Chemical Tracers of Pre-Brown Dwarf Cores Formed Through Turbulent
  Fragmentation
  A gas-grain time dependent chemical code, UCL\_CHEM, has been used to
investigate the possibility of using chemical tracers to differentiate between
the possible formation mechanisms of brown dwarfs. In this work, we model the
formation of a pre-brown dwarf core through turbulent fragmentation by
following the depth-dependent chemistry in a molecular cloud through the step
change in density associated with an isothermal shock and the subsequent
freefall collapse once a bound core is produced. Trends in the fractional
abundance of molecules commonly observed in star forming cores are then
explored to find a diagnostic for identifying brown dwarf mass cores formed
through turbulence. We find that the cores produced by our models would be
bright in CO and NH$_3$ but not in HCO$^+$. This differentiates them from
models using purely freefall collapse as such models produce cores that would
have detectable transitions from all three molecules.
