In this paper we present computations of the integrated metal-ion column densities produced in the post-shock cooling layers behind fast , radiative shock-waves .
For this purpose , we have constructed a new shock code that calculates the non-equilibrium ionization and cooling ; follows the radiative transfer of the shock self-radiation through the post-shock cooling layers ; takes into account the resulting photoionization and heating rates ; follows the dynamics of the cooling gas ; and self-consistently computes the initial photoionization state of the precursor gas .
We discuss the shock structure and emitted radiation , and study the dependence on the shock velocity , magnetic field , and gas metallicity .
We present a complete set of integrated post-shock and precursor metal-ion column densities of all ionization stages of the elements H , He , C , N , O , Ne , Mg , Si , S , and Fe , for shocks with velocities of 600 and \sim 2000 km s ^ { -1 } , corresponding to initial post-shock temperatures of 5 \times 10 ^ { 6 } and 5 \times 10 ^ { 7 } K , cooling down to 1000 K. We consider shocks in which the magnetic field is negligible ( B = 0 ) so that the cooling occurs at approximately constant pressure ( “ isobaric ” ) , and shocks in which the magnetic pressure dominates everywhere such that the cooling occurs at constant density ( isochoric ) .
We present results for gas metallicities Z ranging from 10 ^ { -3 } to twice the solar abundance of heavy elements , and we study how the observational signatures of fast radiative shocks depend on Z .
We present our numerical results in convenient online figures and tables .