Numerical modeling of space plasma processes

JAXA Supercomputer System Annual Report April 2019-March 2020

Report Number: R19EACA28

Subject Category: JSS2 Inter-University Research

Responsible Representative: Seiji Zenitani, Project Associate Professor, Kobe University
Contact Information: Seiji Zenitani(zenitani@port.kobe-u.ac.jp)
Members: Seiji Zenitani, Iku Shinohara, Takahiro Miyoshi

Abstract

This project investigates basic processes in space plasmas, by using supercomputer simulations. In particular, we study “magnetic reconnection” in space, an abrupt change in magnetic topology. In order to support research activities by ourselves and by other groups, we develop massively-parallel simulation codes. They are publicly available on the Internet.

Reference URL

Please refer to ‘OpenMHD code‘.

Reasons and benefits of using JAXA Supercomputer System

Space plasma processes are basically described by magnetohydrodynamics (MHD) equations, which are notoriously complex. Supercomputer simulation is necessary to predict the nonlinear evolution of the system.

Achievements of the Year

We have studied basic properties of plasmoid-dominated turbulent reconnection in solar coronal conditions. By carrying out a series of magnetohydrodynamic (MHD) simulations, we have found that the flux tranfer rate becomes faster than expected [4]. We have also developped a high-accuracy numerical scheme for particle-in-cell (PIC) simulations to study kinetic plasma phenomena [1].

Publications

– Peer-reviewed papers

[1] S. Zenitani & T. N. Kato, Multiple Boris integrators for particle-in-cell simulation, Comput. Phys. Commun., 247, 106954 (2020)

[2] W.-L. Teh & S. Zenitani, Thermodynamic Properties of Mirror Structures in the Magnetosheath: MMS Observations and Double-Polytropic MHD Simulations, Astrophys. J., 885, 22 (2019)

[3] W.-L. Teh & S. Zenitani, Thermodynamics of Dipolarization Fronts of Magnetic Reconnection in Anisotropic Plasma: MMS Observations and Resistive Double-polytropic MHD Simulations, Astrophys. J., 890, 114 (2020)

– Other

[4] S. Zenitani & T. Miyoshi, Plasmoid-dominated turbulent reconnection in a low beta plasma, submitted to Astrophys. J. Letters

Usage of JSS2

Computational Information

Process Parallelization Methods: MPI
Thread Parallelization Methods: OpenMP
Number of Processes: 40 – 2000
Elapsed Time per Case: 36 Hour(s)

Resources Used

Fraction of Usage in Total Resources*1(%): 0.00

Details

Please refer to System Configuration of JSS2 for the system configuration and major specifications of JSS2.

Computational Resources
System Name	Amount of Core Time (core x hours)	Fraction of Usage*2(%)
SORA-MA	3,609.70	0.00
SORA-PP	0.00	0.00
SORA-LM	0.00	0.00
SORA-TPP	0.00	0.00

File System Resources
File System Name	Storage Assigned (GiB)	Fraction of Usage*2(%)
/home	67.29	0.06
/data	1,228.12	0.02
/ltmp	3,146.70	0.27

Archiver Resources
Archiver Name	Storage Used (TiB)	Fraction of Usage*2(%)
J-SPACE	0.00	0.00

*1: Fraction of Usage in Total Resources: Weighted average of three resource types (Computing, File System, and Archiver).

*2: Fraction of Usage：Percentage of usage relative to each resource used in one year.