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arXiv · 2108.11919

Laser astrophysics experiment on the amplification of magnetic fields by shock-induced interfacial instabilities

Takayoshi Sano·Shohei Tamatani·Kazuki Matsuo·King Fai Farley Law·Taichi Morita·Shunsuke Egashira·Masato Ota·Rajesh Kumar·Hiroshi Shimogawara·Yukiko Hara·Seungho Lee·Shohei Sakata·Gabriel Rigon·Thibault Michel·Paul Mabey·Bruno Albertazzi·Michel Koenig·Alexis Casner·Keisuke Shigemori·Shinsuke Fujioka·Masakatsu Murakami·Youichi Sakawa
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Abstract

Laser experiments are becoming established as a new tool for astronomical research that complements observations and theoretical modeling. Localized strong magnetic fields have been observed at a shock front of supernova explosions. Experimental confirmation and identification of the physical mechanism for this observation are of great importance in understanding the evolution of the interstellar medium. However, it has been challenging to treat the interaction between hydrodynamic instabilities and an ambient magnetic field in the laboratory. Here, we developed an experimental platform to examine magnetized Richtmyer-Meshkov instability (RMI). The measured growth velocity was consistent with the linear theory, and the magnetic-field amplification was correlated with RMI growth. Our experiment validated the turbulent amplification of magnetic fields associated with the shock-induced interfacial instability in astrophysical conditions for the first time. Experimental elucidation of fundamental processes in magnetized plasmas is generally essential in various situations such as fusion plasmas and planetary sciences.

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Takayoshi Sano, Shohei Tamatani, Kazuki Matsuo, King Fai Farley Law, Taichi Morita, Shunsuke Egashira, Masato Ota, Rajesh Kumar, Hiroshi Shimogawara, Yukiko Hara, Seungho Lee, Shohei Sakata, Gabriel Rigon, Thibault Michel, Paul Mabey, Bruno Albertazzi, Michel Koenig, Alexis Casner, Keisuke Shigemori, Shinsuke Fujioka, Masakatsu Murakami, Youichi Sakawa. 2021-08-26. Laser astrophysics experiment on the amplification of magnetic fields by shock-induced interfacial instabilities. https://doi.org/10.1103/physreve.104.035206

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