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An increasing number of observations and simulations suggests that low-power (<10$^{44}$ 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 ($\sim$10$^{44}$ 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., Comment: 18 pages, 17 figures

We present HOMERUN (Highly Optimized Multi-cloud Emission-line Ratios Using photo-ionizatioN), a new approach to modelling emission lines from photoionized gas that can simultaneously reproduce all observed line intensities from a wide range of ionization levels and with high accuracy. Our approach is based on the weighted combination of multiple single-cloud photoionization models and, contrary to previous works, the novelty of our approach consists in using the weights as free parameters of the fit and constraining them with the observed data. One of the main applications of HOMERUN is the accurate determination of gas-phase metallicities and we show that a critical point is to allow for a variation of the N/O and S/O abundance ratios which can significantly improve the quality of the fit and the accuracy of the results. Moreover, our approach provides a major improvement compared to the single-cloud, constant-pressure models commonly used in the literature. By using high-quality literature spectra of H ii regions where 10 to 20 emission lines (including several auroral lines) are detected with high signal-to-noise ratio, we show that all lines are reproduced by the model with an accuracy better than 10%. In particular, the model is able to simultaneously reproduce [O i]6300, 6363, [O ii]3726, 3729, [O iii]4959, 5007, [S ii]6717, 6731, and [S iii]9069, 9532 emission lines which, to our knowledge, is an unprecedented result. Finally, we show that the gas metallicities estimated with our models for HII regions in the Milky Way are in agreement with the stellar metallicities than the estimates based on the Te-method. Overall, our method provides a new accurate tool to estimate the metallicity and the physical conditions of the ionized gas. It can be applied to many different science cases from HII regions to AGN and wherever there are emission lines from photoionized gas., Comment: A&A in press, new version following referee report

Studying the feedback process of Active Galactic Nuclei (AGN) requires characterising multiple kinematical components, such as rotating gas and stellar disks, outflows, inflows, and jets. To compare the observed properties with theoretical predictions of galaxy evolution and feedback models and to assess the mutual interaction and energy injection rate into the interstellar medium (ISM), one usually relies on simplified kinematic models. These models have several limitations, as they often do not take into account projection effects, beam smearing and the surface brightness distribution of the emitting medium. Here, we present MOKA3D, an innovative approach to model 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 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 the observations by reconstructing the 3D distribution of emitting clouds and providing accurate estimates of the spatially resolved outflow physical properties (e.g. mass rate, kinetic energy). As an example, we demonstrate the capabilities of our method by applying it to three nearby Seyfert-II galaxies observed with MUSE at the VLT and selected from the 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., Comment: 17 pages, 14 figures

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 ($\sim$7 keV) diffuse plasma is still under debate. In this work we measure the Fe XXV line emission using all available XMM-Newton observations of the Galactic centre (GC) and inner disc ($-10^{\circ}$$<\ell<10^{\circ}$, $-2^{\circ}

We present the Widefield ASKAP L-band Legacy All-sky Blind surveY (WALLABY) Pilot Phase I HI kinematic models. This first data release consists of HI observations of three fields in the direction of the Hydra and Norma clusters, and the NGC 4636 galaxy group. In this paper, we describe how we generate and publicly release flat-disk tilted-ring kinematic models for 109/592 unique HI detections in these fields. The modelling method adopted here - which we call the WALLABY Kinematic Analysis Proto-Pipeline (WKAPP) and for which the corresponding scripts are also publicly available - consists of combining results from the homogeneous application of the FAT and 3DBAROLO algorithms to the subset of 209 detections with sufficient resolution and S/N in order to generate optimized model parameters and uncertainties. The 109 models presented here tend to be gas rich detections resolved by at least 3-4 synthesized beams across their major axes, but there is no obvious environmental bias in the modelling. The data release described here is the first step towards the derivation of similar products for thousands of spatially-resolved WALLABY detections via a dedicated kinematic pipeline. Such a large publicly available and homogeneously analyzed dataset will be a powerful legacy product that that will enable a wide range of scientific studies., Comment: Accepted to PASA

Recent studies have demonstrated that the emission from the circumgalactic medium of the Milky Way displays a relatively high degree of patchiness on angular scales of $\sim10^\circ$. Taking advantage of the Spectrum Roentgen Gamma eROSITA Final Equatorial Depth Survey (eFEDS), we aim to constrain any variation in the soft X-ray surface brightness on scales going from sub-degree to a hundred square degrees. We observe modulations of about $60$% on scales of several degrees and decreasing for higher energies. The observed patchiness is stable over a period of two years, therefore excluding that it is induced by Solar wind charge exchange. We also observe no correlation between such excess and the density of galaxies in the Local Universe, suggesting no strong contribution from the hot baryons in the filaments of the Cosmic web. Instead, the soft X-ray emission is anti-correlated with the column density of absorbing material. Indeed, we can reproduce the spectrum of the bright and dark regions by simply varying the column density of the matter absorbing the emission components located beyond the Local Hot Bubble, while no modulation of the intrinsic emission is required. At high Galactic latitudes, the eROSITA all sky map shows patchiness of the soft X-ray diffuse emission similar to the one observed in the eFEDS field, it is therefore likely that the same "absorption-modulation" is present over the entire sky. These results highlight the importance of an accurate treatment of the absorption effects, to determine the patchiness of the circumgalactic medium., Comment: Accepted for publication in Astronomy and Astrophysics

A classical scenario suggests that ULIRGs transform colliding spiral galaxies into a spheroid dominated early-type galaxy. Recent high-resolution simulations have instead shown that, under some circumstances, rotation disks can be preserved during the merging process or rapidly regrown after coalescence. Our goal is to analyze in detail the ionised gas kinematics in a sample of ULIRGs to infer the incidence of gas rotational dynamics in late-stage interacting galaxies and merger remnants. We analysed MUSE data of a sample of 20 nearby (z<0.165) ULIRGs, as part of the "Physics of ULIRGs with MUSE and ALMA" (PUMA) project. We found that 27% individual nuclei are associated with kpc-scale disk-like gas motions. The rest of the sample displays a plethora of gas kinematics, dominated by winds and merger-induced flows, which make the detection of rotation signatures difficult. On the other hand, the incidence of stellar disk-like motions is ~2 times larger than gaseous disks, as the former are probably less affected by winds and streams. The eight galaxies with a gaseous disk present relatively high intrinsic gas velocity dispersion (sigma = 30-85 km/s), rotationally-supported motions (with gas rotation velocity over velocity dispersion vrot/sigma > 1-8), and dynamical masses in the range (2-7)x1e10 Msun. By combining our results with those of local and high-z disk galaxies from the literature, we found a significant correlation between sigma and the offset from the main sequence (MS), after correcting for their evolutionary trends. Our results confirm the presence of kpc-scale rotating disks in interacting galaxies and merger remnants, with an incidence going from 27% (gas) to ~50% (stars). The ULIRGs gas velocity dispersion is up to a factor of ~4 higher than in local normal MS galaxies, similar to high-z starbursts as presented in the literature., Comment: Accepted for publication in Astronomy and Astrophysics

We present the most sensitive and detailed view of the neutral hydrogen (HI) emission associated with the Small Magellanic Cloud (SMC), through the combination of data from the Australian Square Kilometre Array Pathfinder (ASKAP) and Parkes (Murriyang), as part of the Galactic Australian Square Kilometre Array Pathfinder (GASKAP) pilot survey. These GASKAP-HI pilot observations, for the first time, reveal HI in the SMC on similar physical scales as other important tracers of the interstellar medium, such as molecular gas and dust. The resultant image cube possesses an rms noise level of 1.1 K (1.6 mJy/beam) per 0.98 km s$^{-1}$ spectral channel with an angular resolution of 30$''$ ($\sim$10 pc). We discuss the calibration scheme and the custom imaging pipeline that utilizes a joint deconvolution approach, efficiently distributed across a computing cluster, to accurately recover the emission extending across the entire $\sim$25 deg$^2$ field-of-view. We provide an overview of the data products and characterize several aspects including the noise properties as a function of angular resolution and the represented spatial scales by deriving the global transfer function over the full spectral range. A preliminary spatial power spectrum analysis on individual spectral channels reveals that the power-law nature of the density distribution extends down to scales of 10 pc. We highlight the scientific potential of these data by comparing the properties of an outflowing high velocity cloud with previous ASKAP+Parkes HI test observations., Comment: Accepted for publication in PASA, 34 pages, 18 figures, 5 tables

We present a study of the gas cycle and star formation history in the central 500 pc of the Milky Way, known as Central Molecular Zone (CMZ). Through hydrodynamical simulations of the inner 4.5 kpc of our Galaxy, we follow the gas cycle in a completely self-consistent way, starting from gas radial inflow due to the Galactic bar, the channelling of this gas into a dense, star-forming ring/stream at ~ 200 - 300 pc from the Galactic centre, and the launching of galactic outflows powered by stellar feedback. We find that star formation activity in the CMZ goes through oscillatory burst/quench cycles, with a period of tens to hundreds of Myr, characterised by roughly constant gas mass but order-of-magnitude level variations in the star formation rate. Comparison with the observed present-day star formation rate of the CMZ suggests that we are currently near a minimum of this cycle. Stellar feedback drives a mainly two-phase wind off the Galactic disc. The warm phase dominates the mass flux, and carries 100 - 200 % of the gas mass converted into stars. However, most of this gas goes into a fountain and falls back onto the disc rather than escaping the Galaxy. The hot phase carries most of the energy, with a time-averaged energy outflow rate of 10 - 20 % of the supernova energy budget., Comment: 20 pages, 15 figures, accepted for publication in MNRAS

We investigate the relation between stellar mass and specific stellar angular momentum, or `Fall relation', for a sample of 17 isolated, regularly rotating disc galaxies at z=1. All galaxies have a) rotation curves determined from Halpha emission-line data; b) HST imaging in optical and infrared filters; c) 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 the specific angular momentum by assuming that rotation curves beyond the outermost Halpha 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

We use new high-resolution HI data from the Australian Square Kilometre Array Pathfinder (ASKAP) to investigate the dynamics of the Small Magellanic Cloud (SMC). We model the HI 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 ~ 4 kpc. After correcting for asymmetric drift, the circular velocity slowly rises to a maximum value of Vc ~ 55 km/s at R ~ 2.8 kpc and possibly flattens outwards. In spite of the SMC undergoing strong gravitational interactions with its neighbours, its HI 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 three-dimensional 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(R<4 kpc) = 1-1.5 x 10^9 solar masses is always required to successfully reproduce the observed rotation curve, implying a large baryon fraction of 30%-40%. We discuss the impact of our assumptions and the limitations of deriving the SMC kinematics and dynamics from HI observations., Comment: Accepted for publication in MNRAS

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 SN Refsdal. Sp1149 lies at $z\simeq1.49$, has a stellar mass $M_*\simeq5\times10^9 \, \mathrm{M_\odot}$, a star-formation rate $\mathrm{SFR} \simeq1-6 \, \mathrm{M_\odot/yr}$ and represents a likely progenitor of a Milky-Way-like galaxy. All the four multiple images of Sp1149 in our data show strong OII-line emissions pointing to a clear rotation pattern. We take advantage of the gravitational lensing magnification effect ($\simeq 4 \times$) on the OII emission of the least distorted image to fit 3D 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 $R\simeq1$ kpc and then (initially) declines and flattens to an average $V_\mathrm{flat} = 128^{+29}_{-19}$ km/s. The shape of the rotation curve is well determined but the actual value of $V_\mathrm{flat}$ 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 $27\pm5$ km/s. This value is consistent with $z=0$ measurements in the ionized gas component and a factor 2-4 lower than other estimates in different galaxies at similar redshifts. The average stellar-to-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 ($V / \sigma\simeq5$) spiral galaxy in a 4 Gyr old Universe., Comment: 10 pages, 5 figures. Accepted for publication in MNRAS

The study of the evolution of star-forming galaxies requires the determination of accurate kinematics and scaling relations out to high redshift. In this paper we select a sample of 18 galaxies at z~1, observed in the H-alpha emission-line with KMOS, to derive accurate kinematics using a novel 3D analysis technique. We use the new code 3D-Barolo, that models the galaxy emission directly in the 3D observational space, without the need to extract kinematic maps. This technique's major advantage is that it is not affected by beam smearing and thus it enables the determination of rotation velocity and intrinsic velocity dispersion, even at low spatial resolution. We find that: 1) the rotation curves of these z~1 galaxies rise very steeply within few kiloparsecs and remain flat out to the outermost radius and 2) the H-alpha velocity dispersions are low, ranging from 15 to 40 km/s, which leads to V/sigma = 3-10. These characteristics are similar to those of disc galaxies in the local Universe. Finally, we also report no significant evolution of the stellar-mass Tully-Fisher relation. Our results show that disc galaxies are kinematically mature and rotation-dominated already at z~1., Comment: Accepted for publication in A&A, 11 pages, 6 figures, 1 table

Supernova (SN) Refsdal is the first multiply-imaged, highly-magnified, and spatially-resolved SN ever observed. The SN exploded in a highly-magnified spiral galaxy at z=1.49 behind the Frontier Fields Cluster MACS1149, and provides a unique opportunity to study the environment of SNe at high z. We exploit the time delay between multiple images to determine the properties of the SN and its environment, before, during, and after the SN exploded. We use the integral-field spectrograph MUSE on the VLT to simultaneously target all observed and model-predicted positions of SN Refsdal. We find MgII emission at all positions of SN Refsdal, accompanied by weak FeII* emission at two positions. The measured ratios of [OII] to MgII emission of 10-20 indicate a high degree of ionization with low metallicity. Because the same high degree of ionization is found in all images, and our spatial resolution is too coarse to resolve the region of influence of SN Refsdal, we conclude that this high degree of ionization has been produced by previous SNe or a young and hot stellar population. We find no variability of the [OII] line over a period of 57 days. This suggests that there is no variation in the [OII] luminosity of the SN over this period, or that the SN has a small contribution to the integrated [OII] emission over the scale resolved by our observations., Comment: 5 pages, 4 figures, accepted for publication in A&A