Over the geological ages, the Earth has undergone several erratic reversals of its magnetic field. The sun’s magnetic field is reversed regularly every 22 years according to its cycle. These magnetic dynamics, which are still shrouded in mystery, play a role in our planet’s exposure to cosmic rays. With the CEA team of
F. Daviaud, the joint VKS experiment CEA-CNRS-ENS Lyon and Paris has, for the very first time, been able to observe magnetic field reversals in laboratory conditions thanks to a highly turbulent flow of liquid sodium. The experiments should help scientists to understand more about cosmic magnetic field reversals. The results are published in Europhysics Letters, Volume 77, March 2007.
The CEA-CNRS-ENS press realease.
WEB site of the VKS team.
M. Berhanu, R. Monchaux, S. Fauve, N. Mordant, F. Pétrélis, A. Chiffaudel, F. Daviaud, B. Dubrulle, C. Gasquet, L. Marié, and F. Ravelet, M. Bourgoin, Ph. Odier, M. Moulin, J.-F. Pinton, R. Volk,
Magnetic field reversals in an experimental turbulent dynamo, Europhys. Lett. 77 (2007) 59001.
R. Monchaux, M. Berhanu, M. Bourgoin, M. Moulin, Ph. Odier, J.-F. Pinton, R. Volk, S. Fauve, N. Mordant, F. Pétrélis, A. Chiffaudel, F. Daviaud, B. Dubrulle, C. Gasquet, L. Marié, and F. Ravelet
Generation of a Magnetic Field by Dynamo Action in a Turbulent Flow of Liquid Sodium,
Phys. Rev. Lett. 98 (2007) 044502.
See also the first DRECAM/SPEC highlight :
Generation of a magnetic field by dynamo action in a turbulent flow (On the origin of the earth magnetic field…).
