Comparing Poynting flux dominated magnetic tower jets with kinetic-energy dominated jets

Journal Article · Fri Feb 08 00:00:00 EST 2013 · High Energy Density Physics

DOI:https://doi.org/10.1016/j.hedp.2013.01.010· OSTI ID:1462542

Huarte-Espinosa, M. ^[1]; Frank, A. ^[1]; Blackman, E. G. ^[1]; Ciardi, A. ^[2]; Hartigan, P. ^[3]; Lebedev, S. V. ^[4]; Chittenden, J. P. ^[4]

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1. Univ. of Rochester, NY (United States). Dept. of Physics and Astronomy
2. Pierre and Marie Curie Univ., Paris (France). Paris Observatory (OP) and Lab. of Radiation and Matter Studies in Astrophysics and Atmospheres (LERMA); Higher Normal School, UMR 8112 CNRS, Paris (France)
3. Rice Univ., Houston, TX (United States). Dept. of Physics and Astronomy
4. Imperial College, London (United Kingdom). Blackett Lab.

Magnetic towers represent one of two fundamental forms of MHD out flows. Driven by magnetic pressure gradients, these flows have been less well studied than magneto-centrifugally launched jets even though magnetic towers may well be as common. We present new results exploring the behavior and evolution of magnetic tower outflows and demonstrate their connection with pulsed power experimental studies and purely hydrodynamic jets which might represent the asymptotic propagation regimes of magneto-centrifugally launched jets. High-resolution AMR MHD simulations (using the AstroBEAR code) provide insights into the underlying physics of magnetic towers and help us constrain models of their propagation. Our simulations have been designed to explore the effects of thermal energy losses and rotation on both towerflows and their hydro counterparts. We find these parameters have significant effects on the stability of magnetic towers, but mild effects on the stability of hydro jets. Current-driven perturbations in the Poynting Flux Dominated (PDF) towers are shown to be amplified in both the cooling and rotating cases. Our studies of the long term evolution of the towers show that the formation of weakly magnetized central jets within the tower are broken up by these instabilities becoming a series of collimated clumps which magnetization properties vary over time. In addition to discussing these results in light of laboratory experiments, we address their relevance to astrophysical observations of young star jets and outflow from highly evolved solar type stars.

• Research Organization: Rice Univ., Houston, TX (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); Space Telescope Science Inst., Baltimore, MD (United States); National Science Foundation (NSF); Cornell Univ., Ithaca, NY (United States)
• Grant/Contract Number: NA0002037; HST-AR-11251.01-A; HST-AR-12128.01-A; AST-0807363; PHY0903797; SC0001063; 41843-7012; FC52-08NA28302
• OSTI ID: 1462542
• Report Number(s): DOE-Rice-2037-8; PII: S1574181813000165; TRN: US1902187
• Journal Information: High Energy Density Physics, Vol. 9, Issue 2; ISSN 1574-1818
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
Jets and outflows
Methods: numerical
Magnetic field
Supersonic shocks