Modeling C-Shock Chemistry in Isolated Molecular Outflows
  Shocks are a crucial probe for understanding the ongoing chemistry within
ices on interstellar dust grains where many complex organic molecules (COMs)
are believed to be formed. However, previous work has been limited to the
initial liberation into the gas phase through non-thermal desorption processes
such as sputtering. Here, we present results from the adapted three-phase
gas-grain chemical network code NAUTILUS, with the inclusion of additional
high-temperature reactions, non-thermal desorption, collisional dust heating,
and shock-physics parameters. This enhanced model is capable of reproducing
many of the molecular distributions and abundance ratios seen in our prior
observations of the prototypical shocked-outflow L1157. In addition, we find
that, among others, NH$_2$CHO, HCOOCH$_3$, and CH$_3$CHO have significant
post-shock chemistry formation routes that differ from those of many other COMs
observed in shocks. Finally, a number of selected species and phenomena are
studied here with respect to their usefulness as shock tracers in various
astrophysical sources.
