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ABSTRACT Bok globules are small, dense clouds that act as isolated precursors for the formation of single or binary stars. Although recent dust polarization surveys, primarily with Planck, have shown that molecular clouds are strongly magnetized, the significance of magnetic fields in Bok globules has largely been limited to individual case studies, lacking a broader statistical understanding. In this work, we introduce a comprehensive optical polarimetric survey of 21 Bok globules. Using Gaia and near-infrared (IR) photometric data, we produce extinction maps for each target. Using the radiative torque alignment model customized to the physical properties of the Bok globule, we characterize the polarization efficiency of one representative globule as a function of its visual extinction. We thus find our optical polarimetric data to be a good probe of the globule’s magnetic field. Our statistical analysis of the orientation of elongated extinction structures relative to the plane-of-sky magnetic field orientations shows they do not align strictly parallel or perpendicular. Instead, the data is best explained by a bimodal distribution, with structures oriented at projected angles that are either parallel or perpendicular. The plane-of-sky magnetic field strengths on the scales probed by optical polarimetric data are measured using the Davis–Chandrasekhar–Fermi technique. We then derive magnetic properties such as Alfvén Mach numbers and mass-to-magnetic flux ratios. Our findings statistically place the large-scale (A$$_{\mathrm{V}} < 7 \, \text{mag}$$) magnetic properties of Bok globules in a dynamically important domain. 

Abstract A compact source, G0.02467–0.0727, was detected in Atacama Large Millimeter/submillimeter Array 3 mm observations in continuum and very broad line emission. The continuum emission has a spectral indexα≈ 3.3, suggesting that the emission is from dust. The line emission is detected in several transitions of CS, SO, and SO₂and exhibits a line width FWHM ≈ 160 km s⁻¹. The line profile appears Gaussian. The emission is weakly spatially resolved, coming from an area on the sky ≲1″ in diameter (≲10⁴au at the distance of the Galactic center, GC). The centroid velocity isv_LSR≈ 40–50 km s⁻¹, which is consistent with a location in the GC. With multiple SO lines detected, and assuming local thermodynamic equilibrium (LTE) conditions, the gas temperature isT_LTE= 13 K, which is colder than seen in typical GC clouds, though we cannot rule out low-density, subthermally excited, warmer gas. Despite the high velocity dispersion, no emission is observed from SiO, suggesting that there are no strong (≳10 km s⁻¹) shocks in the molecular gas. There are no detections at other wavelengths, including X-ray, infrared, and radio. We consider several explanations for the millimeter ultra-broad-line object (MUBLO), including protostellar outflow, explosive outflow, a collapsing cloud, an evolved star, a stellar merger, a high-velocity compact cloud, an intermediate-mass black hole, and a background galaxy. Most of these conceptual models are either inconsistent with the data or do not fully explain them. The MUBLO is, at present, an observationally unique object.