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Title: The Mochi LabJet Experiment for Measurements of Canonical Helicity Injection in a Laboratory Astrophysical Jet

Abstract

The Mochi device is a new pulsed power plasma experiment designed to produce long, collimated, stable, magnetized plasma jets when set up in the LabJet configuration. The LabJet configuration aims to simulate an astrophysical jet in the laboratory by mimicking an accretion disk threaded by a poloidal magnetic field with concentric planar electrodes in front of a solenoidal coil. The unique setup consists of three electrodes, each with azimuthally symmetric gas slits. Two of the electrodes are biased independently with respect to the third electrode to control the radial electric field profile across the poloidal bias magnetic field. This design approximates a shear azimuthal rotation profile in an accretion disk. The azimuthally symmetric gas slits provide a continuously symmetric mass source at the footpoint of the plasma jet, so any azimuthal rotation of the plasma jet is not hindered by a discrete number of gas holes. The initial set of diagnostics consists of current Rogowski coils, voltage probes, magnetic field probe arrays, an interferometer and ion Doppler spectroscopy, supplemented by a fast ion gauge and a retarding grid energy analyzer. The measured parameters of the first plasmas are ~10 22 m -3, ~0.4 T, and 5–25 eV, with velocities ofmore » ~20–80 km s -1. Finally, the combination of a controllable electric field profile, a flared poloidal magnetic field, and azimuthally symmetric mass sources in the experiment successfully produces short-lived (~10 μs, ≳5 Alfvén times) collimated magnetic jets with a ~10:1 aspect ratio and long-lived (~100 μs, ≳40 Alfvén times) flow-stabilized, collimated, magnetic jets with a ~30:1 aspect ratio.« less

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [2];  [2];  [2];  [2];  [2]
  1. Univ. of Washington, Seattle, WA (United States). Aeronautics & Astronautics; Univ. of Tokyo (Japan). Graduate School of Frontier Sciences
  2. Univ. of Washington, Seattle, WA (United States). Aeronautics & Astronautics
Publication Date:
Research Org.:
Univ. of Washington, Seattle, WA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
OSTI Identifier:
1458704
Report Number(s):
LLNL-JRNL-740210
Journal ID: ISSN 1538-4365; 894204
Grant/Contract Number:
SC0010340
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
The Astrophysical Journal. Supplement Series (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal. Supplement Series (Online); Journal Volume: 236; Journal Issue: 2; Journal ID: ISSN 1538-4365
Publisher:
American Astronomical Society/IOP
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 42 ENGINEERING; galaxies; jets; ISM; outflows; plasmas; stars; winds

Citation Formats

You, Setthivoine, von der Linden, Jens, Lavine, Eric Sander, Carroll, Evan Grant, Card, Alexander, Quinley, Morgan, and Azuara-Rosales, Manuel. The Mochi LabJet Experiment for Measurements of Canonical Helicity Injection in a Laboratory Astrophysical Jet. United States: N. p., 2018. Web. doi:10.3847/1538-4365/aaba6f.
You, Setthivoine, von der Linden, Jens, Lavine, Eric Sander, Carroll, Evan Grant, Card, Alexander, Quinley, Morgan, & Azuara-Rosales, Manuel. The Mochi LabJet Experiment for Measurements of Canonical Helicity Injection in a Laboratory Astrophysical Jet. United States. doi:10.3847/1538-4365/aaba6f.
You, Setthivoine, von der Linden, Jens, Lavine, Eric Sander, Carroll, Evan Grant, Card, Alexander, Quinley, Morgan, and Azuara-Rosales, Manuel. Thu . "The Mochi LabJet Experiment for Measurements of Canonical Helicity Injection in a Laboratory Astrophysical Jet". United States. doi:10.3847/1538-4365/aaba6f.
@article{osti_1458704,
title = {The Mochi LabJet Experiment for Measurements of Canonical Helicity Injection in a Laboratory Astrophysical Jet},
author = {You, Setthivoine and von der Linden, Jens and Lavine, Eric Sander and Carroll, Evan Grant and Card, Alexander and Quinley, Morgan and Azuara-Rosales, Manuel},
abstractNote = {The Mochi device is a new pulsed power plasma experiment designed to produce long, collimated, stable, magnetized plasma jets when set up in the LabJet configuration. The LabJet configuration aims to simulate an astrophysical jet in the laboratory by mimicking an accretion disk threaded by a poloidal magnetic field with concentric planar electrodes in front of a solenoidal coil. The unique setup consists of three electrodes, each with azimuthally symmetric gas slits. Two of the electrodes are biased independently with respect to the third electrode to control the radial electric field profile across the poloidal bias magnetic field. This design approximates a shear azimuthal rotation profile in an accretion disk. The azimuthally symmetric gas slits provide a continuously symmetric mass source at the footpoint of the plasma jet, so any azimuthal rotation of the plasma jet is not hindered by a discrete number of gas holes. The initial set of diagnostics consists of current Rogowski coils, voltage probes, magnetic field probe arrays, an interferometer and ion Doppler spectroscopy, supplemented by a fast ion gauge and a retarding grid energy analyzer. The measured parameters of the first plasmas are ~1022 m-3, ~0.4 T, and 5–25 eV, with velocities of ~20–80 km s-1. Finally, the combination of a controllable electric field profile, a flared poloidal magnetic field, and azimuthally symmetric mass sources in the experiment successfully produces short-lived (~10 μs, ≳5 Alfvén times) collimated magnetic jets with a ~10:1 aspect ratio and long-lived (~100 μs, ≳40 Alfvén times) flow-stabilized, collimated, magnetic jets with a ~30:1 aspect ratio.},
doi = {10.3847/1538-4365/aaba6f},
journal = {The Astrophysical Journal. Supplement Series (Online)},
number = 2,
volume = 236,
place = {United States},
year = {Thu May 17 00:00:00 EDT 2018},
month = {Thu May 17 00:00:00 EDT 2018}
}

Journal Article:
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