109 citations · 549 across the 25 of their papers we have counts for
25 papers
Bifurcated Impact of Neutrino Fast Flavor Conversion on Core-collapse Supernovae Informed by Multi-angle Neutrino Radiation Hydrodynamics
Ryuichiro Akaho, Hiroki Nagakura, Wakana Iwakami +6
In this {\it Letter}, we present a compelling and robust argument for the roles of neutrino fast flavor conversion (FFC) in the explosion mechanism of core-collapse supernova (CCSN…
Observing Supernova Neutrino Light Curves with Super-Kamiokande.VI. A Practical Data Analysis Technique Considering Realistic Experimental Backgrounds
Fumi Nakanishi, Ken'ichiro Nakazato, Masayuki Harada +9
Neutrinos from supernovae, especially those emitted during the late phase of core collapse, are essential for understanding the final stages of massive star evolution. We have been…
Neutrino Constraints on Black Hole Formation in M31
Yudai Suwa, Ryuichiro Akaho, Yosuke Ashida +9
We investigate neutrino signals associated with black hole formation resulting from the gravitational collapse of massive stars, motivated by the candidate failed supernova M31-201…
An Extended Closure Relation by LightGBM for Neutrino Radiation Transport in Core-collapse Supernovae
Shota Takahashi, Akira Harada, Shoichi Yamada
We developed a machine learning model using LightGBM, one of the most popular gradient-boosting decision tree methods these days, to predict the Eddington tensor, or the second-ord…
Observing Supernova Neutrino Light Curves with Super-Kamiokande. V. Distance Estimation with Neutrinos
Yudai Suwa, Akira Harada, Masamitsu Mori +7
Neutrinos are pivotal signals in multi-messenger observations of supernovae (SNe). Recent advancements in the analysis method of supernova (SN) neutrinos, especially in quantitativ…
Machine Learning-Based Detection of Non-Axisymmetric Fast Neutrino Flavor Instabilities in Core-Collapse Supernovae
Sajad Abbar, Akira Harada, Hiroki Nagakura
In dense neutrino environments like core-collapse supernovae (CCSNe) and neutron star mergers (NSMs), neutrinos can undergo fast flavor conversions (FFC) when their angular distrib…
Observing Supernova Neutrino Light Curves with Super-Kamiokande. IV. Development of SPECIAL BLEND: a New Public Analysis Code for Supernova Neutrinos
Akira Harada, Yudai Suwa, Masayuki Harada +6
Supernova neutrinos are invaluable signals that offer information about the interior of supernovae. Because a nearby supernova can occur at any time, preparing for future supernova…
Effects of nuclear matter and composition in core-collapse supernovae and long-term proto-neutron star cooling
Kohsuke Sumiyoshi, Shun Furusawa, Hiroki Nagakura +4
We study the influence of hot and dense matter in core-collapse supernovae by adopting up-to-date nuclear equation of state (EOS) based on the microscopic nuclear many-body framewo…
Protoneutron Star Convection Simulated with a New General Relativistic Boltzmann Neutrino Radiation-Hydrodynamics Code
Ryuichiro Akaho, Akira Harada, Hiroki Nagakura +6
We investigate the protoneutron star (PNS) convection using our newly developed general relativistic Boltzmann neutrino radiation-hydrodynamics code. This is a pilot study for more…
Observing Supernova Neutrino Light Curves with Super-Kamiokande. III. Extraction of Mass and Radius of Neutron Stars from Synthetic Data
Yudai Suwa, Akira Harada, Masayuki Harada +6
Neutrinos are guaranteed to be observable from the next galactic supernova (SN). Optical light and gravitational waves are also observable, but may be difficult to observe if the l…
Prospects of fast flavor neutrino conversion in rotating core-collapse supernovae
Akira Harada, Hiroki Nagakura
There is mounting evidence that neutrinos undergo fast flavor conversion (FFC) in core-collapse supernova (CCSN). In this letter, we investigate the roles of stellar rotation on th…
Principal-Axis Analysis of the Eddington Tensor for the Early Post-Bounce Phase of Rotational Core-Collapse Supernovae
Wakana Iwakami, Akira Harada, Hiroki Nagakura +6
Using full Boltzmann neutrino transport, we performed two-dimensional (2D) core-collapse supernova simulations in axisymmetry for two progenitor models with 11.2M and 15.0M both ro…
Observing Supernova Neutrino Light Curves with Super-Kamiokande. II. Impact of the Nuclear Equation of State
Ken'ichiro Nakazato, Fumi Nakanishi, Masayuki Harada +6
The late-time evolution of the neutrino event rate from supernovae is evaluated for Super-Kamiokande using simulated results of proto-neutron star (PNS) cooling. In the present wor…
Gravitational Wave Physics and Astronomy in the nascent era
Makoto Arimoto, Hideki Asada, Michael L. Cherry +50
The detections of gravitational waves (GW) by LIGO/Virgo collaborations provide various possibilities to physics and astronomy. We are quite sure that GW observations will develop…
Deep Learning of the Eddington Tensor in the Core-collapse Supernova Simulation
Akira Harada, Shota Nishikawa, Shoichi Yamada
We trained deep neural networks (DNNs) as a function of the neutrino energy density, flux, and the fluid velocity to reproduce the Eddington tensor for neutrinos obtained in our fi…
Developing an end-to-end simulation framework of supernova neutrino detection
Masamitsu Mori, Yudai Suwa, Ken'ichiro Nakazato +5
Massive stars can explode as supernovae at the end of their life cycle, releasing neutrinos whose total energy reaches erg. Moreover, neutrinos play key roles in supernov…
Multidimensional Boltzmann Neutrino Transport Code in Full General Relativity for Core-collapse Simulations
Ryuichiro Akaho, Akira Harada, Hiroki Nagakura +6
We develop a neutrino transfer code for core-collapse simulations, that directly solves the multidimensional Boltzmann equations in full general relativity. We employ the discrete…
Analytic solutions for neutrino-light curves of core-collapse supernovae
Yudai Suwa, Akira Harada, Ken'ichiro Nakazato +1
Neutrinos are a guaranteed signal from supernova explosions in the Milky Way, and a most valuable messenger that can provide us with information about the deepest parts of supernov…
Simulations of the Early Post-Bounce Phase of Core-Collapse Supernovae in Three-Dimensional Space with Full Boltzmann Neutrino Transport
Wakana Iwakami, Hirotada Okawa, Hiroki Nagakura +5
We report on the core-collapse supernova simulation we conducted for a 11.2 M progenitor model in three-dimensional space up to 20 ms after bounce, using a radiation hydrodynamics…
The Boltzmann-radiation-hydrodynamics Simulations of Core-collapse Supernovae with Different Equations of State: the Role of Nuclear Composition and the Behavior of Neutrinos
Akira Harada, Hiroki Nagakura, Wakana Iwakami +5
Using the Boltzmann-radiation-hydrodynamics code, which solves the Boltzmann equation for neutrino transport, we present the results of the simulations with the nuclear equations o…
Fast collective neutrino oscillations inside the neutrino sphere in core-collapse supernovae
Milad Delfan Azari, Shoichi Yamada, Taiki Morinaga +6
Neutrinos are believed to have a key role in the explosion mechanism of core-collapse supernovae as they carry most of the energy released by the gravitational collapse of a massiv…
On the Neutrino Distributions in Phase Space for the Rotating Core-collapse Supernova Simulated with a Boltzmann-neutrino-radiation-hydrodynamics Code
Akira Harada, Hiroki Nagakura, Wakana Iwakami +5
With the Boltzmann-radiation-hydrodynamics code, which we have developed to solve numerically the Boltzmann equations for neutrino transfer, the Newtonian hydrodynamics equations,…
A Parametric Study of the Acoustic Mechanism for Core-Collapse Supernovae
A. Harada, H. Nagakura, W. Iwakami +1
We investigate the criterion for the acoustic mechanism to work successfully in core-collapse supernovae. The acoustic mechanism is an alternative to the neutrino-heating mechanism…
Simulations of core-collapse supernovae in spatial axisymmetry with full Boltzmann neutrino transport
Hiroki Nagakura, Wakana Iwakami, Shun Furusawa +6
We present the first results of our spatially axisymmetric core-collapse supernova simulations with full Boltzmann neutrino transport, which amount to a time-dependent 5-dimensiona…