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Title: Three-dimensional Boltzmann-Hydro Code for Core-collapse in Massive Stars. II. The Implementation of Moving-mesh for Neutron Star Kicks

Abstract

We present a newly developed moving-mesh technique for the multi-dimensional Boltzmann-Hydro code for the simulation of core-collapse supernovae (CCSNe). What makes this technique different from others is the fact that it treats not only hydrodynamics but also neutrino transfer in the language of the 3 + 1 formalism of general relativity (GR), making use of the shift vector to specify the time evolution of the coordinate system. This means that the transport part of our code is essentially general relativistic, although in this paper it is applied only to the moving curvilinear coordinates in the flat Minknowski spacetime, since the gravity part is still Newtonian. The numerical aspect of the implementation is also described in detail. Employing the axisymmetric two-dimensional version of the code, we conduct two test computations: oscillations and runaways of proto-neutron star (PNS). We show that our new method works fine, tracking the motions of PNS correctly. We believe that this is a major advancement toward the realistic simulation of CCSNe.

Authors:
 [1];  [2];  [3];  [4];  [5];  [6];  [7]
  1. TAPIR, Walter Burke Institute for Theoretical Physics, Mailcode 350-17, California Institute of Technology, Pasadena, CA 91125 (United States)
  2. Yukawa Institute for Theoretical Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 (Japan)
  3. Center for Computational Astrophysics, National Astronimical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan)
  4. Numazu College of Technology, Ooka 3600, Numazu, Shizuoka 410-8501 (Japan)
  5. Advanced Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan)
  6. High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 308-0801 (Japan)
  7. University of Tsukuba, 1-1-1, Tennodai Tsukuba, Ibaraki 305-8577 (Japan)
Publication Date:
OSTI Identifier:
22661129
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal, Supplement Series; Journal Volume: 229; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AXIAL SYMMETRY; CALCULATION METHODS; COMPUTER CODES; CURVILINEAR COORDINATES; GENERAL RELATIVITY THEORY; GRAVITATION; GRAVITATIONAL COLLAPSE; HYDRODYNAMICS; IMPLEMENTATION; MINKOWSKI SPACE; NEUTRON STARS; OSCILLATIONS; PROTOSTARS; RADIANT HEAT TRANSFER; RELATIVISTIC RANGE; SPACE-TIME; SUPERNOVAE; THREE-DIMENSIONAL CALCULATIONS; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Nagakura, Hiroki, Iwakami, Wakana, Furusawa, Shun, Sumiyoshi, Kohsuke, Yamada, Shoichi, Matsufuru, Hideo, and Imakura, Akira. Three-dimensional Boltzmann-Hydro Code for Core-collapse in Massive Stars. II. The Implementation of Moving-mesh for Neutron Star Kicks. United States: N. p., 2017. Web. doi:10.3847/1538-4365/AA69EA.
Nagakura, Hiroki, Iwakami, Wakana, Furusawa, Shun, Sumiyoshi, Kohsuke, Yamada, Shoichi, Matsufuru, Hideo, & Imakura, Akira. Three-dimensional Boltzmann-Hydro Code for Core-collapse in Massive Stars. II. The Implementation of Moving-mesh for Neutron Star Kicks. United States. doi:10.3847/1538-4365/AA69EA.
Nagakura, Hiroki, Iwakami, Wakana, Furusawa, Shun, Sumiyoshi, Kohsuke, Yamada, Shoichi, Matsufuru, Hideo, and Imakura, Akira. Sat . "Three-dimensional Boltzmann-Hydro Code for Core-collapse in Massive Stars. II. The Implementation of Moving-mesh for Neutron Star Kicks". United States. doi:10.3847/1538-4365/AA69EA.
@article{osti_22661129,
title = {Three-dimensional Boltzmann-Hydro Code for Core-collapse in Massive Stars. II. The Implementation of Moving-mesh for Neutron Star Kicks},
author = {Nagakura, Hiroki and Iwakami, Wakana and Furusawa, Shun and Sumiyoshi, Kohsuke and Yamada, Shoichi and Matsufuru, Hideo and Imakura, Akira},
abstractNote = {We present a newly developed moving-mesh technique for the multi-dimensional Boltzmann-Hydro code for the simulation of core-collapse supernovae (CCSNe). What makes this technique different from others is the fact that it treats not only hydrodynamics but also neutrino transfer in the language of the 3 + 1 formalism of general relativity (GR), making use of the shift vector to specify the time evolution of the coordinate system. This means that the transport part of our code is essentially general relativistic, although in this paper it is applied only to the moving curvilinear coordinates in the flat Minknowski spacetime, since the gravity part is still Newtonian. The numerical aspect of the implementation is also described in detail. Employing the axisymmetric two-dimensional version of the code, we conduct two test computations: oscillations and runaways of proto-neutron star (PNS). We show that our new method works fine, tracking the motions of PNS correctly. We believe that this is a major advancement toward the realistic simulation of CCSNe.},
doi = {10.3847/1538-4365/AA69EA},
journal = {Astrophysical Journal, Supplement Series},
number = 2,
volume = 229,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
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