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<jats:title>Abstract</jats:title> <jats:p>Spatially resolved velocity maps at high resolutions of 1–10 pc are becoming available for many nearby active galactic nuclei (AGNs) in both optical/infrared atomic emission lines and submillimeter molecular lines. For the former, it is known that a linear relationship appears to exist between the velocity of the ionized gas clouds and the distance from the nucleus in the inner ∼100 pc region, where these clouds are outflowing. Here we demonstrate that, in such a case, we can actually derive the three-dimensional (3D) geometrical distribution of the clouds directly from the velocity map. Revisiting such a velocity map taken by the Hubble Space Telescope for the prototypical Type 2 AGN NGC 1068, we implement the visualization of the 3D distribution derived from the map, and show that this inner narrow-line region has indeed a hollow-cone structure, consistent with previous modeling results. Quite possibly, this is the outer extended part of the polar elongated dusty material seen in the recent mid-infrared interferometry at parsec scale. Conversely, the latter small-scale geometry is inferred to have a hollow-cone outflowing structure as the inward extension of the derived 3D distribution above. The AGN obscuring “torus” is argued to be the inner optically thick part of this hollow-cone outflow, and its shadowed side would probably be associated with the molecular outflow seen in certain submillimeter lines. We discuss the nature of the linear velocity field, which could be from an episodic acceleration that occurred ∼10<jats:sup>5</jats:sup> yr ago.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We study the association between active galactic nuclei (AGNs) and environment at scales of 0.01–1 <jats:inline-formula> <jats:tex-math> <?CDATA ${h}^{-1}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>h</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc1e6ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> Mpc in the <jats:monospace>IllustrisTNG</jats:monospace> simulated universe (<jats:monospace>TNG100</jats:monospace>). We identify supermassive black hole (BH) pairs and multiples within scales of 0.01, 0.1, and 1 <jats:inline-formula> <jats:tex-math> <?CDATA ${h}^{-1}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>h</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc1e6ieqn2.gif" xlink:type="simple" /> </jats:inline-formula> Mpc and examine their AGN activity in relation to randomly selected pairs and multiples. The number density of BHs in <jats:monospace>TNG100</jats:monospace> is <jats:italic>n</jats:italic> = 0.06 <jats:italic>h</jats:italic> <jats:sup>3</jats:sup> Mpc<jats:sup>−3</jats:sup> at <jats:italic>z</jats:italic> ≲ 1.5 (<jats:italic>n</jats:italic> = 0.02 <jats:italic>h</jats:italic> <jats:sup>3</jats:sup> Mpc<jats:sup>−3</jats:sup> at <jats:italic>z</jats:italic> = 3). About ∼10% and ∼1% of these BHs live in pairs and multiples, respectively, within 0.1 <jats:inline-formula> <jats:tex-math> <?CDATA ${h}^{-1}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>h</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc1e6ieqn3.gif" xlink:type="simple" /> </jats:inline-formula> Mpc scales. These systems have enhanced likelihood (up to factors of 3–6) of containing high Eddington ratio (<jats:italic>η</jats:italic> ≳ 0.7) AGNs compared to random pairs and multiples. Conversely, the likelihood of an AGN to live in 0.1 <jats:inline-formula> <jats:tex-math> <?CDATA ${h}^{-1}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>h</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc1e6ieqn4.gif" xlink:type="simple" /> </jats:inline-formula> Mpc scale BH systems is also higher (by factors ∼4 for <jats:italic>η</jats:italic> ≳ 0.7) compared to random pairs and multiples. ∼10% of ultra-hard X-ray selected AGNs in <jats:monospace>TNG100</jats:monospace> have detectable 2–10 keV AGN companions on 0.1 <jats:inline-formula> <jats:tex-math> <?CDATA ${h}^{-1}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>h</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc1e6ieqn5.gif" xlink:type="simple" /> </jats:inline-formula> Mpc scales, consistent with observations. On larger spatial scales (∼1 <jats:inline-formula> <jats:tex-math> <?CDATA ${h}^{-1}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>h</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc1e6ieqn6.gif" xlink:type="simple" /> </jats:inline-formula> Mpc), however, no significant enhancements in AGN activity exist, even at high Eddington ratios. This implies that small-scale (≲0.1 <jats:inline-formula> <jats:tex-math> <?CDATA ${h}^{-1}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>h</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc1e6ieqn7.gif" xlink:type="simple" /> </jats:inline-formula> Mpc) AGN enhancement is likely driven by galaxy interactions and mergers. Nonetheless, the overall percentage of AGNs living in ≲0.1 <jats:inline-formula> <jats:tex-math> <?CDATA ${h}^{-1}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>h</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc1e6ieqn8.gif" xlink:type="simple" /> </jats:inline-formula> Mpc scale multiples is still subdominant (≲40%). Furthermore, the associated Eddington ratio enhancements of BH systems (as well as merging BHs) is only up to factors of ∼2–3. Our results support the existence of merger-AGN connection in <jats:monospace>TNG100</jats:monospace>. However, it plays a relatively minor role in fueling the AGN population.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The idea that mergers are more likely in dense groups or clusters coupled with the assumption that such events lead to cold gas flows onto black holes suggests a direct relationship between the radiative efficiency of an active galactic nucleus and environmental richness. Observations, however, increasingly challenge this and other basic expectations. Mounting evidence, for example, shows an inverse trend between near-Eddington accreting objects and environmental richness. Broken down by radio galaxy subgroup, recent work has explored connections between low excitation radio galaxies with Fanaroff–Riley II jet morphology (FR II LERGs) and other radio galaxies. We make contact with that work by adding a discussion of the recently discovered FR0 radio galaxies and show how to fit them in a picture in which FRII LERGs are not initial or final phases in the lifetime of a radio galaxy, but de facto transition states. We describe how to understand the observed X-ray luminosity/cluster richness relation as a fundamental correlation to the nature of the jet–disk connection.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Exoplanet systems with multiple planets in mean motion resonances have often been hailed as a signpost of disk-driven migration. Resonant chains like Kepler-223 and Kepler-80 consist of a trio of planets with the three-body resonant angle librating and/or with a two-body resonant angle librating for each pair. Here we investigate whether close-in super-Earths and mini-Neptunes forming in situ can lock into resonant chains due to dissipation from a depleted gas disk. We simulate the giant impact phase of planet formation, including eccentricity damping from a gaseous disk, followed by subsequent dynamical evolution over tens of millions of years. In a fraction of simulated systems, we find that planets naturally lock into resonant chains. These planets achieve a chain of near-integer period ratios during the gas-disk stage, experience eccentricity damping that captures them into resonance, stay in resonance as the gas disk dissipates, and avoid subsequent giant impacts, eccentricity excitation, and chaotic diffusion that would dislodge the planets from resonance. Disk conditions that enable planets to complete their formation during the gas-disk stage enable those planets to achieve tight period ratios ≤2 and, if they happen to be near-integer period ratios, lock into resonance. Using the weighting of different disk conditions deduced by MacDonald et al. and forward modeling Kepler selection effects, we find that our simulations of in situ formation via oligarchic growth lead to a rate of observable trios with integer period ratios and librating resonant angles comparable to observed Kepler systems.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The optical and near-infrared (OIR) polarization of starlight is typically understood to arise from the dichroic extinction of that light by dust grains whose axes are aligned with respect to a local magnetic field. The size distribution of the aligned-grain population can be constrained by measurements of the wavelength dependence of the polarization. The leading physical model for producing the alignment is that of radiative alignment torques (RATs), which predicts that the most efficiently aligned grains are those with sizes larger than the wavelengths of light composing the local radiation field. Therefore, for a given grain-size distribution, the wavelength at which the polarization reaches a maximum (<jats:inline-formula> <jats:tex-math> <?CDATA ${\lambda }_{\max }$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc6b0ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>) should correlate with the characteristic reddening along the line of sight between the dust grains and the illumination source. A correlation between <jats:inline-formula> <jats:tex-math> <?CDATA ${\lambda }_{\max }$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc6b0ieqn2.gif" xlink:type="simple" /> </jats:inline-formula> and reddening has been previously established for extinctions up to <jats:inline-formula> <jats:tex-math> <?CDATA ${A}_{V}\approx 4$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc6b0ieqn3.gif" xlink:type="simple" /> </jats:inline-formula> mag. We extend the study of this relationship to a larger sample of stars in the Taurus cloud complex, including extinctions <jats:inline-formula> <jats:tex-math> <?CDATA ${A}_{V}\gt 10$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc6b0ieqn4.gif" xlink:type="simple" /> </jats:inline-formula> mag. We confirm the earlier results for <jats:inline-formula> <jats:tex-math> <?CDATA ${A}_{V}\lt 4$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc6b0ieqn5.gif" xlink:type="simple" /> </jats:inline-formula> mag but find that the <jats:inline-formula> <jats:tex-math> <?CDATA ${\lambda }_{\max }$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc6b0ieqn6.gif" xlink:type="simple" /> </jats:inline-formula> versus <jats:italic>A</jats:italic> <jats:sub> <jats:italic>V</jats:italic> </jats:sub> relationship bifurcates above <jats:inline-formula> <jats:tex-math> <?CDATA ${A}_{V}\approx 4$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc6b0ieqn7.gif" xlink:type="simple" /> </jats:inline-formula> mag, with part of the sample continuing the previously observed relationship. The remaining sample exhibits a steeper rise in <jats:inline-formula> <jats:tex-math> <?CDATA ${\lambda }_{\max }$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabc6b0ieqn8.gif" xlink:type="simple" /> </jats:inline-formula> versus <jats:italic>A</jats:italic> <jats:sub> <jats:italic>V</jats:italic> </jats:sub>. We propose that the data exhibiting the steep rise represent lines of sight of high-density “clumps,” where grain coagulation has taken place. We present RAT-based modeling supporting these hypotheses. These results indicate that multiband OIR polarimetry is a powerful tool for tracing grain growth in molecular clouds, independent of uncertainties in the dust temperature and emissivity.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present <jats:sup>29</jats:sup>SiO(<jats:italic>J</jats:italic> = 8–7) <jats:italic>ν</jats:italic> = 0, SiS (<jats:italic>J</jats:italic> = 19–18) <jats:italic>ν</jats:italic> = 0, and <jats:sup>28</jats:sup>SiO (<jats:italic>J</jats:italic> = 8–7) <jats:italic>ν</jats:italic> = 1 molecular line archive observations made with the Atacama Large Millimeter/Submillimeter Array (ALMA) of the molecular outflow associated with Orion Source I. The observations show velocity asymmetries about the flow axis that are interpreted as outflow rotation. We find that the rotation velocity (∼4–8 km s<jats:sup>−1</jats:sup>) decreases with the vertical distance to the disk. In contrast, the cylindrical radius (∼100–300 au), the expansion velocity (∼2–15 km s<jats:sup>−1</jats:sup>), and the axial velocity <jats:italic>v</jats:italic> <jats:sub>z</jats:sub> (∼−1–10 km s<jats:sup>−1</jats:sup>) increase with the vertical distance. The mass estimated of the molecular outflow <jats:italic>M</jats:italic> <jats:sub>outflow</jats:sub> ∼ 0.66–1.3 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub>. Given a kinematic time ∼130 yr, this implies a mass-loss rate <jats:inline-formula> <jats:tex-math> <?CDATA ${\dot{M}}_{\mathrm{outflow}}\sim 5.1-10\times {10}^{-3}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjabbe24ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> yr<jats:sup>−1</jats:sup>. This massive outflow sets important constraints on disk wind models. We compare the observations with a model of a shell produced by the interaction between an anisotropic stellar wind and an Ulrich accretion flow that corresponds to a rotating molecular envelope in collapse. We find that the model cylindrical radii are consistent with the <jats:sup>29</jats:sup>SiO(<jats:italic>J</jats:italic> = 8–7) <jats:italic>ν</jats:italic> = 0 data. The expansion velocities and the axial velocities of the model are similar to the observed values, except for the expansion velocity close to the disk (<jats:italic>z</jats:italic> ∼ ±150 au). Nevertheless, the rotation velocities of the model are a factor ∼3–10 lower than the observed values. We conclude that the Ulrich flow alone cannot explain the rotation observed and other possibilities should be explored, like the inclusion of the angular momentum of a disk wind.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Linear time series analysis, mainly the Fourier transform-based methods, has been quite successful in extracting information contained in the ever-modulating light curves of active galactic nuclei, and thereby contribute in characterizing the general features of supermassive black hole systems. In particular, the statistical properties of <jats:italic>γ</jats:italic>-ray variability of blazars are found to be fairly represented by flicker noise in the temporal frequency domain. However, these conventional methods have not been able to fully encapsulate the richness and the complexity displayed in the light curves of the sources. In this work, to complement our previous study on a similar topic, we perform nonlinear time series analysis of the decade-long Fermi/LAT observations of 20 <jats:italic>γ</jats:italic>-ray bright blazars. The study is motivated to address one of the most relevant queries: whether the dominant dynamical processes leading to the observed <jats:italic>γ</jats:italic>-ray variability are of deterministic or stochastic nature. For the purpose, we perform recurrence quantification analysis of the blazars and directly measure the quantities, which suggest that the dynamical processes in blazars could be a combination of deterministic and stochastic processes, while some of the source light curves revealed significant deterministic content. The result, with possible implication of strong disk-jet connection in blazars, could prove to be significantly useful in constructing models that can explain the rich and complex multiwavelength observational features in active galactic nuclei. In addition, we estimate the dynamical timescales, so-called trapping timescales, in the order of a few weeks.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We present ALMA (0.87 and 1.3 mm) and VLA (9 mm) observations toward the candidate intermediate-mass protostar OMC2-FIR3 (HOPS-370; <jats:italic>L</jats:italic> <jats:sub>bol</jats:sub> ∼ 314 <jats:italic>L</jats:italic> <jats:sub>⊙</jats:sub>) at ∼01 (40 au) resolution for the continuum emission and ∼025 (100 au) resolution of nine molecular lines. The dust continuum observed with ALMA at 0.87 and 1.3 mm resolves a near edge-on disk toward HOPS-370 with an apparent radius of ∼100 au. The VLA observations detect both the disk in dust continuum and free–free emission extended along the jet direction. The ALMA observations of molecular lines (H<jats:sub>2</jats:sub>CO, SO, CH<jats:sub>3</jats:sub>OH, <jats:sup>13</jats:sup>CO, C<jats:sup>18</jats:sup>O, NS, and H<jats:sup>13</jats:sup>CN) reveal rotation of the apparent disk surrounding HOPS-370 orthogonal to the jet/outflow direction. We fit radiative transfer models to both the dust continuum structure of the disk and molecular line kinematics of the inner envelope and disk for the H<jats:sub>2</jats:sub>CO, CH<jats:sub>3</jats:sub>OH, NS, and SO lines. The central protostar mass is determined to be ∼2.5 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> with a disk radius of ∼94 au, when fit using combinations of the H<jats:sub>2</jats:sub>CO, CH<jats:sub>3</jats:sub>OH, NS, and SO lines, consistent with an intermediate-mass protostar. Modeling of the dust continuum and spectral energy distribution yields a disk mass of 0.035 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> (inferred dust+gas) and a dust disk radius of 62 au; thus, the dust disk may have a smaller radius than the gas disk, similar to Class II disks. In order to explain the observed luminosity with the measured protostar mass, HOPS-370 must be accreting at a rate of (1.7−3.2) × 10<jats:sup>−5</jats:sup> <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> yr<jats:sup>−1</jats:sup>.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Based on a 3D supernova simulation of an 11.8 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> progenitor model with an initial solar composition, we study the nucleosynthesis using tracers covering the innermost 0.1 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> of the ejecta. These ejecta are mostly proton-rich and contribute significant amounts of <jats:sup>45</jats:sup>Sc and <jats:sup>64</jats:sup>Zn. The production of heavier isotopes is sensitive to the electron fraction and hence the neutrino emission from the proto-neutron star. The yields of these isotopes are rather uncertain due to the approximate neutrino transport used in the simulation. In order to obtain the total yields for the whole supernova, we combine the results from the tracers with those for the outer layers from a suitable 1D model. Using the yields of short-lived radionuclides (SLRs), we explore the possibility that an 11.8 <jats:italic>M</jats:italic> <jats:sub>⊙</jats:sub> supernova might have triggered the formation of the solar system and provided some of the SLRs measured in meteorites. In particular, we discuss two new scenarios that can account for at least the data on <jats:sup>41</jats:sup>Ca, <jats:sup>53</jats:sup>Mn, and <jats:sup>60</jats:sup>Fe without exceeding those on the other SLRs.</jats:p>