The vertical structure of the galactic gaseous disk and its relation to the dynamo problem

Galaxy-wide lower limits for the alpha- and eta-coefficients of the turbulent EMF have been obtained combining the empirically found global density distribution of interstellar matter with that minimal turbulent pressure necessary to prevent onset of Parker instability (cf. Bloemen 1987). The criterion used is that delineated by Lachieze-Rey et al. (1980). Upper limits for alpha and eta result from identifying the total internal pressure, following the assumption of hydrostatical equilibrium. The correlation time, tau(corr), scale like the local hydrostatic time-scale.