2013ApJS..206...20A

We present 10 µm-35 µm Spitzer spectra of the interstellar medium in the Central Molecular Zone (CMZ), the central 210 pcx60 pc of the Galactic center (GC). We present maps of the CMZ in ionic and H₂emission, covering a more extensive area than earlier spectroscopic surveys in this region. The radial velocities and intensities of ionic lines and H₂ suggest that most of the H₂0-0 S(0) emission comes from gas along the line-of-sight, as found by previous work. We compare diagnostic line ratios measured in the Spitzer Infrared Nearby Galaxies Survey to our data. Previous work shows that forbidden line ratios can distinguish star-forming galaxies from low-ionization nuclear emission-line regions (LINERs) and active galactic nuclei (AGNs). Our GC line ratios agree with star-forming galaxies and not with LINERs or AGNs.