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We present an overview and data release of the spectral line component of the SMA Large Program, CMZoom. CMZoom observed 12CO (2–1), 13CO (2–1), and C18O (2–1), three transitions of H2CO, several transitions of CH3OH, two transitions of OCS, and single transitions of SiO and SO within gas above a column density of N(H2) ≥ 1023 cm−2 in the Central Molecular Zone (CMZ; inner few hundred pc of the Galaxy). We extract spectra from all compact 1.3 mm CMZoom continuum sources and fit line profiles to the spectra. We use the fit results from the H2CO 3(0, 3)–2(0, 2) transition to determine the source kinematic properties. We find ∼90 per cent of the total mass of CMZoom sources have reliable kinematics. Only four compact continuum sources are formally self-gravitating. The remainder are consistent with being in hydrostatic equilibrium assuming that they are confined by the high external pressure in the CMZ. We find only two convincing proto-stellar outflows, ruling out a previously undetected population of very massive, actively accreting YSOs with strong outflows. Finally, despite having sufficient sensitivity and resolution to detect high-velocity compact clouds (HVCCs), which have been claimed as evidence for intermediate mass black holes interacting with molecular gas clouds, we find no such objects across the large survey area.

We report on the discovery of linear filaments observed in the CO(1-0) emission for a ∼2′ field of view toward the Sgr E star-forming region, centered at (l,b) = (358.°720, 0.°011). The Sgr E region is thought to be at the turbulent intersection of the “far dust lane” associated with the Galactic bar and the Central Molecular Zone (CMZ). This region is subject to strong accelerations, which are generally thought to inhibit star formation, yet Sgr E contains a large number of Hiiregions. We present¹²CO(1-0),¹³CO(1-0), and C¹⁸O(1-0) spectral line observations from the Atacama Large Millimeter/submillimeter Array and provide measurements of the physical and kinematic properties for two of the brightest filaments. These filaments have widths (FWHMs) of ∼0.1 pc and are oriented nearly parallel to the Galactic plane, with angles from the Galactic plane of ∼2°. The filaments are elongated, with lower-limit aspect ratios of ∼5:1. For both filaments, we detect two distinct velocity components that are separated by about 15 km s⁻¹. In the C¹⁸O spectral line data, with ∼0.09 pc spatial resolution, we find that these velocity components have relatively narrow (∼1–2 km s⁻¹) FWHM line widths when compared to other sources toward the Galactic center. The properties of these filaments suggest that the gas in the Sgr E complex is being “stretched,” as it is rapidly accelerated by the gravitational field of the Galactic bar while falling toward the CMZ, a result that could provide insights into the extreme environment surrounding this region and the large-scale processes that fuel this environment.