Numerical simulations of Hall MHD small-scale dynamos

GOMEZ, DANIEL; MININNI, PABLO; DMITRUK, PABLO

Rio de Janeiro, Brasil

Congreso; XXVII General Assembly of the International Astronomical Union; 2009

International Astronomical Union

The generation of magnetic fields by dynamo activity plays a very important role in a variety of astrophysical objects. Under certain conditions, the turbulent flows that are ubiquitous in many of these objects, are shown to generate intense magnetic fields both theoretically and numerically.Much of the progress in our understanding of dynamo mechanisms, has been made within the theoretical framework of magnetohydrodynamics (MHD). However, for sufficiently diffuse media, the Hall effect eventually becomes non-negligible. We present results from three dimensional simulations of the Hall-MHDequations subjected to non-helical forcing. The simulations are performed with a pseudospectral code to achieve exponentially fast convergence. We study the role of the Hall effect in the dynamo efficiency for different values of the Prandtl number.