  I continue my study of the low-z Lyman alpha cloud population. Previously I
showed how galaxy catalogs are used to attribute relative degrees of isolation
to those clouds found in HST/GHRS spectra. I find that there exist two distinct
populations corresponding to two distinct environments, variously characterized
as void (unshocked) and non-void (shocked). Void clouds have a steep equivalent
width distribution (i.e., many smaller absorbers) while non-void clouds have a
flat distribution. These environment-specific observations of LyA clouds show
that the predictions from N-body/hydro simulations are incorrect. Simulations
fail to predict the existence of significant numbers of detectable void clouds.
They incorrectly predict the characteristics of non-void clouds. Implicated in
this failure is the so-called fluctuating Gunn-Peterson Approximation (FGPA)
which envisions that LyA absorbers are formed in the large-scale structures of
coalescing matter. I recently modeled the void cloud population as sub-galactic
perturbations that have expanded in response to reionization. However, the
success in this modeling was contingent upon using the more massive isothermal
halo in place of the standard Navarro, Frenk & White. Here, I extend my
modeling to non-void LyA clouds using the same basic cloud model. Nonvoid
clouds were once unshocked, but when entering nonvoid space, they are shock
stripped. By analytically stripping model void clouds, a good fit of the model
CDS to observations is found if cloud velocities are ~100 km/s. Nonvoid clouds
show strong concentration around galaxies, suggesting that the compact HVC
population are members of this population.
