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We investigate the formation of hot coronae and vertical outflows inaccretion disks by magneto-rotational turbulence. We perform localthree-dimensional (3D) MHD simulations with the vertical stratification byexplicitly solving an energy equation with various effective ratios of specificheats, gamma. Initially imposed weak vertical magnetic fields are effectivelyamplified by magnetorotational instability (MRI) and winding due to thedifferential rotation. In the isothermal case (gamma=1), the disk winds aremainly driven by the Poynting flux associated with the MHD turbulence and showquasi-periodic intermittency. On the other hand, in the non-isothermal caseswith gamma >~ 1.1, the regions above 1-2 scale heights from the midplane areeffectively heated up to form coronae with the temperature of ~ 50 times of theinitial value, which are connected to the cooler midplane region through thepressure-balanced transition regions. As a result, the disk winds are mainlydriven by the gas pressure with exhibiting more time-steady nature, althoughthe nondimensional time-averaged mass loss rates are similar to that of theisothermal case. Sound-like waves are confined in the cool midplane region inthese cases, and the amplitude of the density fluctuations is larger than thatof the isothermal case.

Driving Disk Winds and Heating up Hot Coronae by MRI Turbulence