  We continue our empirical study of the emission line flux originating in the
cool ($T\sim10^4$ K) gas that populates the halos of galaxies and their
environments. Specifically, we present results obtained for a sample of galaxy
pairs with a range of projected separations, {\bf $10 < {S_p/\rm kpc} < 200$},
and mass ratios $<$ 1:5, intersected by 5,443 SDSS lines of sight at projected
radii of 10 to 50 kpc from either or both of the two galaxies. We find
significant enhancement in H$\alpha$ emission and a moderate enhancement in [N
{\small II}]6583 emission for low mass pairs (mean stellar mass per galaxy,
$\overline{\rm M}_*, <10^{10.4} {\rm M}_\odot$) relative to the results from a
control sample. This enhanced H$\alpha$ emission comes almost entirely from
sight lines located between the galaxies, consistent with a short-term,
interaction-driven origin for the enhancement. We find no enhancement in
H$\alpha$ emission, but significant enhancement in [N {\small II}]6583 emission
for high mass ($\overline{\rm M}_* >10^{10.4}{\rm M}_\odot$) pairs.
Furthermore, we find a dependence of the emission line properties on the galaxy
pair mass ratio such that those with a mass ratio below 1:2.5 have enhanced [N
{\small II}]6583 and those with a mass ratio between 1:2.5 and 1:5 do not. In
all cases, departures from the control sample are only detected for close pairs
($S_p <$ 100 kpc). Attributing an elevated [N {\small II}]6583/H$\alpha$ ratio
to shocks, we infer that shocks play a role in determining the CGM properties
for close pairs that are among the more massive and have mass ratios closer to
1:1.
