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<jats:title>Abstract</jats:title> <jats:p>We present the highest-resolution—15 pc (0.″03)—ALMA <jats:sup>12</jats:sup>CO(2–1) line emission and 1.3 mm continuum maps, tracers of the molecular gas and dust, respectively, in the nearby merging galaxy system NGC 6240, which hosts two supermassive black holes growing simultaneously. These observations provide an excellent spatial match to existing <jats:italic>Hubble</jats:italic> <jats:italic>Space Telescope</jats:italic> (<jats:italic>HST</jats:italic>) optical and near-infrared observations of this system. A significant molecular gas mass, ∼9 × 10<jats:sup>9</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>, is located between the two nuclei, forming a clumpy stream kinematically dominated by turbulence, rather than a smooth rotating disk, as previously assumed from lower-resolution data. Evidence for rotation is seen in the gas surrounding the southern nucleus but not in the northern one. Dynamical shells can be seen, likely associated with nuclear supernova remnants. We further detect the presence of significant high-velocity outflows, some of them reaching velocities &gt;500 km s<jats:sup>−1</jats:sup>, affecting a significant fraction, ∼11%, of the molecular gas in the nuclear region. Inside the spheres of influence of the northern and southern supermassive black holes, we find molecular masses of 7.4 × 10<jats:sup>8</jats:sup> and 3.3 × 10<jats:sup>9</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>, respectively. We are thus directly imaging the reservoir of gas that can accrete onto each supermassive black hole. These new ALMA maps highlight the critical need for high-resolution observations of molecular gas in order to understand the feeding of supermassive black holes and its connection to galaxy evolution in the context of a major galaxy merger.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The Zeeman effect has been the only method to directly probe the magnetic field strength in molecular clouds. The Bayesian analysis of Zeeman measurements carried out by Crutcher et al. is the only reference for cloud magnetic field strength. Here we extended their model and Bayesian analysis of the relation between field strength (<jats:italic>B</jats:italic>) and volume density (<jats:italic>n</jats:italic>) in the following three directions based on the recent observational and theoretical development. First, we take <jats:italic>R</jats:italic>, the observational uncertainty of <jats:italic>n</jats:italic>, as a parameter to be estimated from data. Second, the restriction of <jats:italic>α</jats:italic>, the index of the <jats:italic>B</jats:italic>–<jats:italic>n</jats:italic> relationship, is relieved from [0, 0.75] to [0, 1]. Third, we allow <jats:italic>f</jats:italic>, the minimum-to-maximum <jats:italic>B</jats:italic> ratio, to vary with <jats:italic>n</jats:italic>. Our results show that taking <jats:italic>R</jats:italic> as a parameter provides a better fitting to the <jats:italic>B</jats:italic>–<jats:italic>n</jats:italic> relationship and much more reliable estimates on <jats:italic>R</jats:italic>, <jats:italic>f,</jats:italic> and the changing point of <jats:italic>α</jats:italic>. Arguably our most important finding is that <jats:italic>α</jats:italic> cannot be reliably estimated by any of the models studied here, either from us or Crutcher et al., if <jats:italic>R</jats:italic> &gt; 2, which is indeed the case from our estimate. This is the so-called errors-in-variables bias, a well known problem for statisticians.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We report the results of high-resolution molecular line observations of the high-velocity compact cloud HCN–0.085–0.094 with the Atacama Large Millimeter/submillimeter Array. The HCN <jats:italic>J</jats:italic> = 4–3, HCO<jats:sup>+</jats:sup> <jats:italic>J</jats:italic> = 4–3, and CS <jats:italic>J</jats:italic> = 7–6 line images reveal that HCN–0.085–0.094 consists mainly of three small clumps with extremely broad velocity widths. Each of the three clumps has a 5.5 GHz radio continuum counterpart in its periphery toward Sgr A*. The positional relationship indicates that their surfaces have been ionized by ultraviolet photons from young stars in the central cluster, suggesting the clumps are in close proximity to the Galactic nucleus. One of the three clumps has a ring-like structure with a very steep velocity gradient. This kinematical structure suggests an orbit around a point-like object with a mass of ∼10<jats:sup>4</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>. The absence of stellar counterparts indicates that the point-like object may be a quiescent black hole. This discovery adds another intermediate-mass black hole candidate in the central region of our Galaxy.</jats:p>