[en] NGC 4013 is a distinctly warped galaxy with evidence of disk–halo activity. Through deep H i observations and modeling we confirm that the H i disk is thin (central exponential scale height with an upper limit of 4″ or 280 pc), but flaring. We detect a vertical gradient in rotation velocity (lag), which shallows radially from a value of −35${}_{-<!--\; ???\; -->28}^{+7}$ km s⁻¹ kpc⁻¹ at 1.′4 (5.8 kpc), to a value of zero near R₂₅ (11.2 kpc). Over much of this radial range, the lag is relatively steep. Both the steepness and the radial shallowing are consistent with recent determinations for a number of edge-ons, which have been difficult to explain. We briefly consider the lag measured in NGC 4013 in the context of this larger sample and theoretical models, further illuminating disk–halo flows.

[en] We report the results of a search for large velocity width, low-intensity line wings—a commonly used signature of molecular outflows—in four low redshift (ultra)luminous infrared galaxies that appear to be dominated by star formation. The targets were drawn from a sample of fourteen targets presented in Chung et al., who showed the stacked CO spectrum of the sample to exhibit 1000 km s"−"1-wide line wings. We obtained sensitive, wide bandwidth imaging of our targets using the IRAM Plateau de Bure Interferometer. We detect each target at very high significance but do not find the claimed line wings in these four targets. Instead, we constrain the flux in the line wings to be only a few percent. Casting our results as mass outflow rates following Cicone et al. we show them to be consistent with a picture in which very high mass loading factors preferentially occur in systems with high active galactic nucleus contributions to their bolometric luminosity. We identify one of our targets, IRAS 05083 (VII Zw 31), as a candidate molecular outflow

[en] To further understand the origins of and physical processes operating in extra-planar gas, we present observations and kinematic models of H I in the two nearby, edge-on spiral galaxies NGC 3044 and NGC 4302. We model NGC 3044 as a single, thick disk. Substantial amounts of extra-planar H I are also detected. We detect a decrease in rotation speed with height (a lag) that shallows radially, reaching zero at approximately R ₂₅. The large-scale kinematic asymmetry of the approaching and receding halves suggests a recent disturbance. The kinematics and morphology of NGC 4302, a Virgo Cluster member, are greatly disturbed. We model NGC 4302 as a combination of a thin disk and a second, thicker disk, the latter having a hole near the center. We detect lagging extra-planar gas, with indications of shallowing in the receding half, although its characteristics are difficult to constrain. A bridge is detected between NGC 4302 and its companion, NGC 4298. We explore trends involving the extra-planar H I kinematics of these galaxies, as well as galaxies throughout the literature, as well as possible connections between lag properties with star formation and environment. Measured lags are found to be significantly steeper than those modeled by purely ballistic effects, indicating additional factors. Radial shallowing of extra-planar lags is typical and occurs between 0.5R ₂₅ and R ₂₅, suggesting internal processes are important in dictating extra-planar kinematics

[en] We observe Arp 220, the nearest ultra-luminous infrared galaxy, over 4 GHz in the K and Ka bands, providing constraints for the kinematics and morphology, and identifying molecular species on scales resolving both nuclei (0.″6 or 230 pc). We detect multiple molecular species, including hydroxyl (OH ${}^2{\mathrm{\Pi <!--\; ??\; -->}}_{3/2}J=9/2F=4-<!--\; ???\; -->4;5-<!--\; ???\; -->5$) in both cores, and tentatively detect H₂O(6₁₅-5₂₃) at ∼21.84 GHz in both nuclei, indicating the likely presence of maser emission. The observed frequency range also contains metastable ammonia transitions from (J, K) = (1, 1)–(5, 5), as well as the (9, 9) inversion line; together, they are a well-known thermometer of dense molecular gas. Furthermore, the non-metastable (4, 2) and (10, 9), and possibly the (3, 1), lines are also detected. We apply a standard temperature analysis to Arp 220; however, the analysis is complicated in that standard local thermal equilibrium (LTE) assumptions do not hold. There are indications that a substantial fraction of ammonia could be in the non-metastable transitions, as opposed to only the metastable ones. Thus, the non-metastable transitions could be essential to constraining the temperature. We compare all of these data to ALMA observations of this source, confirming the outflow previously observed by other tracers in both nuclei.

[en] We present 21 cm observations and models of the neutral hydrogen in NGC 4565, a nearby, edge-on spiral galaxy, as part of the Westerbork Hydrogen Accretion in LOcal GAlaxieS survey. These models provide insight concerning both the morphology and kinematics of H I above, as well as within, the disk. NGC 4565 exhibits a distinctly warped and asymmetric disk with a flaring layer. Our modeling provides no evidence for a massive, extended H I halo. We see evidence for a bar and associated radial motions. Additionally, there are indications of radial motions within the disk, possibly associated with a ring of higher density. We see a substantial decrease in rotational velocity with height above the plane of the disk (a lag) of –40⁺⁵_–20 km s^–1 kpc^–1 and –30⁺⁵_–30 km s^–1 kpc^–1 in the approaching and receding halves, respectively. This lag is only seen within the inner ∼4.'75 (14.9 kpc) on the approaching half and ∼4.'25 (13.4 kpc) on the receding half, making this a radially shallowing lag, which is now seen in the H I layers of several galaxies. When comparing results for NGC 4565 and those for other galaxies, there are tentative indications of high star formation rate per unit area being associated with the presence of a halo. Finally, H I is found in two companion galaxies, one of which is clearly interacting with NGC 4565.

[en] We present 21 cm observations and models of the H I kinematics and distribution of NGC 4244, a nearby edge-on Scd galaxy observed as part of the Westerbork HALOGAS (Hydrogen Accretion in LOcal GAlaxieS) survey. Our models give insight into the H I kinematics and distribution with an emphasis on the potential existence of extraplanar gas as well as a negative gradient in rotational velocity with height above the plane of the disk (a lag). Our models yield strong evidence against a significantly extended halo and instead favor a warp component along the line of sight as an explanation for most of the observed thickening of the disk. Based on these models, we detect a lag of -9⁺³_-2 km s^-1 kpc^-1 in the approaching half and -9 ± 2 km s^-1 kpc^-1 in the receding half. This lag decreases in magnitude to -5 ± 2 km s^-1 kpc^-1 and -4 ± 2 km s^-1 kpc^-1 near a radius of 10 kpc in the approaching and receding halves, respectively. Additionally, we detect several distinct morphological and kinematic features including a shell that is probably driven by star formation within the disk.

[en] We present ALMA detections of the [C ii] 158 μm emission line and the underlying far-infrared (FIR) continuum of three quasars at 6.6 < z < 6.9 selected from the VIKING survey. The [C ii] line fluxes range between 1.6 and 3.4 Jy km s⁻¹ ([C ii] luminosities ∼(1.9–3.9) × 10⁹ L_⊙). We measure continuum flux densities of 0.56–3.29 mJy around 158 μm (rest frame), with implied FIR luminosities of (0.6–7.5) × 10¹² L_⊙ and dust masses M_d = (0.7–24) × 10⁸ M_⊙. In one quasar we derive a dust temperature of ${30}_{-<!--\; ???\; -->9}^{+12}$ K from the continuum slope, below the canonical value of 47 K. Assuming that the [C ii] and continuum emission are powered by star formation, we find star formation rates from 100 to 1600 M_⊙ yr⁻¹ based on local scaling relations. The L_{[C ii]}/L_FIR ratios in the quasar hosts span a wide range from (0.3–4.6) × 10⁻³, including one quasar with a ratio that is consistent with local star-forming galaxies. We find that the strength of the L_{[C ii]} and 158 μm continuum emission in z ≳ 6 quasar hosts correlates with the quasar’s bolometric luminosity. In one quasar, the [C ii] line is significantly redshifted by ∼1700 km s⁻¹ with respect to the Mg ii broad emission line. Comparing to values in the literature, we find that, on average, the Mg ii is blueshifted by 480 km s⁻¹ (with a standard deviation of 630 km s⁻¹) with respect to the host galaxy redshift, i.e., one of our quasars is an extreme outlier. Through modeling we can rule out a flat rotation curve for our brightest [C ii] emitter. Finally, we find that the ratio of black hole mass to host galaxy (dynamical) mass is higher by a factor of 3–4 (with significant scatter) than local relations.

[en] We present ALMA observations of the inner 1′ (1.2 kpc) of the Circinus galaxy, the nearest Seyfert. We target CO (1–0) in the region associated with a well-known multiphase outflow driven by the central active galactic nucleus (AGN). While the geometry of Circinus and its outflow make disentangling the latter difficult, we see indications of outflowing molecular gas at velocities consistent with the ionized outflow. We constrain the mass of the outflowing molecular gas to be 1.5 × 10⁵−5.1 × 10⁶ M _⊙, yielding a molecular outflow rate of 0.35–12.3 M _⊙ yr⁻¹. The values within this range are comparable to the star formation (SF) rate in Circinus, indicating that the outflow indeed regulates SF to some degree. The molecular outflow in Circinus is considerably lower in mass and energetics than previously studied AGN-driven outflows, especially given its high ratio of AGN luminosity to bolometric luminosity. The molecular outflow in Circinus is, however, consistent with some trends put forth by Cicone et al., including a linear relation between kinetic power and AGN luminosity, as well as its momentum rate versus bolometric luminosity (although the latter places Circinus among the starburst galaxies in that sample). We detect additional molecular species including CN and C¹⁷O.

[en] We present spatially resolved (∼50 pc) imaging of molecular gas species in the central kiloparsec of the nearby starburst galaxy NGC 253, based on observations taken with the Atacama Large Millimeter/submillimeter Array. A total of 50 molecular lines are detected over a 13 GHz bandwidth imaged in the 3 mm band. Unambiguous identifications are assigned for 27 lines. Based on the measured high CO/C"1"7O isotopic line ratio (≳350), we show that "1"2CO(1-0) has moderate optical depths. A comparison of the HCN and HCO"+ with their "1"3C-substituted isotopologues shows that the HCN(1-0) and HCO"+(1-0) lines have optical depths at least comparable to CO(1-0). H"1"3CN/H"1"3CO"+ (and H"1"3CN/HN"1"3C) line ratios provide tighter constraints on dense gas properties in this starburst. SiO has elevated abundances across the nucleus. HNCO has the most distinctive morphology of all the bright lines, with its global luminosity dominated by the outer parts of the central region. The dramatic variation seen in the HNCO/SiO line ratio suggests that some of the chemical signatures of shocked gas are being erased in the presence of dominating central radiation fields (traced by C_2H and CN). High density molecular gas tracers (including HCN, HCO"+, and CN) are detected at the base of the molecular outflow. We also detect hydrogen β recombination lines that, like their α counterparts, show compact, centrally peaked morphologies, distinct from the molecular gas tracers. A number of sulfur based species are mapped (CS, SO, NS, C_2S, H_2CS, and CH_3SH) and have morphologies similar to SiO

[en] We present a detailed study of a molecular outflow feature in the nearby starburst galaxy NGC 253 using ALMA. We find that this feature is clearly associated with the edge of NGC 253's prominent ionized outflow, has a projected length of ∼300 pc, with a width of ∼50 pc, and a velocity dispersion of ∼40 km s⁻¹, which is consistent with an ejection from the disk about 1 Myr ago. The kinematics of the molecular gas in this feature can be interpreted (albeit not uniquely) as accelerating at a rate of 1 km s⁻¹ pc⁻¹. In this scenario, the gas is approaching an escape velocity at the last measured point. Strikingly, bright tracers of dense molecular gas (HCN, CN, HCO⁺, CS) are also detected in the molecular outflow: we measure an HCN(1–0)/CO(1–0) line ratio of $\sim <!--\; ???\; -->1/10$ in the outflow, similar to that in the central starburst region of NGC 253 and other starburst galaxies. By contrast, the HCN/CO line ratio in the NGC 253 disk is significantly lower ($\sim <!--\; ???\; -->1/30$), similar to other nearby galaxy disks. This strongly suggests that the streamer gas originates from the starburst, and that its physical state does not change significantly over timescales of ∼1 Myr during its entrainment in the outflow. Simple calculations indicate that radiation pressure is not the main mechanism for driving the outflow. The presence of such dense material in molecular outflows needs to be accounted for in simulations of galactic outflows.