Planetary nebulae in NGC3379 and NGC3384

The PNe in M105 are further associated with its halo (138) and the surrounding exponential envelope (31). We also construct smooth velocity and velocity dispersion fields and calculate projected rotation, velocity dispersion, and {lambda}_R_ profiles for the different components. PNe associated with the halo exhibit declining velocity dispersion and rotation profiles as a function of radius, while the velocity dispersion and rotation of the exponential envelope increase notably at large radii.

The rotation axes of these different components are strongly misaligned. Based on the kinematic profiles, we identify three regimes with distinct kinematics that are also linked to distinct stellar population properties: (i) the rotating core at the centre of the galaxy (within 1~Reff) formed in situ and is dominated by metal-rich ([M/H]~0) stars that also likely formed in situ, (ii) the halo from 1 to 7.5Reff consisting of a mixture of intermediate-metallicity and metal-rich stars ([M/H]>-1), either formed in situ or was brought in via major mergers, and (iii) the exponential envelope reaching beyond our farthest data point at 16 Reff, predominately composed of metal-poor ([M/H]<-1) stars.

The high velocity dispersion and moderate rotation of the latter are consistent with those measured for the dwarf satellite galaxies in the Leo I group, indicating that this exponential envelope traces the transition to the IGL.