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Self-collimated axial jet seeds from thin accretion disks
Giulio Tirabassi1, Giovanni Montani, Nakia Carlevaro
1Physics Department, "Sapienza" University of Rome, Piazzale Aldo Moro 5, 00185 Roma, Italy and Department of Physics and Nuclear Engineering, Universitat Politecnica de Catalunya, Barcelona, Spain.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 16, 2013
Summary
A magnetic field
Area of Science:
- Astrophysics
- Plasma Physics
- Magnetohydrodynamics
Background:
- Accretion disks are crucial in astrophysics, powering phenomena like active galactic nuclei and protostellar jets.
- Understanding jet formation mechanisms from accretion disks is a long-standing challenge.
Purpose of the Study:
- To investigate how a stationary crystalline magnetic field structure influences accretion disk fragmentation.
- To explain the generation of axial jet seeds and their collimation properties.
Main Methods:
- Theoretical modeling of accretion disk dynamics under a specific magnetic field configuration.
- Analysis of plasma behavior, including fragmentation and jet formation, within this model.
Main Results:
- A stationary crystalline magnetic field structure can induce partial accretion disk fragmentation.
- This fragmentation generates an axial jet seed with a funnel-like, twisted hot plasma structure.
- The model predicts a high degree of jet collimation and ejection due to dissipative effects.
Conclusions:
- The proposed magnetic field structure offers a viable mechanism for axial jet seed formation.
- The model's predicted accretion rates align with observational data, supporting its relevance.
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