Luke Chamandy

Non-linear galactic dynamos: a toolbox

We compare various models and approximations for non-linear mean-field dynamos in disc galaxies to assess their applicability and accuracy, and thus to suggest a set of simple solutions suitable to model the large-scale galactic magnetic fields in various contexts. The dynamo saturation mechanisms considered are the magnetic helicity balance involving helicity fluxes (the dynamical

Galactic spiral patterns and dynamo action – II. Asymptotic solutions

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Magnetic spiral arms and galactic outflows

-quenching) and an algebraic

NONLINEAR GALACTIC DYNAMOS AND THE MAGNETIC PITCH ANGLE

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Magnetic arms generated by multiple interfering galactic spiral patterns

-quenching. The non-linear solutions are then compared with the marginal kinematic and asymptotic solutions. We also discuss the accuracy of the no-

STATISTICAL TESTS OF GALACTIC DYNAMO THEORY

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A new constraint on mean-field galactic dynamo theory

approximation. Although these tools are very different in the degree of approximation and hence complexity, they all lead to remarkably similar solutions for the mean magnetic field. In particular, we show that the algebraic

Galactic spiral patterns and dynamo action

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Galactic spiral patterns and dynamo action – I. A new twist on magnetic arms

-quenching non-linearity can be obtained from a more physical dynamical

An analytical dynamo solution for large-scale magnetic fields of galaxies

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