disc winds considering...
令和3年 10月 Monthly Notices of the Royal Astronomical Society
It has long been suspected that powerful radio sources may lower the efficiency with which stars form from the molecular gas in their host galaxy, however so far, alternative mechanisms, in particular related to the stellar mass distribution in the m...
令和3年 10月 Astronomy & Astrophysics
By performing 3D radiation hydrodynamics simulations, we study the formation of young massive star clusters (YMCs; M* > 104 M⊙) in clouds with the surface density ranging from Σcl = 80 to 3200 M⊙ pc-2. We find that photoionization feedback suppresses...
令和3年 10月 Monthly Notices of the Royal Astronomical Society
Galactic winds are crucial to the cosmic cycle of matter, transporting material out of the dense regions of galaxies. Observations show the coexistence of different temperature phases in such winds, which is not easy to explain. We present a set of 3...
令和3年 10月 Monthly Notices of the Royal Astronomical Society
We investigate dynamical states of grand-design spiral arms in three local galaxies: M51, NGC 3627, and NGC 628. Based on linear perturbation analysis considering multiple components in the galaxies, we compute instability parameters of the spiral ar...
令和3年 9月 Monthly Notices of the Royal Astronomical Society
With unprecedented angular resolution, the Event Horizon Telescope (EHT) has opened a new era of black hole studies. We have previously calculated the expected polarization images of M 87* with EHT observations in mind. There, we demonstrated that ci...
令和3年 8月 Publications of the Astronomical Society of Japan
We study the production of barium (Ba) and strontium (Sr) in ultrafaint dwarf (UFDs) galaxies. Both r- and s- processes produce these elements, and one can infer the contribution of the r-process from the characteristic r-process abundance pattern, w...
令和3年 8月 Monthly Notices of the Royal Astronomical Society
UltraFast Outflows (UFOs) are observed in some active galactic nuclei (AGN), with blueshifted and highly ionized Fe-K absorption features. AGN typically have an ultraviolet (UV-) bright accretion flow, so UV line driving is an obvious candidate for l...
令和3年 5月 Monthly Notices of the Royal Astronomical Society
We present element abundance ratios and ionizing radiation of local young low-mass (~106 M⊙) extremely metal-poor galaxies (EMPGs) with a 2% solar oxygen abundance (O/H)⊙ and a high specific star formation rate (sSFR ~ 300 Gyr-1) and other (extremely...
令和3年 5月 The Astrophysical Journal
Planetesimals are believed to be formed by the coagulation of dust grains in the protoplanetary disk turbulence. However, the bouncing and fragmentation barriers have not been completely solved, particularly for silicate dust. To circumvent these bar...
令和3年 4月 The Astrophysical Journal
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