An ATCA survey of Sagittarius B2 at 7 mm: chemical complexity meets broad-band interferometry

摘要: We present a 30 - 50 GHz survey of Sagittarius B2(N) conducted with the Australia Telescope Compact Array (ATCA) 5 10 arcsec resolution. This work releases data and demonstrates utility scripts that perform automated spectral line fitting on broadband data. describe line-fitting procedure, evaluate performance method, provide access to all scripts. The are used characterize spectra at positions three HII regions, each recombination emission molecular absorption. Towards most line-dense regions characterised in this work, we detect ~500 components which ~90 per cent confidently assigned H He lines 53 species their isotopologues. The reveal extremely subthermally excited gas absorbing against continuum background two primary velocity components. Based radiation over full spectra, abundances excitation appear vary substantially towards different positions, possibly indicating clouds located proximate star forming cores instead within envelope Sgr B2. Furthermore, spatial distributions including CS, OCS, SiO, HNCO indicate likely have high UV-flux. Finally, contain line-of-sight absorption by $\sim$15 molecules observed translucent Galactic Center, bar, intervening spiral arm clouds, revealing complex chemistry clumpy structure gas. Formamide (NH$_2$CHO) is detected for first time cloud.