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This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., Mrk 477 is the closest type-2 quasar, at a distance of 163 Mpc. This makes it an ideal laboratory for studying the interplay between nuclear activity and star formation with a great level of detail and signal-to-noise. In this Letter we present new mid-infrared (mid-IR) imaging and spectroscopic data with an angular resolution of 0.4″ (∼300 pc) obtained with the Gran Telescopio Canarias instrument CanariCam. The N-band (8–13 μm) spectrum of the central ∼400 pc of the galaxy reveals [S IV]λ10.51 μm emission, but no 8.6 or 11.3 μm polycyclic aromatic hydrocarbon (PAH) features, which are commonly used as tracers of recent star formation. This is in stark contrast with the presence of a nuclear starburst of ∼300 pc in size, an age of 6 Myr, and a mass of 1.1×108 M⊙, as constrained from ultraviolet Hubble Space Telescope observations. Considering this, we argue that even the more resilient, neutral molecules that mainly produce the 11.3 μm PAH band are most likely being destroyed in the vicinity of the active nucleus despite the relatively large X-ray column density, log NH = 23.5 cm−2, and modest X-ray luminosity, 1.5×1043 erg s−1. This highlights the importance of being cautious when using PAH features as star formation tracers in the central region of galaxies to evaluate the impact of feedback from active galactic nuclei. © The Authors 2023., Based on observations made with the GTC, installed at the Spanish Observatorio del Roque de los Muchachos of the IAC, on the island of La Palma. CASSIS is a product of the IRS instrument team, supported by NASA and JPL, by the “Programme National de Physique Stellaire” (PNPS) of CNRS/INSU co-funded by CEA and CNES and through the “Programme National Physique et Chimie du Milieu Interstellaire” (PCMI) of CNRS/INSU with INC/INP co-funded by CEA and CNES. CRA acknowledges the hospitality of the Kavli Institute for Cosmology of the University of Cambridge, where this manuscript was written, in August 2022. This stay was funded by the Spanish MICINN through the Spanish State Research Agency, under Severo Ochoa Centres of Excellence Programme 2020-2023 (CEX2019-000920-S). CRA and PSB acknowledge support from the projects “Quantifying the impact of quasar feedback on galaxy evolution”, with reference EUR2020-112266, funded by MICINN-AEI/10.13039/501100011033 and the European Union NextGenerationEU/PRTR, and from the Consejería de Economía, Conocimiento y Empleo del Gobierno de Canarias and the European Regional Development Fund (ERDF) under grant “Quasar feedback and molecular gas reservoirs”, with reference ProID2020010105, ACCISI/FEDER, UE. AAH acknowledges financial support from grant PID2021-124665NB-I00 funded by the Spanish Ministry of Science and Innovation. SC acknowledges financial support from the State Agency for Research of the Spanish MCIU through the “Center of Excellence Severo Ochoa” award to the IAA (SEV-2017-0709). We finally thank the referee for his constructive report, and the GTC staff for their constant support., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).

The far-IR/sub-mm wavelength range contains a wealth of diagnostic information that is important for understanding the role of radio AGN in galaxy evolution. Here we present the results of Herschel PACS and SPIRE observations of a complete sample of 46 powerful 2Jy radio AGN at intermediate redshifts (0.05 < z < 0.7), which represent the deepest pointed observations of a major sample of radio AGN undertaken by Herschel. In order to assess the importance of non-thermal synchrotron emission at far-IR wavelengths, we also present new APEX sub-mm and ALMA mm data. We find that the overall incidence of non-thermal contamination in the PACS bands ($ $200$μ$m) sampled by the SPIRE instrument. Non-thermal contamination is strongest in objects with compact CSS/GPS or extended FRI radio morphologies, and in those with type 1 optical spectra. Considering thermal dust emission, we find strong correlations between the 100 and 160$μ$m monochromatic luminosities and AGN power indicators, providing further evidence that radiation from the AGN may be an important heating source for the far-IR emitting dust. Clearly, AGN contamination -- whether by the direct emission from synchrotron-emitting lobes and cores, or via radiative heating of the cool dust -- needs to be carefully considered when using the far-IR continuum to measure the star formation rates in the host galaxies of radio AGN., 22 pages, 8 figures, Accepted in MNRAS

We present CO(2-1) and adjacent continuum observations of 7 nearby radio-quiet type-2 quasars (QSO2s) obtained with ALMA at ~0.2" resolution (370 pc at z~0.1). The CO morphologies are diverse, including disks and interacting systems. Two of the QSO2s are red early-type galaxies with no CO(2-1) detected. In the interacting galaxies, the central kpc contains 18-25% of the total cold molecular gas, whereas in the spirals it is only 5-12%. J1010+0612 and J1430+1339 show double-peaked CO morphologies which do not have optical counterparts. Based on our analysis of the ionized and molecular kinematics and mm continuum emission, these CO morphologies are most likely produced by AGN feedback in the form of outflows, jets, and/or shocks. The CO kinematics of the QSO2s are dominated by rotation but also reveal noncircular motions. According to our analysis of the kinematics, these noncircular motions correspond to molecular outflows mostly coplanar with the CO discs in four of the QSO2s, and either to a coplanar inflow or vertical outflow in the case of J1010+0612. These outflows represent 0.2-0.7% of the QSO2s' total molecular gas mass and have maximum velocities of 200-350 km/s, radii from 0.4 to 1.3 kpc, and outflow rates of 8-16 Msun/yr. These properties are intermediate between those of the mild molecular outflows measured for Seyferts, and the fast and energetic outflows of ULIRGs. This suggests that it is not only AGN luminosity that drives massive molecular outflows. Other factors such as jet power, coupling between winds, jets, and/or ionized outflows and the CO discs, and amount or geometry of dense gas in the nuclear regions might be also relevant. Thus, although we do not find evidence for a significant impact of quasar feedback on the total molecular gas reservoirs and SFRs, it appears to be modifying the distribution of cold molecular gas in the central kpc of the galaxies., Comment: 29 pages including 18 figures, 7 tables and appendices. A&A accepted version including minor edits

We present the detection of enormous disks/rings of neutral hydrogen (HI) gas around several nearby radio‐loud early‐type galaxies. Goal of our study was to use HI observations to look for evidence of galaxy mergers or interactions (tails, bridges, disks, etc.) that could be related to the triggering of the radio source in a complete sample of nearby radio galaxies. One case, B2 0648+27, was studied in great detail to be a product of a major merger—it is a direct link between (Ultra‐) Luminous Infra‐Red Galaxies and Radio Galaxies, for which we trace the different stages of merger, starburst and AGN activity. We detect other large‐scale HI disks and rings only around the host galaxies of several low‐power compact radio sources as well as the powerful FR‐II radio galaxy NGC 612; the hosts of extended FR‐I radio sources seem to be devoid of large‐scale HI. This suggest a fundamental difference in the host galaxy properties—and perhaps also the triggering mechanism—of different types of radio sources.

An optical study of CSS radio sources is presented.

Summary We present new long-slit and narrow-band imaging observations of the nebula surrounding the peculiar variable star V348 Sgr. These show that the overall ionization state of the nebula is low, but the extent, structure and physical conditions are all typical of old planetary nebulae. An analysis of the abundances shows a pronounced helium enrichment, indicating that the system is highly evolved. Further clues to the past evolution of the system are provided by models which demonstrate that the ionization structure of the nebula is incompatible with ionization by a central star of temperature 20000 K and luminosity 3500 L⊙ as suspected for V348 Sgr. As there are no indications of a hotter star in the system, we are forced to accept that the star must have been hotter in the very recent past (nebular recombination time-scale is 120 < τrec < 2300 yr). Given all the observational facts, the evolutionary status of V348 Sgr is interpreted as a white dwarf that has suffered a last thermal pulse, reigniting a helium-burning shell. The lower limit for τrec is probably just consistent with the post-pulse crossing time required to reach the AGB, while the upper limit suggests the star may have already reached the AGB and is currently evolving to higher temperatures again. The present data do not allow us to differentiate between these two scenarios.

We use deep Herschel observations of the complete 2Jy sample of powerful radio AGNs in the local universe (0.05 < z < 0.7) to probe their cool interstellar medium (ISM) contents and star-forming properties, comparing them against other samples of nearby luminous AGNs and quiescent galaxies. This allows us to investigate triggering and feedback mechanisms. We find that the dust masses of the strong-line radio galaxies (SLRGs) in our sample are similar to those of radio-quiet quasars, and that their median dust mass (Mdust = 2 x 10^7 Msun) is enhanced by a factor ~200 compared to that of non-AGN ellipticals, but lower by a factor ~16 relative to that of local ultra-luminous infrared galaxies (UILRGs). Along with compelling evidence for merger signatures in optical images, the SLRGs in our sample also show relatively high star-formation efficiencies, despite the fact that many of them fall below the main sequence for star forming galaxies. Together, these results suggest that most of our SLRGs have been re-triggered by late-time mergers that are relatively minor in terms of their gas contents. In comparison with the SLRGs, the radio AGNs with weak optical emission lines (WLRGs) and edge-darkened radio jets (FRIs) have both lower cool ISM masses and star-formation rates (by a factor of >30), consistent with being fuelled by a different mechanism (e.g. the direct accretion of hot gas)., 20 pages, 8 figures, accepted for publication in MNRAS