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Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet.

ABSTRACT: The remarkable discovery by the Chandra X-ray observatory that the Crab nebula's jet periodically changes direction provides a challenge to our understanding of astrophysical jet dynamics. It has been suggested that this phenomenon may be the consequence of magnetic fields and magnetohydrodynamic instabilities, but experimental demonstration in a controlled laboratory environment has remained elusive. Here we report experiments that use high-power lasers to create a plasma jet that can be directly compared with the Crab jet through well-defined physical scaling laws. The jet generates its own embedded toroidal magnetic fields; as it moves, plasma instabilities result in multiple deflections of the propagation direction, mimicking the kink behaviour of the Crab jet. The experiment is modelled with three-dimensional numerical simulations that show exactly how the instability develops and results in changes of direction of the jet.

SUBMITTER: Li CK

PROVIDER: S-EPMC5059765 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet.

Li C K CK Tzeferacos P P Lamb D D Gregori G G Norreys P A PA Rosenberg M J MJ Follett R K RK Froula D H DH Koenig M M Seguin F H FH Frenje J A JA Rinderknecht H G HG Sio H H Zylstra A B AB Petrasso R D RD Amendt P A PA Park H S HS Remington B A BA Ryutov D D DD Wilks S C SC Betti R R Frank A A Hu S X SX Sangster T C TC Hartigan P P Drake R P RP Kuranz C C CC Lebedev S V SV Woolsey N C NC

Nature communications 20161007

The remarkable discovery by the Chandra X-ray observatory that the Crab nebula's jet periodically changes direction provides a challenge to our understanding of astrophysical jet dynamics. It has been suggested that this phenomenon may be the consequence of magnetic fields and magnetohydrodynamic instabilities, but experimental demonstration in a controlled laboratory environment has remained elusive. Here we report experiments that use high-power lasers to create a plasma jet that can be direct ...[more]

PMID: 27713403

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Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet.

Publications

Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet.

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