Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Local and nonlocal magnetic diffusion and alpha-effect tensors in shear
  flow turbulence   Various approaches to estimate turbulent transport coefficients from
numerical simulations of hydromagnetic turbulence are discussed. A quantitative
comparison between the averaged magnetic field obtained from a specific
three-dimensional simulation of a rotating turbulent shear flow in a slab and a
simple one-dimensional alpha-omega dynamo model is given. A direct
determination of transport coefficients is attempted by calculating the
correlation matrix of different components of the field and its derivatives.
The alpha-effect operating on the toroidal field is found to be negative and of
similar magnitude as the value obtained previously by correlating the
electromotive force with the mean magnetic field. The turbulent diffusion of
the toroidal field is comparable to the kinematic viscosity that was determined
earlier by comparing the stress with the shear. However, the turbulent
diffusion of the radial field component is smaller and can even be formally
negative. The method is then modified to obtain the spectral dependence of the
turbulent transport coefficients on the wavenumber. There is evidence for
nonlocal behavior in that most of the response comes from the smallest
wavenumbers corresponding to the largest scale possible in the simulation.

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The categories of this paper are: atom-ph
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci