laboratoire de physique statistique
 
 
laboratoire de physique statistique

Publications

Rechercher
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 


1
P U B L I C A T I O N S



 
2009
Direct numerical simulations of the galactic dynamo in the kinematic growing phase - Gissinger, Christophe and Fromang, Sebastien and Dormy, Emmanuel
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 394L84-L88 (2009)

Abstract : We present kinematic simulations of a galactic dynamo model based on the large-scale differential rotation and the small-scale helical fluctuations due to supernova explosions. We report for the first time direct numerical simulations of the full galactic dynamo using an un-parametrized global approach. We argue that the scale of helicity injection is large enough to be directly resolved rather than parametrized. While the actual superbubble characteristics can only be approached, we show that numerical simulations yield magnetic structures which are close to both the observations and the previous parametrized mean field models. In particular, the quadrupolar symmetry and the spiraling properties of the field are reproduced. Moreover, our simulations show that the presence of a vertical inflow plays an essential role to increase the magnetic growth rate. This observation could indicate an important role of the downward flow (possibly linked with galactic fountains) in sustaining galactic magnetic fields.