The Central Molecular Zone (CMZ) of the Galactic Center has to date only been fully mapped at mm wavelengths with singledish telescopes, with resolution about "30"(1.2 pc). Using CARMA, we mapped the innermost 0.25 square degrees of the CMZ over the region between -0°2≤ l ≤0°.5 and -0°.2≤b ≤0°.2 (90×50 pc) with spatial and spectral resolution of ∼ 10 (0.4 pc) and ∼ 2:5 km s-1, respectively. We provide a catalog of 3 mm continuum sources as well as spectral line images of SiO(J=2-1), HCO+(J=1-0), HCN(J=1-0), N2H+(J=1-0), and CS(J=2-1), with velocity coverage VLSR= -200 to 200 km s-1. To recover the large scale structure resolved out by the interferometer, the continuum-subtracted spectral line images were combined with data from the Mopra 22-m telescope survey, thus providing maps containing all spatial frequencies down to the resolution limit. We find that integrated intensity ratio of I(HCN)/I(HCO+) is anti-correlated with the intensity of the 6.4 keV Fe Kα, which is excited either by high energy photons or low energy cosmic rays, and the gas velocity dispersion as traced by HCO+ is correlated with Fe Kα intensity. The intensity ratio and velocity dispersion patterns are consistent with variation expected from the interaction of low energy cosmic rays with molecular gas.
|Original language||English (US)|
|State||Published - Sep 27 2017|
- Centre - ISM
- Clouds, dust - techniques
ASJC Scopus subject areas