201 citations · 258 across the 14 of their papers we have counts for
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The Structure of Poloidal Fields Embedded in Thin Disks
Yossef Zenati, Ethan T. Vishniac, Amir Jafari
Many accreting systems are modeled as geometrically thin disks. Simulations of accretion disks cannot be extended to this regime, although local models can address the behavior of…
Nanoflare Theory Revisited
Amir Jafari, Ethan Vishniac, Siyao Xu
Local magnetic reversals are an inseparable part of magnetohydrodynamic (MHD) turbulence whose collective outcome on an arbitrary scale in the inertial range may lead to a global s…
Power and spatial complexity in stochastic reconnection
Amir Jafari, Ethan Vishniac, Vignesh Vaikundaraman
The level of spatial complexity associated with a given vector field on an arbitrary range of scales \iffalse can be quantified by a simple, time-dependent function…
3D Turbulent Reconnection: Theory, Tests and Astrophysical Implications
Alex Lazarian, Gregory L. Eyink, Amir Jafari +4
Magnetic reconnection, topological change in magnetic fields, is a fundamental process in magnetized plasmas. It is associated with energy release in regions of magnetic field anni…
Magnetic topology in fluids
Amir Jafari, Ethan Vishniac
We study the evolution of turbulent magnetic fields from a topological point of view, invoking commonplace mathematical tools from general topology and dynamical systems theory whi…
Topological theory of physical fields
Amir Jafari, Ethan Vishniac
We study the topology associated with physical vector and scalar fields. A mathematical object, e.g., a ball, can be continuously deformed, without tearing or gluing, to make other…
Statistical Analysis of Stochastic Magnetic Fields
Amir Jafari, Ethan Vishniac, Vignesh Vaikundaraman
Previous work has introduced scale-split energy density ψfor a given vector field B in order to quantify the field stochasticity S(t). Application to turbulent magnetic fields lead…
Magnetic stochasticity and diffusion
Amir Jafari, Ethan Vishniac, Vignesh Vaikundaraman
We develop a quantitative relationship between magnetic diffusion and the level of randomness, or stochasticity, of the diffusing magnetic field in a magnetized medium. A general m…
Electromagnetic Helicity in Classical Physics
Amir Jafari
This pedagogical note revisits the concept of electromagnetic helicity in classical systems. In particular, magnetic helicity and its role in mean field dynamo theories is briefly…
Magnetic Fields in Accretion Disks: A Review
Amir Jafari
We review the current theoretical models of the inward advection of the large scale external magnetic fields in accretion discs. The most plausible theories for launching astrophys…
Introduction to Magnetic Reconnection
Amir Jafari, Ethan Vishniac
We review the basic concepts of magnetic reconnection and propose a general framework for the astrophysical reconnection at large scales. Magnetic reconnection is the rearrangement…