We demonstrate that a magneto-convection simulation incorporating essentialphysical processes governing solar surface convection exhibits turbulentsmall-scale dynamo action. By presenting a derivation of the energy balanceequation and transfer functions for compressible magnetohydrodynamics (MHD), wequantify the source of magnetic energy on a scale-by-scale basis. We rule outthe two alternative mechanisms for the generation of small-scale magnetic fieldin the simulations: the tangling of magnetic field lines associated with theturbulent cascade and Alfvenization of small-scale velocity fluctuations("turbulent induction"). Instead, we find the dominant source of small-scalemagnetic energy is stretching by inertial-range fluid motions of small-scalemagnetic field lines against the magnetic tension force to produce (againstOhmic dissipation) more small-scale magnetic field. The scales involved becomesmaller with increasing Reynolds number, which identifies the dynamo as asmall-scale turbulent dynamo.
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