We investigate the prevalence , properties , and kinematics of extraplanar diffuse ionized gas ( eDIG ) in a sample of 25 edge-on galaxies selected from the CALIFA survey .
We measure ionized gas scale heights from H \alpha and find that 90 % have measurable scale heights with a median of 0.8 ^ { +0.7 } _ { -0.4 } kpc .
From the H \alpha kinematics , we find that 60 % of galaxies show a decrease in the rotation velocity as a function of height above the midplane .
This lag is characteristic of eDIG , and we measure a median lag of 21 km s ^ { -1 } kpc ^ { -1 } which is comparable to lags measured in the literature .
We also investigate variations in the lag with radius .
H I lags have been reported to systematically decrease with galactocentric radius .
We find both increasing and decreasing ionized gas lags with radius , as well as a large number of galaxies consistent with no radial lag variation , and investigate these results in the context of internal and external origins for the lagging ionized gas .
We confirm that the [ S II ] /H \alpha and [ N II ] /H \alpha line ratios increase with height above the midplane as is characteristic of eDIG .
The ionization of the eDIG is dominated by star-forming complexes ( leaky H II regions ) .
We conclude that the lagging ionized gas is turbulent ejected gas likely resulting from star formation activity in the disk as opposed to gas in the stellar thick disk or bulge .
This is further evidence for the eDIG being a product of stellar feedback and for the pervasiveness of this WIM-like phase in many local star-forming galaxies .