The halo of M105 and its group environment as traced by planetary nebula
  populations: II. Using kinematics of single stars to unveil the presence of
  intragroup light around the Leo I galaxies NGC 3384 and M105
  M105 is an early-type galaxy in the nearby Leo I group, the closest galaxy
group to contain all galaxy types and therefore an excellent environment to
explore the low-mass end of intra-group light (IGL) assembly. We present a new
extended kinematic survey of planetary nebulae (PNe) in M105 and the
surrounding 30'x30' in the Leo I group with the Planetary Nebula Spectrograph.
We use PNe as kinematic tracers of the diffuse stellar light in the halo and
IGL and employ Gaussian mixture models to separate contributions from the
companion galaxy NGC 3384 and associate PNe with halo and IGL components around
M105. We present a catalogue of 314 PNe and firmly associate 93 with NGC 3384
and 169 with M105. The PNe in M105 are further associated with its halo and the
surrounding exponential envelope. We construct smooth velocity and velocity
dispersion fields and calculate projected rotation, velocity dispersion, and
$\lambda_R$ profiles for each component. Halo PNe exhibit declining velocity
dispersion and rotation profiles, while the velocity dispersion and rotation of
the exponential envelope increase notably at large radii. We identify three
regimes with distinct kinematics that are linked to distinct stellar population
properties: (i) the rotating core (within $1~R_\mathrm{eff}$) formed in situ
and dominated by metal-rich ([M/H]~0) stars likely formed in situ, (ii) the
halo from 1 to $7.5~R_\mathrm{eff}$ consisting of intermediate-metallicity
stars ([M/H]>-1), either formed in situ or brought in through major mergers,
and (iii) the exponential envelope reaching beyond our farthest data point at
16 $R_\mathrm{eff}$, predominately composed of metal-poor ([M/H]<-1) stars. The
high velocity dispersion and moderate rotation of the latter are consistent
with that measured for dwarf satellite galaxies in the Leo I group, indicating
that the exponential envelope traces the transition to the IGL.
