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An increasing number of observations and simulations suggests that low-power (< 1044 erg s−1) jets may be a significant channel of feedback produced by active galactic nuclei (AGN), but little is known about their actual effect on their host galaxies from the observational point of view. We targeted four luminous type 2 AGN hosting moderately powerful radio emission (∼1044 erg s−1), two of which and possibly a third are associated with jets, with optical integral field spectroscopy observations from the Multi Unit Spectroscopic Explorer (MUSE) at the Very Large Telescope (VLT) to analyze the properties of their ionized gas as well as the properties and effects of ionized outflows. We combined these observations with Very Large Array (VLA) and e-MERLIN data to investigate the relations and interactions between the radio jets and host galaxies. We detected ionized outflows as traced by the fast bulk motion of the gas. The outflows extended over kiloparsec scales in the direction of the jet, when present. In the two sources with resolved radio jets, we detected a strong enhancement in the emission-line velocity dispersion (up to 1000 km s−1) perpendicular to the direction of the radio jets. We also found a correlation between the mass and the energetics of this high-velocity dispersion gas and the radio power, which supports the idea that the radio emission may cause the enhanced turbulence. This phenomenon, which is now being observed in an increasing number of objects, might represent an important channel for AGN feedback on galaxies [ABSTRACT FROM AUTHOR]

Studying the feedback process of active galactic nuclei (AGN) requires the characterisation of multiple kinematical components, such as rotating gas and stellar discs, outflows, inflows, and jets. The usual approach to compare the observed galaxy properties with feedback theoretical predictions relies on simplified kinematic models. This allows us to assess the mutual interaction between the galaxy components and determine the energy injection rate into the interstellar medium. However, these models have several limitations, as they often do not take into account projection effects, beam smearing, or the surface brightness distribution of the emitting medium. Here, we present MOKA3D, an innovative approach to modelling the 3D gas kinematics from integral field spectroscopy observations. In this first paper, we discuss its application to the case of AGN ionised outflows, whose observed clumpy emission and apparently irregular kinematics are only marginally accounted for by the existing kinematical models. Unlike previous works, our model does not assume the surface brightness distribution of the gas, but exploits a novel procedure to derive it from observations by reconstructing the 3D distribution of emitting clouds and providing accurate estimates of the physical properties of spatially resolved outflow (e.g., mass rate, kinetic energy). We demonstrate the capabilities of our method by applying it to three nearby Seyfert-II galaxies observed with the Multi Unit Spectroscopic Explorer (MUSE) at the VLT and selected from the Measuring Active Galactic Nuclei Under MUSE Microscope (MAGNUM) survey, showing that the complex kinematic features observed can be described by a conical outflow with a constant radial velocity field and a clumpy distribution of clouds. [ABSTRACT FROM AUTHOR]

The diffuse Fe XXV (6.7 keV) line emission observed in the Galactic ridge is widely accepted to be produced by a superposition of a large number of unresolved X-ray point sources. In the very central degrees of our Galaxy, however, the existence of an extremely hot (~7 keV) diffuse plasma is still under debate. In this work we measure the Fe XXV line emission using all available XMM-Newton observations of the Galactic centre (GC) and inner disc (−10° < ℓ < 10°, −2° < b < 2°). We use recent stellar mass distribution models to estimate the amount of X-ray emission originating from unresolved point sources, and find that within a region of ℓ = ±1° and b = ±0.25° the 6.7keV emission is 1.3–1.5 times in excess of what is expected from unresolved point sources. The excess emission is enhanced towards regions where known supernova remnants are located, suggesting that at least a part of this emission is due to genuine diffuse very hot plasma. If the entire excess is due to very hot plasma, an energy injection rate of at least ~6 × 1040 erg s−1 is required, which cannot be provided by the measured supernova explosion rate or past Sgr A* activity alone. However, we find that almost the entire excess we observe can be explained by assuming GC stellar populations with iron abundances ~1.9 times higher than those in the bar/bulge, a value that can be reproduced by fitting diffuse X-ray spectra from the corresponding regions. Even in this case, a leftover X-ray excess is concentrated within ℓ = ±0.3° and b = ±0.15°, corresponding to a thermal energy of ~2 × 1052 erg, which can be reproduced by the estimated supernova explosion rate in the GC. Finally we discuss a possible connection to the observed GC Fermi-LAT excess. [ABSTRACT FROM AUTHOR]

We probe the star formation properties of the gas in AzTEC-1 in the COSMOS field, one of the best resolved and brightest starburst galaxies at z ≈ 4.3, forming stars at a rate |$\gt \, 1000\, {\mathrm{M}_{\odot}}\, \mathrm{yr^{-1}}$|⁠. Using recent ALMA observations, we study star formation in the galaxy nucleus and an off-centre star-forming clump and measure a median star formation rate (SFR) surface density of |$\Sigma ^{\mathrm{nucleus}}_{\mathrm{SFR}} = 270\pm 54$| and |$\Sigma ^{\mathrm{sfclump}}_{\mathrm{SFR}} = 170\pm 38\, {\mathrm{M}_{\odot}}\, \mathrm{yr}^{-1}\, \mathrm{kpc}^{-2}$|⁠ , respectively. Following the analysis by Sharda et al. (2018), we estimate the molecular gas mass, freefall time, and turbulent Mach number in these regions to predict ΣSFR from three star formation relations in the literature. The Kennicutt–Schmidt (Kennicutt 1998 ; KS) relation, which is based on the gas surface density, underestimates the ΣSFR in these regions by a factor 2–3. The ΣSFR we calculate from the single-freefall model of Krumholz et al. (2012 ; KDM) is consistent with the measured ΣSFR in the nucleus and the star-forming clump within the uncertainties. The turbulence-regulated star formation relation by Salim et al. (2015 ; SFK) agrees slightly better with the observations than the KDM relation. Our analysis reveals that an interplay between turbulence and gravity can help sustain high SFRs in high-redshift starbursts. It can also be extended to other high- and low-redshift galaxies thanks to the high-angular resolution and sensitivity of ALMA observations. [ABSTRACT FROM AUTHOR]

We use new high-resolution H  i data from the Australian Square Kilometre Array Pathfinder to investigate the dynamics of the Small Magellanic Cloud (SMC). We model the H  i gas component as a rotating disc of non-negligible angular size, moving into the plane of the sky, and undergoing nutation/precession motions. We derive a high-resolution (∼10 pc) rotation curve of the SMC out to |$R\sim 4 \, \, {\rm kpc}$|⁠. After correcting for asymmetric drift, the circular velocity slowly rises to a maximum value of |$V_\mathrm{c}\simeq 55 \, \, {\rm km\, s}^{-1}$| at |$R\simeq 2.8 \, \, {\rm kpc}$| and possibly flattens outwards. In spite of the SMC undergoing strong gravitational interactions with its neighbours, its H  i rotation curve is akin to that of many isolated gas-rich dwarf galaxies. We decompose the rotation curve and explore different dynamical models to deal with the unknown 3D shape of the mass components (gas, stars, and dark matter). We find that, for reasonable mass-to-light ratios, a dominant dark matter halo with mass |$M_\mathrm{DM}(R\lt 4 \, \, {\rm kpc}) \simeq 1\!-\!1.5 \times 10^9 \, {\rm M}_\odot$| is always required to successfully reproduce the observed rotation curve, implying a large baryon fraction of |$30{{\ \rm per\ cent}}\!-\!40{{\ \rm per\ cent}}$|⁠. We discuss the impact of our assumptions and the limitations of deriving the SMC kinematics and dynamics from H  i observations. [ABSTRACT FROM AUTHOR]

We investigate the relation between stellar mass (M⋆) and specific stellar angular momentum (j⋆), or "Fall relation", for a sample of 17 isolated, regularly rotating disc galaxies at z ∼ 1. All galaxies have rotation curves determined from Hα emission-line data; HST imaging in optical and infrared filters; and robust determinations of their stellar masses. We use HST images in f814w and f160w filters, roughly corresponding to rest-frames B and I bands, to extract surface-brightness profiles for our systems. We robustly bracket j⋆ by assuming that rotation curves beyond the outermost Hα rotation point stay either flat or follow a Keplerian fall-off. By comparing our measurements with those determined for disc galaxies in the local universe, we find no evolution in the Fall relation in the redshift range 0 <  z <  1, regardless of the band used and despite the uncertainties in the stellar rotation curves at large radii. This result holds unless stellar masses at z = 1 are systematically underestimated by ≳50%. Our findings are compatible with expectations based on a ΛCDM cosmological framework and support a scenario where both the stellar Tully–Fisher and mass-size relations for spirals do not evolve significantly in this redshift range. [ABSTRACT FROM AUTHOR]

We use Multi Unit Spectroscopic Explorer (MUSE) observations of the galaxy cluster MACS J1149.5+2223 to explore the kinematics of the grand-design spiral galaxy (Sp1149) hosting the supernova 'Refsdal'. Sp1149 lies at z ⋍ 1.49, has a stellar mass M* ⋍ 5 × 109M ⊙, has a star formation rate (SFR) ⋍ 1-6 M⊙ yr-1, and represents a likely progenitor of a Milky Way-like galaxy. All the four multiple images of Sp1149 in our data show strong [O II]-line emissions pointing to a clear rotation pattern. We take advantage of the gravitational lensing magnification effect (⋍4×) on the [OII] emission of the least distorted image to fit threedimensional kinematic models to the MUSE data cube and derive the rotation curve and the velocity dispersion profile of Sp1149. We find that the rotation curve steeply rises, peaks at R ⋍ 1 kpc, and then (initially) declines and flattens to an average Vflat = 128+29 -19 km s-1. The shape of the rotation curve is well determined, but the actual value of Vflat is quite uncertain because of the nearly face-on configuration of the galaxy. The intrinsic velocity dispersion due to gas turbulence is almost constant across the entire disc with an average of 27 ± 5 kms-1. This value is consistent with z = 0 measurements in the ionized gas component and a factor of 2-4 lower than other estimates in different galaxies at similar redshifts. The average stellarto- total mass fraction is of the order of one-fifth. Our kinematic analysis returns the picture of a regular star-forming, mildly turbulent, rotation-dominated (V/s ⋍ 5) spiral galaxy in a 4-Gyr-old Universe. [ABSTRACT FROM AUTHOR]

We quantify the gas accretion rate from minor mergers onto star-forming galaxies in the local Universe using Hi observations of 148 nearby spiral galaxies (WHISP sample). We developed a dedicated code that iteratively analyses Hi data-cubes, finds dwarf gas-rich satellites around larger galaxies, and estimates an upper limit to the gas accretion rate. We found that 22% of the galaxies have at least one detected dwarf companion. We made the very stringent assumption that all satellites are going to merge in the shortest possible time, transferring all their gas to the main galaxies. This leads to an estimate of the maximum gas accretion rate of 0.28 M⊙ yr-1, about five times lower than the average star formation rate of the sample. Given the assumptions, our accretion rate is clearly an overestimate. Our result strongly suggests that minor mergers do not play a significant role in the total gas accretion budget in local galaxies. [ABSTRACT FROM AUTHOR]