313 citations · 3.7k across the 81 of their papers we have counts for
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Cross-Correlation between UHECR Arrival Distribution and Large-Scale Structure
Hajime Takami, Takahiro Nishimichi, Kazuhiro Yahata +1
We investigate correlation between the arrival directions of ultra-high-energy cosmic rays (UHECRs) and the large-scale structure (LSS) of the Universe by using statistical quantit…
Implications to Sources of Ultra-high-energy Cosmic Rays from their Arrival Distribution
Hajime Takami, Katsuhiko Sato
We estimate the local number density of sources of ultra-high-energy cosmic rays (UHECRs) based on the statistical features of their arrival direction distribution. We calculate th…
Non-thermal neutrinos from supernovae leaving a magnetar
Shunsaku Horiuchi, Yudai Suwa, Hajime Takami +2
Under the fossil field hypothesis of the origin of magnetar magnetic fields, the magnetar inherits its magnetic field from its progenitor. We show that during the supernova of such…
Impact of Rotation on Neutrino Emission and Relic Neutrino Background from Population III Stars
Yudai Suwa, Tomoya Takiwaki, Kei Kotake +1
We study the effects of rotation on the neutrino emission from Population III (Pop III) stars by performing a series of two-dimensional rotational collapse simulations of Pop III s…
Special Relativistic Simulations of Magnetically-dominated Jets in Collapsing Massive Stars
Tomoya Takiwaki, Kei Kotake, Katsuhiko Sato
We perform a series of two-dimensional magnetohydrodynamic core-collapse simulations of rapidly rotating and strongly magnetized massive stars. To study the properties of magnetic…
Distortion of Ultra-high-energy sky by Galactic Magnetic Field
Hajime Takami, Katsuhiko Sato
We investigate the deflections of UHE protons by Galactic magnetic field(GMF) using four conventional GMF models in order to discuss the positional correlation between the arrival…
Estimation Prospects of the Source Number Density of Ultra-high-energy Cosmic Rays
Hajime Takami, Katsuhiko Sato
We discuss the possibility of accurately estimating the source number density of ultra-high-energy cosmic rays (UHECRs) using small-scale anisotropy in their arrival distribution.…
Towards unravelling the structural distribution of ultra-high-energy cosmic ray sources
Hajime Takami, Katsuhiko Sato
We investigate the possibility that near future observations of ultra-high-energy cosmic rays (UHECRs) can unveil their local source distribution, which reflects the observed local…
Gravitational Wave Background from Population III Stars
Yudai Suwa, Tomoya Takiwaki, Kei Kotake +1
We estimate the gravitational wave (GW) background from Population III (Pop III) stars using the results from our hydrodynamic simulations (Suwa et al. 2007). We calculate gravitat…
Magnetorotational Collapse of Population III Stars
Yudai Suwa, Tomoya Takiwaki, Kei Kotake +1
We perform a series of two-dimensional magnetorotational core-collapse simulations of Pop III stars. Changing the initial distributions of rotation and magnetic fields prior to col…
Cosmogenic neutrinos as a probe of the transition from Galactic to extragalactic cosmic rays
Hajime Takami, Kohta Murase, Shigehiro Nagataki +1
There are two promising scenarios that explain the ankle, which is a dip in the spectrum of cosmic rays at eV. A scenario interprets the ankle as the transition from…
Reply to 'Comment on 'Heavy element production in inhomogeneous big bang nucleosynthesis''
Shunji Matsuura, Shin-ichirou Fujimoto, Masa-aki Hashimoto +1
This is a reply report to astro-ph/0604264. We studied heavy element production in high baryon density region in early universe astro-ph/0507439. However it is claimed in astro-ph/…
Impact of nuclear "pasta" on neutrino transport in collapsing stellar cores
Hidetaka Sonoda, Gentaro Watanabe, Katsuhiko Sato +3
Nuclear ``pasta'', nonspherical nuclei in dense matter, is predicted to occur in collapsing supernova cores. We show how pasta phases affect the neutrino transport cross section vi…
Mass spectrum of primordial black holes from inflationary perturbation in the Randall-Sundrum braneworld: a limit on blue spectra
Yuuiti Sendouda, Shigehiro Nagataki, Katsuhiko Sato
The mass spectrum of the primordial black holes formed by density perturbation in the radiation-dominated era of the Randall-Sundrum type-2 cosmology is given. The spectrum coincid…
Magnetohydrodynamic Simulations of A Rotating Massive Star Collapsing to A Black Hole
Shin-ichiro Fujimoto, Kei Kotake, Shoichi Yamada +2
We perform two-dimensional, axisymmetric, magnetohydrodynamic simulations of the collapse of a rotating star of 40 Msun and in the light of the collapsar model of gamma-ray burst.…
Explosive Nucleosynthesis in GRB Jets Accompanied by Hypernovae
Shigehiro Nagataki, Akira Mizuta, Katsuhiko Sato
Two-dimensional hydrodynamic simulations are performed to investigate explosive nucleosynthesis in a collapsar using the model of MacFadyen and Woosley (1999). It is shown that 56N…
Toward Radiation-Magnetohydrodynamic Simulations in Core-Collapse Supernovae
Kei Kotake, Naofumi Ohnishi, Shoichi Yamada +1
We report a current status of our radiation-magnetohydrodynamic code for the study of core-collapse supernovae. In this contribution, we discuss the accuracy of our newly developed…
Explosion Mechanism, Neutrino Burst, and Gravitational Wave in Core-Collapse Supernovae
Kei Kotake, Katsuhiko Sato, Keitaro Takahashi
Core-collapse supernovae are among the most energetic explosions in the universe marking the catastrophic end of massive stars. In spite of rigorous studies for several decades, we…
Propagation of Ultra-High Energy Cosmic Rays above eV in a Structured Extragalactic Magnetic Field and Galactic Magnetic Field
Hajime Takami, Hiroyuki Yoshiguchi, Katsuhiko Sato
We present numerical simulations on propagation of Ultra-High Energy Cosmic Rays (UHECRs) above eV in a structured extragalactic magnetic field (EGMF) and simulate their…
R-Process Nucleosynthesis in MHD Jet Explosions of Core-Collapse Supernovae
Sunao Nishimura, Kei Kotake, Masa-aki Hashimoto +4
We investigate -process nucleosynthesis during the magnetohydrodynamical (MHD) explosion of supernova in a massive star of 13 . Contrary to the case of the spherical…
North-South Neutrino Heating Asymmetry in Strongly Magnetized and Rotating Stellar Cores
Kei Kotake, Shoichi Yamada, Katsuhiko Sato
We perform a series of two-dimensional magnetohydrodynamic simulations of supernova cores. Since the distributions of the angular momentum and the magnetic fields of strongly magne…
Magneto-driven Shock Waves in Core-Collapse Supernova
Tomoya Takiwaki, Kei Kotake, Shigehiro Nagataki +1
We perform a series of two-dimensional magnetohydrodynamic simulations of the rotational core-collapse of a magnetized massive star. We employ a realistic equation of state and tak…
Sub-GeV galactic cosmic-ray antiprotons from primordial black holes in the Randall-Sundrum braneworld
Yuuiti Sendouda, Kazunori Kohri, Shigehiro Nagataki +1
We investigate cosmic-ray antiprotons emitted from the galactic primordial black holes in the Randall-Sundrum type-2 braneworld. The recent results of the BESS antiproton observati…
Affleck-Dine Baryogenesis and heavy elements production from Inhomogeneous Big Bang Nucleosynthesis
Shunji Matsuura, Alexander. D. Dolgov, Shigehiro Nagataki +1
We study the impact of possible high density baryonic bubbles on the early formed QSO, IGM, and metal poor stars. Such bubbles could be created, under certain conditions, in Afflec…