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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], [O ii], [O iii], [S ii], and [S iii] 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: Submitted to A&A, comments welcome

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 novel Gaia Multi Peak (GMP) technique has proven to be able to successfully select dual and lensed AGN candidates at sub-arcsec separations. Both populations are important because dual AGNs represent one of the central, still largely untested, predictions of lamdaCDM cosmology, and compact lensed quasars allow to probe the central regions of the lensing galaxies. In this work, we present high spatial resolution spectroscopy of twelve GMP-selected systems. We use the the adaptive-optics assisted integral-field spectrograph MUSE at VLT to resolve each system and study the nature of each component. All the targets reveal the presence of two components confirming the GMP selection. We classify five targets as dual AGNs, two as lensed systems, and five as a chance alignment of a star and and AGN. Having separations between 0.30" and 0.86", these dual and lensed systems are, to date, among the most compact ever discovered at z >0.3. This is the largest sample of distant dual AGNs with sub-arcsec separations ever presented in a single paper., Comment: 12 pages, 10 figures

The Gaia-Multi-Peak (GMP) technique can be used to identify large numbers of dual or lensed AGN candidates at sub-arcsec separation, allowing us to study both multiple SMBHs in the same galaxy and rare, compact lensed systems. The observed samples can be used to test the predictions of the models of SMBH merging once 1) the selection function of the GMP technique is known, and 2) each system has been classified as dual AGN, lensed AGN, or AGN/star alignment. Here we show that the GMP selection is very efficient for separations above 0.15'' when the secondary (fainter) object has magnitude G<20.5. We present the spectroscopic classification of five GMP candidates using VLT/ERIS and Keck/OSIRIS, and compare them with the classifications obtained from: a) the near-IR colors of 7 systems obtained with LBT/LUCI, and b) the analysis of the total, spatially-unresolved spectra. We conclude that colors and integrated spectra can already provide reliable classifications of many systems. Finally, we summarize the confirmed dual AGNs at z>0.5 selected by the GMP technique, and compare this sample with other such systems from the literature, concluding that GMP can provide a large number of confirmed dual AGNs at separations below 7 kpc., Comment: 14 pages,A&A, in press

Amongst the more than 18 different forms of water ice, only the common hexagonal phase and the cubic phase are present in nature on Earth. Nonetheless, it is now widely recognized that all samples of ‘cubic ice’ discovered so far do not have a fully cubic crystal structure but instead are stacking-disordered forms of ice I (namely, ice Isd), which contain both hexagonal and cubic stacking sequences of hydrogen-bonded water molecules. Here, we describe a method to obtain large quantities of cubic ice Ic with high structural purity. Cubic ice Ic is formed by heating a powder of D2O ice XVII obtained from annealing of pristine C0 hydrate samples under dynamic vacuum. Neutron diffraction experiments performed on two different instruments and Raman spectroscopy measurements confirm the structural purity of the cubic ice, Ic. These findings contribute to a better understanding of ice I polymorphism and the existence of the two natural ice forms.

Deuterated ice XVII, a metastable solid water polymorph, was filled with Ne and O2 at p ≈ 100 kPa and studied by in situ neutron diffraction (ILL, France). Powder patterns were collected in the ranges of 20-50 K (Ne) and 4.6-90 K (O2). Rietveld refinement and difference Fourier techniques showed that the gas molecules were located inside the hexagonal channels of the host ice. Both Ne atoms and O2 molecules are arranged in a spiral-like configuration off the channel axis, preserving the P6122 symmetry of the host in the case of Ne, but reducing it to P61 in O2. A larger Ne absorption compared to Ne-filled ice II is observed, which is consistent with longer host-guest contacts producing smaller hydrophobic repulsion. In O2-filled ice XVII, instead, short O-D distances (2.37 Å) have attractive character and stabilize the structure.

This book develops and updates the systemic approach in existing disciplines including physics, biology, ecology and systemics, but also introduces it in humanistic disciplines like philosophy, architecture, economy, legal studies, and classical studies. Contributes to the consolidation and expansion of systemic thinking as a necessary integration of the general reductionist and dominant analytical attitude. Supports the diffusion of new concepts and research methods in systemic thinking. This book is dedicated to the consolidation and to the expansion of theoretic systems thinking

Per risolvere il problema del rapporto mente-cervello/corpo occorre rivedere un sostanzioso gruppo di concetti di riferimento e correggerli, tra cui:materialismo, scientismo, fisicalismo, riduzionismo, meccanicismo. Sarà così possibile spostare l'attenzione all'essere umano nella sua unità sostanziale e darle una veste teorica aggiornata in termini di pensiero sistemico. Alla luce di queste revisioni e proposte la mente può essere considerata una proprietà di II livello del sistema essere umano e il corpo la manifestazione fenomenica completa, non solo biologica, dell'umano

Per risolvere il problema del rapporto mente-cervello/corpo occorre rivedere un sostanzioso gruppo di concetti di riferimento e correggerli, tra cui:materialismo, scientismo, fisicalismo, riduzionismo, meccanicismo. Sarà così possibile spostare l'attenzione all'essere umano nella sua unità sostanziale e darle una veste teorica aggiornata in termini di pensiero sistemico. Alla luce di queste revisioni e proposte la mente può essere considerata una proprietà di II livello del sistema essere umano e il corpo la manifestazione fenomenica completa, non solo biologica, dell'umano

Questo contributo ricostruisce il passaggio da una concezione “forte” della conoscenza al modello “debole”, assai più variegato, che ha messo in luce i limiti della precedente impostazione. Il modello “forte”, sostenuto in età con-temporanea dal neopositivismo, vanta una lunga tradizione a partire dall’età moderna, in quanto intende la conoscenza come episteme. Da Popper in poi l’epistemologia ha preso atto che il modello fondazionalista è insostenibile, ma non ha saputo costruire un modello alternativo, che evitasse tanto il relativismo quanto lo scetticismo. Questo saggio suggerisce una direzione in cui l’epistemologia può muoversi al fine di ripensare e, in qualche caso dissolvere, i principali problemi sollevati dalla crisi del modello “forte”, adottanto una prospettiva sistemica, secondo cui la conoscenza non è un mero aggregato di elementi, ma è tale grazie alle relazioni e alle interazioni che si realizzano fra soggetto e oggetto e fra i diversi soggetti conoscenti.

Questo contributo ricostruisce il passaggio da una concezione “forte” della conoscenza al modello “debole”, assai più variegato, che ha messo in luce i limiti della precedente impostazione. Il modello “forte”, sostenuto in età con-temporanea dal neopositivismo, vanta una lunga tradizione a partire dall’età moderna, in quanto intende la conoscenza come episteme. Da Popper in poi l’epistemologia ha preso atto che il modello fondazionalista è insostenibile, ma non ha saputo costruire un modello alternativo, che evitasse tanto il relativismo quanto lo scetticismo. Questo saggio suggerisce una direzione in cui l’epistemologia può muoversi al fine di ripensare e, in qualche caso dissolvere, i principali problemi sollevati dalla crisi del modello “forte”, adottanto una prospettiva sistemica, secondo cui la conoscenza non è un mero aggregato di elementi, ma è tale grazie alle relazioni e alle interazioni che si realizzano fra soggetto e oggetto e fra i diversi soggetti conoscenti.