SIMBAD references

We use statistical equilibrium equations to investigate the Infrared Array Camera (IRAC) color space of shocked molecular hydrogen. The location of shocked H₂ in [3.6] - [4.5] versus [4.5] - [5.8] color is determined by the gas temperature and density of neutral atomic hydrogen. We find that high excitation H₂ emission falls in a unique location in the color-color diagram and can unambiguously be distinguished from stellar sources. In addition to searching for outflows, we show that the IRAC data can be used to map the thermal structure of the shocked gas. We analyze archival Spitzer data of Herbig-Haro object HH 54 and create a temperature map, which is consistent with spectroscopically determined temperatures.