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The pace at which galaxies grew into their current stellar masses and how this growth is regulated is still not fully understood, nor is the role that morphology plays in this process. We applied full spectral fitting techniques with pyPipe3D to the MaNGA sample to obtain its star formation and stellar mass histories and used these to investigate the mass assembly of galaxies by measuring how their specific star formation correlates to their stellar mass at different look-back times. We find that the correlation between these two parameters was shallower in the past. Galaxies used to have similar mass doubling times and the current negative correlation between the specific star formation and M* is primarily due to more massive galaxies 'dropping' off the main sequence earlier than less massive ones. Additionally, selecting the galaxies into bins based on their present-day morphology shows a segregation in specific star formation rate (sSFR) that is maintained even at high look-back times, showing that the factors that determine which morphology a galaxy ends up in are in place at very early times. Similarly, selecting them based on their current star formation status shows that, on average, currently retired galaxies used to have slightly a higher sSFR before the drop-off, whereas galaxies that have continued to form stars until today had a lower sSFR initially. We compare our results to a set of cosmic surveys, finding partial agreement in our results with several of them, though with significant offsets in redshift. Finally, we discuss how our results fit with certain theoretical models on galaxy evolution as well as cosmological simulations. [ABSTRACT FROM AUTHOR]

Context. In stars, metallicity is usually traced using Fe, while in nebulae, O serves as the preferred proxy. Both elements have different nucleosynthetic origins and are not directly comparable. Additionally, in ionized nebulae, Fe is heavily depleted onto dust grains. Aims. We investigate the distribution of Fe gas abundances in a sample of 452 star-forming nebulae with [Fe III] λ4658 detections and their relationship with O and N abundances. Additionally, we analyze the depletion of Fe onto dust grains in photoionized environments. Methods. We homogeneously determined the chemical abundances with direct determinations of electron temperature (Te), considering the effect of possible internal variations of this parameter. We adopted a sample of 300 Galactic stars to interpret the nebular findings. Results. We find a moderate linear correlation (r = −0.59) between Fe/O and O/H. In turn, we report a stronger correlation (r = −0.80) between Fe/N and N/H. We interpret the tighter correlation as evidence that Fe and N are produced on similar timescales while Fe- dust depletion scales with the Fe availability. The apparently flat distribution between Fe/N and N/H in Milky Way stars supports this interpretation. We find that when 12+log(O/H)<7.6, the nebulae seem to reach a plateau value around log(Fe/O) ≈ −1.7. If this trend were confirmed, it would be consistent with a very small amount of Fe dust in these systems, similar to what is observed in high-z galaxies discovered by the James Webb Space Telescope (JWST). We derive a relationship that allows us to approximate the fraction of Fe trapped into dust in ionized nebulae. If the O-dust scales in the same way, its possible contribution in low-metallicity nebulae would be negligible. After analyzing the Fe/O abundances in J0811+4730 and J1631+4426, we do not see evidence of the presence of very massive stars with Minit > 300 M⊙ in these systems. Conclusions. The close relation observed between the N and Fe abundances has the potential to serve as a link between stellar and nebular chemical studies. This requires an expansion of the number of abundance determinations for these elements in both stars and star-forming nebulae, especially at low metallicities. [ABSTRACT FROM AUTHOR]

In this study, we explore the impact of the galactic interaction/mergers on the central oxygen abundance. We analyse 234 star-forming galaxies included in the Calar Alto Legacy Integral Field Area survey with integrated molecular gas observations from the Atacama Pathfinder EXperiment millimeter telescope and the CARMA interferometer. This database has the most optical integral field spectroscopy data with CO data for yet, with integrated measurements within |$\sim 1~{R_{\rm{eff}}}$|⁠. Our sample includes 125 isolated galaxies (control sample) and 109 galaxies in different merging stages. We find that despite whether the merging galaxies show an increase or decrease in their molecular gas fraction, the oxygen abundance does not vary significantly, in comparison to our control sample. Therefore, the enhancement and suppression of oxygen abundance are similar in both isolated galaxies and interacting/merging galaxies. On the contrary, regardless of the merger stage (including isolated sample), galaxies that present an increase in their specific star formation rate present a metallicity dilution. We suggest that both internal and external events affect the chemical composition of merging galaxies. [ABSTRACT FROM AUTHOR]

We present the Bidimensional Exploration of the warm-Temperature Ionised gaS (BETIS) project, designed for the spatial and spectral study of the diffuse ionised gas (DIG) in a selection of nearby spiral galaxies observed with the MUSE integral-field spectrograph. Our primary objective is to investigate the various ionisation mechanisms at play within the DIG. We analysed the distribution of high- and low-ionisation species in the optical spectra of the sample on a spatially resolved basis. We introduced a new methodology for spectroscopically defining the DIG, optimised for galaxies of different resolutions. Firstly, we employed an innovative adaptive binning technique on the observed datacube based on the spectroscopic signal-to-noise ratio (S/N) of the collisional [S II] line to increase the S/N of the rest of the lines including [O III], [O I], and He I. Subsequently, we created a DIG mask by eliminating the emissions associated with both bright and faint H II regions. We also examined the suitability of using Hα equivalent width (EWHα) as a proxy for defining the DIG and its associated ionisation regime. Notably, for EWHα < 3 Å – the expected emission from hot low-mass evolved stars (HOLMES) – the measured value is contingent on the chosen population synthesis technique performed. Our analysis of the showcase sample reveals a consistent cumulative DIG fraction across all galaxies in the sample, averaging around 40%–70%. The average radial distribution of the [N II]/Hα, [S II]/Hα, [O I]/Hα, and [O III]/Hβ ratios are enhanced in the DIG regimes (up to 0.2 dex). It follows similar trends between the DIG regime and the H II regions, as well as the Hα surface brightness (ΣHα), indicating a correlation between the ionisation of these species in both the DIG and the H II regions. The DIG loci in typical diagnostic diagrams are found, in general, within the line ratios that correspond to photoionisation due to the star formation. There is a noticeable offset correspondent to ionisation due to fast shocks. However, an individual diagnosis performed for each galaxy reveals that all the DIG in these galaxies can be attributed to photoionisation from star formation. The offset is primarily due to the contribution of Seyfert galaxies in our sample, which is closely aligned with models of ionisation from fast shocks and galactic outflows, thus mimicking the DIG emission. Our results indicate that galaxies exhibiting active galactic nucleus (AGN) activity should be considered separately when conducting a general analysis of the DIG ionisation mechanisms, since this emission is indistinguishable from high-excitation DIG. [ABSTRACT FROM AUTHOR]

We present a catalogue of ∼52 000 extragalactic H  ii regions and their spectroscopic properties obtained using Integral Field Spectroscopy (IFS) from MUSE observations. The sample analysed in this study contains 678 galaxies within the nearby Universe (0.004 < z < 0.06) covering different morphological types and a wide range of stellar masses (6 < log(M */M⊙) < 13). Each galaxy was analysed using the pipe3d and pyhiiextractor codes to obtain information of the ionized gas and underlying stellar populations. Specifically, the fluxes, equivalent widths, velocities and velocity dispersions of 30 emission lines covering the wavelength range between λ4750 to λ9300 Å, were extracted and were used to estimate luminosity weighted ages and metallicities of the underlying stellar populations from each H  ii region (of the original sample we detect H  ii regions in 539 galaxies). In addition, we introduce and apply a novel method and independent of any intrinsic physical property to estimate and decontaminate the contribution of the diffuse ionized gas. Using the final catalogue, we explore the dependence of properties of the H  ii regions on different local and global galaxy parameters: (i) Hubble type, (ii) stellar mass, (iii) galactocentric distance, and (iv) the age and metallicity of the underlying/neighbour stellar populations. We confirm known relations between properties of the H  ii regions and the underlying stellar populations (in particular, with the age) uncovered using data of lower spatial and spectral resolution. Furthermore, we describe the existence of two main families of diffuse ionized gas different for galaxies host or not of H  ii regions. [ABSTRACT FROM AUTHOR]

Context. The usual approach to classify the ionizing source using optical spectroscopy is based on the use of diagnostic diagrams that compare the relative strength of pairs of collisitional metallic lines (e.g., [O III] and [N II]) to recombination hydrogen lines (e.g., Hβ and Hα). Despite it having been accepted as the standard procedure, it presents known problems, including confusion regimes and/or limitations related to the required signal-to-noise (S/N) of the emission lines involved. These problems not only affect our intrinsic understanding of the interstellar medium and its properties, but also the fundamental galaxy properties, such as the star formation rate and the oxygen abundance. This raises key questions related to the fraction of active galactic nuclei and other essential parameters. Aims. We attempt to minimize the problems introduced by the use of these diagrams, in particular, their implementation when the available information is limited due to either the fact that not all lines are available or they do not have the required S/N value. Methods. We explored the existing alternatives in the literature to minimize the confusion among different ionizing sources. We have proposed a new, simple diagram that uses the equivalent width and the velocity dispersion from one single emission line, Hα, to classify the ionizing sources. Results. We used aperture-limited and spatially resolved spectroscopic data from the nearby Universe (z ∼ 0.01) to demonstrate that the new diagram, which we have named WHaD, segregates the different ionizing sources in a more efficient way than earlier procedures. A new set of regions have been defined in this diagram to select among different ionizing sources. Conclusions. The new proposed diagram is well positioned to assist in determining the ionizing source when only Hα is available or when the S/N of the emission lines is too low to obtain reliable fluxes for the weakest emission lines in classical diagnostic diagrams (e.g., Hβ). [ABSTRACT FROM AUTHOR]

This paper describes the extended data release (eDR) of the Calar Alto Legacy Integral Field Area (CALIFA) survey. It comprises science-grade quality data for 895 galaxies obtained with the Potsdam Multi Aperture Spectograph/PPak instrument at the 3.5-m telescope at the Calar Alto Observatory along the last 12 yr, using the V500 setup [3700–7500 Å, 6 Å/full-width at half-maximum (FWHM)] and the CALIFA observing strategy. It includes galaxies of any morphological type, star formation stage, a wide range of stellar masses (∼107–1012 M⊙), at an average redshift of ∼0.015 (90 per cent within 0.005 < z < 0.05). Primarily selected based on the projected size and apparent magnitude, we demonstrate that it can be volume corrected resulting in a statistically limited but representative sample of the population of galaxies in the nearby Universe. All the data were homogeneous re-reduced, introducing a set of modifications to the previous reduction. The most relevant is the development and implementation of a new cube-reconstruction algorithm that provides with an (almost) seeing-limited spatial resolution (FWHMPSF ∼ 1.0 arcsec). To illustrate the usability and quality of the data, we extracted two aperture spectra for each galaxy (central 1.5 arcsec and fully integrated), and analyse them using pyFIT3D. We obtain a set of observational and physical properties of both the stellar populations and the ionized gas, that have been compared for the two apertures, exploring their distributions as a function of the stellar masses and morphologies of the galaxies, comparing with recent results in the literature. [ABSTRACT FROM AUTHOR]

Context. The analysis of core-collapse supernova (CCSN) environments can provide important information on the life cycle of massive stars and constrain the progenitor properties of these powerful explosions. The MUSE instrument at the Very Large Telescope (VLT) enables detailed local environment constraints of the progenitors of large samples of CCSNe. Using a homogeneous SN sample from the All-Sky Automated Survey for Supernovae (ASAS-SN) survey, an untargeted and spectroscopically complete transient survey, has enabled us to perform a minimally biased statistical analysis of CCSN environments. Aims. We analyze 111 galaxies observed by MUSE that hosted 112 CCSNe – 78 II, nine IIn, seven IIb, four Ic, seven Ib, three Ibn, two Ic-BL, one ambiguous Ibc, and one superluminous SN – detected or discovered by the ASAS-SN survey between 2014 and 2018. The majority of the galaxies were observed by the All-weather MUse Supernova Integral field Nearby Galaxies (AMUSING) survey. Here we analyze the immediate environment around the SN locations and compare the properties between the different CCSN types and their light curves. Methods. We used stellar population synthesis and spectral fitting techniques to derive physical parameters for all H II regions detected within each galaxy, including the star formation rate (SFR), Hα equivalent width (EW), oxygen abundance, and extinction. Results. We found that stripped-envelope supernovae (SESNe) occur in environments with a higher median SFR, Hα EW, and oxygen abundances than SNe II and SNe IIn/Ibn. Most of the distributions have no statistically significant differences, except between oxygen abundance distributions of SESNe and SNe II, and between Hα EW distributions of SESNe and SNe II. The distributions of SNe II and IIn are very similar, indicating that these events explode in similar environments. For the SESNe, SNe Ic have higher median SFRs, Hα EWs, and oxygen abundances than SNe Ib. SNe IIb have environments with similar SFRs and Hα EWs to SNe Ib, and similar oxygen abundances to SNe Ic. We also show that the postmaximum decline rate, s, of SNe II correlates with the Hα EW, and that the luminosity and the Δm15 parameter of SESNe correlate with the oxygen abundance, Hα EW, and SFR at their environments. This suggests a connection between the explosion mechanisms of these events to their environment properties. [ABSTRACT FROM AUTHOR]

Using spatially resolved fossil record analysis on a large sample of 'red and dead' elliptical galaxies (classical ellipticals, CLEs) from the MaNGA/SDSS-IV DR15 survey, we reconstruct the archaeological evolution of their radial gradients in mass-to-luminosity ratio (M / L), g − r colour, and specific star formation (SF) rate. We also calculate other metrics that quantify the inside-out SF quenching and external mass growth processes. The M / L gradients, ∇Υ⋆, are approximately flat at high look-back times (t lb), but then they become negative and steeper until an epoch, when this trend reverses. These trends are shifted to later epochs the less massive the galaxies are. Colour gradients follow qualitatively similar trends. We find that these trends are mainly driven by strong inside-out quenching, without significant outer growth or structural changes overall. Our results suggest a scenario where the main progenitors of local CLE galaxies evolved quasi-passively after an early dissipative phase, but underwent radial photometric changes due to the inside-out quenching that led to the systematic decrease of ∇Υ⋆ and to an increase of the light-weighted radius. The late reversing of ∇Υ⋆, t lb≈2 − 4 Gyr, roughly coincides with the global quenching of the CLE galaxies. We have pushed archaeological inferences to the limit, but thanks to the large number of objects and an understanding of how the caveats and assumptions affect our results, we conclude that they offer an average description of evolutionary behaviours of CLE progenitors that is valid at least qualitatively. [ABSTRACT FROM AUTHOR]

A complete demographic of active galactic nuclei (AGNs) is essential to understand the evolution of the Universe. Optical surveys estimate the population of AGNs in the local Universe to be of ∼ 4 per cent. However, these results could be biased towards bright sources, not affected by the host galaxy attenuation. An alternative method for detecting these objects is through the X-ray emission. In this work, we aim to complement the AGN population of the optical CALIFA survey (941 sources), by using X-ray data from Chandra , which provides the best spatial resolution to date, essential to isolate the nuclear emission from the host galaxy. We study a total of 138 sources with available data. We find 34 new bona fide AGNs and 23 AGN candidates, which could increase the AGN population to 7–10  per cent among the CALIFA survey. X-rays are particularly useful for low-luminosity AGNs since they are excluded by the criterion of large equivalent width of the |$\rm {H\alpha }$| emission line when applied to optical selections. Indeed, placing such a restrictive criteria might cause a loss of up to 70 per cent of AGN sources. X-ray detected sources are preferentially located in the right side of the [ |${\mathrm{O}}\, {\small {\rm III}}$| ]/Hβ versus [ |${\mathrm{N}}\, {\small {\rm II}}$| ]/Hα diagram, suggesting that this diagram might be the most reliable at classifying AGN sources. Our results support the idea that multiwavelength studies are the best way to obtain a complete AGN population. [ABSTRACT FROM AUTHOR]

We present here the exploration of the physical properties of the sample of H  ii regions and aggregations of the last H  ii regions catalogue of the Calar Alto Legacy Integral Field Area (CALIFA) survey. This sample comprises the optical spectroscopic properties of more than ∼26 000 ionized regions corresponding to 924 galaxies from the Integral Field Spectroscopy data, including the flux intensity and equivalent widths and the properties of their underlying stellar population. In the current study, we derive a set of physical quantities for all these regions based on those properties, including (i) the fraction of young stars; (ii) the ionization strength (using six different estimations); (iii) the oxygen abundance (using 25 different calibrators); (iv) the nitrogen and nitrogen-to-oxygen abundance; (v) the dust extinction; and (vi) the electron density. Using this data set, we explore how the loci in the classical diagnostic diagrams are connected with those quantities, the radial distributions of these parameters, and the interrelations between themselves and with the properties of the underlying stellar populations. We conclude that many properties of the H  ii regions are tightly related to the galactic stellar evolution at the location where those regions are observed. Those properties are modulated only as a second-order effect by the properties of the ionizing stars and the ionized nebulae that do not depend on the astrophysical context in which they are formed. Our results highlight the importance of H  ii regions to explore the chemical evolution in galaxies, clarifying which of their properties can be used as proxies of that evolution. [ABSTRACT FROM AUTHOR]

We apply stellar population synthesis analysis to obtain spatially resolved archaeological inferences for a large sample of 'red and dead' Elliptical galaxies (Classical Ellipticals, CLEs) from the MaNGA/SDSS-IV DR15 survey. From their 2D stellar light and mass maps, we explore the differences between the radial mass and light distributions in the rest-frame bands g ,  r , and i as functions of look-back time, t lb, or redshift, z. We characterize these differences through the ratios between the following mass- and light-derived global properties: sizes, concentrations, and effective surface densities. We find that the mass-to-light ratios of these properties change with t lb, more the more massive the galaxies are. The CLE galaxy archaeological progenitors are, on average, less compact, concentrated, and dense in light than in mass as z decreases. However, at later times, when also the evolution of the progenitors becomes passive at all radii, there is an upturn in these trends and the differences between mass and light in compactness/concentration decrease towards z ∼ 0. The trends in the ratios of mass-to-light sizes agree qualitatively with results from direct observations in galaxy surveys at different redshifts. We discuss the caveats and interpretations of our results, and speculate that the strong structural evolution found in some previous studies for early-type galaxies could be explained partially by photometric changes rather than by intrinsic structural changes. [ABSTRACT FROM AUTHOR]

According to theory, the torus of active galactic nuclei (AGN) is sustained from a wind coming off the accretion disc, and for low efficient AGN, it has been proposed that such structure disappears. However, the exact conditions for its disappearance remain unclear. This can be studied throughout the reflection component at X-rays, which is associated with distant and neutral material at the inner walls of the torus in obscured AGN. We select a sample of 81 AGNs observed with NuSTAR with a distance limit of D< 200 Mpc and Eddington rate |$\rm {\lambda _{Edd} \equiv L_{bol}/L_{Edd}\lt 10^{-3}}$|⁠. We fit the 3–70 keV spectra using a model accounting for a partial-covering absorber plus a reflection component from neutral material. We find that the existence of the reflection component spans in a wide range of black hole mass and bolometric luminosities, with only ∼13 per cent of our sample (11 sources) lacking of any reflection signatures. These sources fall in the region in which the torus may be lacking in the L-MBH diagram. For the sources with a detected reflection component, we find that the vast majority of them are highly obscured (⁠|$\rm {\log \ N_H \gt 23}$|⁠), with |$\rm {\sim 20{{\ \rm per\ cent}}}$| being Compton-thick. We also find an increase in the number of unobscured sources and a tentative increase on the ratio between |$\rm {FeK\alpha }$| emission line and Compton-hump luminosities toward |$\rm {\lambda _{Edd}=10^{-5}}$|⁠ , suggesting that the contribution of the |$\rm {FeK\alpha }$| line changes with Eddington ratio. [ABSTRACT FROM AUTHOR]

Keywords: errata; addenda; galaxies: general; galaxies: statistics; galaxies: stellar content; galaxies: structure EN errata addenda galaxies: general galaxies: statistics galaxies: stellar content galaxies: structure 2746 2752 7 01/24/22 20220215 NES 220215 This is an erratum to the paper 'Resolving the age bimodality of galaxy stellar populations on kpc scales' (2017, MNRAS, 468, 1902-1916). Errata, addenda, galaxies: general, galaxies: statistics, galaxies: stellar content, galaxies: structure. [Extracted from the article]

Helium is the second most common chemical species in the Universe. The study of helium abundance has the potential to unravel the chemical evolution of and within galaxies. In this study, we provide an empirical calibration for the singly ionized helium abundance: 12 + log10(He+/H+), based on the emission line flux ratio Heλ5876/H  α from Galactic and extragalactic H  ii regions compiled from the literature. Based on this calibrator, we explore for the first time the helium abundance in a large sample of H  ii regions located in galaxies representative of the nearby Universe from the CALIFA survey. Furthermore, this calibrator allows us to explore the variations of the helium abundance with respect to the oxygen abundance. The observed trends are in agreement with a change in the chemical enrichment with mass/oxygen abundance similar to the one observed due to the inside-out model in a MW-galaxy (highlighting the connection between resolved and global trends in galaxies). Our calibrator provides an empirical proxy to estimate the helium abundance at kpc scales as well as to constrain chemical evolutionary models. [ABSTRACT FROM AUTHOR]

This series of papers aims at understanding the formation and evolution of non-barred disc galaxies. We use the new spectro-photometric decomposition code, c2d , to separate the spectral information of bulges and discs of a statistically representative sample of galaxies from the CALIFA survey. Then, we study their stellar population properties analysing the structure-independent datacubes with the Pipe3D algorithm. We find a correlation between the bulge-to-total (B / T) luminosity (and mass) ratio and galaxy stellar mass. The B / T mass ratio has only a mild evolution with redshift, but the bulge-to-disc (B / D) mass ratio shows a clear increase of the disc component since redshift z < 1 for massive galaxies. The mass–size relation for both bulges and discs describes an upturn at high galaxy stellar masses (log (M ⋆/M⊙) > 10.5). The relation holds for bulges but not for discs when using their individual stellar masses. We find a negligible evolution of the mass–size relation for both the most massive (⁠|$\log {(M_{\star \rm ,b,d}/{\rm M}_{\odot })} \gt 10$|⁠) bulges and discs. For lower masses, discs show a larger variation than bulges. We also find a correlation between the Sérsic index of bulges and both galaxy and bulge stellar mass, which does not hold for the disc mass. Our results support an inside-out formation of nearby non-barred galaxies, and they suggest that (i) bulges formed early-on and (ii) they have not evolved much through cosmic time. However, we find that the early properties of bulges drive the future evolution of the galaxy as a whole, and particularly the properties of the discs that eventually form around them. [ABSTRACT FROM AUTHOR]

The processes that regulate star formation are essential to understand how galaxies evolve. We present the relation between star formation rate density, ΣSFR , and hydrostatic mid-plane pressure, P h, for 4260 star-forming regions of kpc size located in 96 galaxies included in the EDGE-CALIFA survey covering a wide range of stellar masses and morphologies. We find that these two parameters are tightly correlated, showing a smaller scatter in comparison to other star-forming relations. A power law, with a slightly sublinear index, is a good representation of this relation. Its residuals show a significant anticorrelation with both stellar age and metallicity whereas the total stellar mass may also play a secondary role in shaping the ΣSFR– P h relation. For actively star-forming regions, we find that the effective feedback momentum per unit stellar mass (p */ m *), measured from the P h/ΣSFR  ratio increases with P h. The median value of this ratio for all the sampled regions is larger than the expected momentum just from supernovae explosions. Morphology of the galaxies, including bars, does not seem to have a significant impact in the ΣSFR– P h relation. Our analysis indicates that local ΣSFR self-regulation comes mainly from momentum injection to the interstellar medium from supernovae explosions. However, other mechanisms in disc galaxies may also play a significant role in shaping the ΣSFR at kpc scales. Our results also suggest that P h is the main parameter that modulates star formation at kpc scales, rather than individual components of the baryonic mass. [ABSTRACT FROM AUTHOR]

We present a new characterization of the relations between star-formation rate, stellar mass, and molecular gas mass surface densities at different spatial scales across galaxies (from galaxy-wide to kpc scales). To do so, we make use of the largest sample combining spatially resolved spectroscopic information with CO observations, provided by the Extragalactic Database for Galaxy Evolution (EDGE)–Calar Alto Legacy Integral Field Area (CALIFA) survey, together with new single-dish CO observations obtained by the Atacama Pathfinder Experiment (APEX). We show that these relations are the same at the different scales explored, sharing the same distributions for the explored data, with similar slope, intercept, and scatter (when characterized by a simple power law). From this analysis, we propose that these relations are the projection of a single relation between the three properties that follows a distribution described well by a line in three-dimensional parameter space. Finally, we show that observed secondary relations between the residuals and the parameters considered are explained fully by the correlation between the uncertainties, and therefore have no physical origin. We discuss these results in the context of the hypothesis of self-regulation of the star-formation process. [ABSTRACT FROM AUTHOR]

MUSE-based emission-line maps of the spiral galaxy NGC 4030 reveal the existence of unresolved sources with forbidden line emission enhanced with respect to those seen in its own H  ii regions. This study reports our efforts to detect and isolate these objects and identify their nature. Candidates are first detected as unresolved sources on an image of the second principal component of the H β, [O  iii ] 5007, H α, [N  ii ] 6584, [S  ii ] 6716, 6731 emission-line data cube, where they stand out clearly against both the dominant H  ii region population and the widespread diffuse emission. The intrinsic emission is then extracted accounting for the highly inhomogeneous emission-line 'background' throughout the field of view. Collisional to recombination line ratios like [S  ii ]/H α, [N  ii ]/H α, and [O  i ]/H α tend to increase when the background emission is corrected for. We find that many (but not all) sources detected with the principal component analysis have properties compatible with supernova remnants (SNRs). Applying a combined [S  ii ]/H α and [N  ii ]/H α classification criterion leads to a list of 59 sources with SNR-like emission lines. Many of them exhibit conspicuous spectral signatures of SNRs around 7300 Å, and a stacking analysis shows that these features are also present, except weaker, in other cases. At nearly 30 Mpc, these are the most distant SNRs detected by optical means to date. We further report the serendipitous discovery of a luminous (MV ∼ −12.5), blue, and variable source, possibly associated with a supernova impostor. [ABSTRACT FROM AUTHOR]

We present a novel method to retrieve the chemical structure of galaxies using integral field spectroscopy data through the stellar Metallicity Distribution Function (MDF). This is the probability distribution of observing stellar populations having a metallicity Z. We apply this method to a set of 550 galaxies from the CALIFA survey. We present the behaviour of the MDF as a function of the morphology, the stellar mass, and the radial distance. We use the stellar metallicity radial profiles retrieved as the first moment of the MDF, as an internal test for our method. The gradients in these radial profiles are consistent with the known trends: they are negative in massive early-type galaxies and tend to positive values in less massive late-type ones. We find that these radial profiles may not convey the complex chemical structure of some galaxy types. Overall, low mass galaxies (log  M ⋆/M⊙ ≤ 10) have broad MDFs (⁠|$\sigma _Z\sim 1.0\,$|  dex), with unclear dependence on their morphology. However this result is likely affected by under-represented bins in our sample. On the other hand, massive galaxies (log  M ⋆/M⊙ ≥ 11) have systematically narrower MDFs (⁠|$\sigma _Z\le 0.2\,$|  dex). We find a clear trend whereby the MDFs at rk / Re > 1.5 have large variance. This result is consistent with sparse SFHs in medium/low stellar density regions. We further find there are multimodal MDFs in the outskirts (⁠|$\sim 18\,$|  per cent) and the central regions (⁠|$\sim 40\,$|  per cent) of galaxies. This behaviour is linked to a fast chemical enrichment during early stages of the SFH, along with the posterior formation of a metal-poor stellar population. [ABSTRACT FROM AUTHOR]

Context. We study the spatially resolved properties of 343 elliptical galaxies with the Mapping Nearby Galaxies at the Apache Point Observatory (MaNGA) survey. Aims. Our goal is to understand the fundamental processes of formation and quenching of elliptical galaxies. Methods. We used the DESI Legacy Imaging Surveys for accurate morphological classification. Based on integrated spectroscopic properties and colors, we classified seven classes of elliptical galaxies. We inferred the stellar age and metallicity gradients out to a 1.5 effective radius (Reff) of classical "red and dead", recently quenched, and blue star-forming ellipticals (CLEs, RQEs, and BSFs), corresponding to 73%, 10%, and 4% of the sample, respectively. Additionally, we reconstructed their global and radial histories of star formation and mass growth. Results. The mass- and luminosity-weighted age gradients of CLEs are nearly flat or mildly negative, with small differences between both ages. The respective metallicity gradients are negative (∇log[Zmw] = −0.11−0.08+0.07 dex/Reff and ∇log[Zlw] = −0.11−0.07+0.06 dex/Reff, respectively), being flatter as the mass is smaller. The more massive CLEs formed stars earlier and quenched faster than the less massive ones. The CLEs show a weak inside-out growth and a clear inside-out quenching. They finished their quenching globally 3.8  ±  1.2 Gyr ago on average, with quenching time-scales of 3.4  ±  0.8 Gyr. At M⋆ < 1011 M⊙, the age and Z gradients of the RQEs and BSFs are flatter than those of the CLEs, but with larger scatters. They show very weak inside-out growth and quenching, which is slow and not even completed at z ∼ 0 for the BSFs. Instead, the massive RQEs show an outside-in quenching and positive gradients in the luminosity-weighted age and stellar metallicities. The RQEs of all masses quenched 1.2 ± 0.9 Gyr ago on average. Conclusions. Our results for the CLEs are consistent with a two-phase scenario where their inner parts formed by an early and coeval dissipative collapse with a consequent burst of star formation and further quenching, whereas the outer parts continued their assembly, likely by dry mergers. We also discuss some evolutionary scenarios for the RQE and BSF galaxies that would agree with the generic results. [ABSTRACT FROM AUTHOR]

We use the stellar kinematics for 2458 galaxies from the MaNGA survey to explore a universal fundamental plane (UFP) described by the equation , defined by the logarithms of effective radius, Re; the surface brightness within Re, Ie; the dynamical mass-to-light ratio within Re, Ye; and the total velocity parameter at Re, , where is the rotation velocity and is the velocity dispersion. The surface brightness is within Re, Ie, and the dynamical mass-to-light ratio is within Re, ϒe. We use sophisticated Schwarzschild dynamical models for a subsample of 300 galaxies from the CALIFA survey to calibrate the universal fundamental plane. This calibration allows us to propose both (i) a parameterization to estimate the difficult-to-measure averaged dynamical mass-to-light ratio within Re, , once the internal kinematics, surface brightness, and effective radius are known; and (ii) a new, more robust dynamical mass proxy consistent with dynamical models within 0.09 dex. We reproduce the relation between the dynamical mass and the stellar mass in the inner regions of galaxies with lower scatter. We use the estimated from our analysis to explore the UFP with the MaNGA data set. We find that all galaxies, from spheroids to disks, follow the UFP with a scatter significantly smaller (0.05 dex) than the one reported for the fundamental plane (∼0.09 dex) and comparable with Tully–Fisher studies (∼0.05 dex), but for a wider range of galaxy types. We also confirm that spheroidal and spiral galaxies follow the same M⋆–S0.5 scaling relation, with lower scatter than the and ones, which is in agreement with previous studies found in the literature. [ABSTRACT FROM AUTHOR]

AT 2018cow was the nearest and best-studied example of a new breed of extragalactic, luminous, and rapidly evolving transient. Both the progenitor systems and explosion mechanisms of these rapid transients remain a mystery – the energetics, spectral signatures, and time-scales make them challenging to interpret in established classes of supernovae and tidal disruption events. The rich, multiwavelength data set of AT 2018cow has still left several interpretations viable to explain the nature of this event. In this paper, we analyze integral-field spectroscopic data of the host galaxy, CGCG 137-068, to compare environmental constraints with leading progenitor models. We find the explosion site of AT 2018cow to be very typical of core-collapse supernovae (known to form from stars with M ZAMS ∼ 8−25 M⊙), and infer a young stellar population age at the explosion site of few × 10 Myr, at slightly sub-solar metallicity. When comparing to expectations for exotic intermediate-mass black hole (IMBH) tidal disruption events, we find no evidence for a potential host system of the IMBH. In particular, there are no abrupt changes in metallicity or kinematics in the vicinity of the explosion site, arguing against the presence of a distinct host system. The proximity of AT 2018cow to strong star formation in the host galaxy makes us favour a massive stellar progenitor for this event. [ABSTRACT FROM AUTHOR]

We present a new catalogue of H  ii regions based on the integral field spectroscopy (IFS) data of the extended CALIFA and PISCO samples. The selection of H  ii regions was based on two assumptions: a clumpy structure with high contrast of H α emission and an underlying stellar population comprising young stars. The catalogue provides the spectroscopic information of 26 408 individual regions corresponding to 924 galaxies, including the flux intensities and equivalent widths of 51 emission lines covering the wavelength range between 3745 and 7200 Å. To our knowledge, this is the largest catalogue of spectroscopic properties of H  ii regions. We explore a new approach to decontaminate the emission lines from diffuse ionized gas contribution. This diffuse gas correction was estimated to correct every emission line within the considered spectral range. With the catalogue of H  ii regions corrected, new demarcation lines are proposed for the classical diagnostic diagrams. Finally, we study the properties of the underlying stellar populations of the H  ii regions. It was found that there is a direct relationship between the ionization conditions on the nebulae and the properties of stellar populations besides the physicals condition on the ionized regions. [ABSTRACT FROM AUTHOR]

Estimating the bar pattern speed (Ωbar) is one of the main challenges faced in understanding the role of stellar bars in galaxy dynamical evolution. This work aims to characterize different uncertainty sources affecting the Tremaine–Weinberg (TW) method to study the correlation between bar and galaxies physical parameters. We use a sample of 15 MaNGA SDSS-IV galaxies and 3 CALIFA galaxies from Aguerri et al. We studied the errors related with (i) galaxy centre determination, (ii) disc position angle (PA) emphasizing the difficulties triggered by outer non-axisymmetric structures besides the bar, (iii) the slits length, and (iv) the spatial resolution. In average, the PA uncertainties range |$\sim 15 {{\ \rm per\ cent}}$|⁠ , the slit length |$\sim 9 {{\ \rm per\ cent}}$| and the centring error |$\sim 5 {{\ \rm per\ cent}}$|⁠. Reducing the spatial resolution increases the sensitivity to the PA error. Through Monte Carlo simulations, we estimate the probability distribution of the |$\mathcal {R}$| bar speed parameter. The present sample is composed of seven slow, four fast, and seven ultrafast bars, with no trend with morphological types. Although uncertainties and low sample numbers may mask potential correlations between physical properties, we present a discussion of them: we observe an anticorrelation of Ωbar with the bar length and the stellar mass, suggesting that massive galaxies tend to host longer and slower bars. We also observe a correlation of the molecular gas fraction with |$\mathcal {R}$|⁠ , and a weak anticorrelation with Ωbar, suggesting that bars rotate slower in gaseous discs. Confirmation of such trends awaits future studies. [ABSTRACT FROM AUTHOR]

We present a 2D chemical evolution code applied to a Milky Way type Galaxy, incorporating the role of spiral arms in shaping azimuthal abundance variations, and confront the predicted behaviour with recent observations taken with integral field units. To the usual radial distribution of mass, we add the surface density of the spiral wave and study its effect on star formation and elemental abundances. We compute five different models: one with azimuthal symmetry which depends only on radius, while the other four are subjected to the effect of a spiral density wave. At early times, the imprint of the spiral density wave is carried by both the stellar and star formation surface densities; conversely, the elemental abundance pattern is less affected. At later epochs, however, differences among the models are diluted, becoming almost indistinguishable given current observational uncertainties. At the present time, the largest differences appear in the star formation rate and/or in the outer disc (R ≥ 18 kpc). The predicted azimuthal oxygen abundance patterns for t ≤ 2 Gyr are in reasonable agreement with recent observations obtained with VLT/MUSE for NGC 6754. [ABSTRACT FROM AUTHOR]

We study the global star formation rate (SFR) versus stellar mass (M *) correlation, and the spatially resolved SFR surface density (ΣSFR) versus stellar mass surface density (Σ*) correlation, in a sample of ∼2000 galaxies from the MaNGA MPL-5 survey. We classify galaxies and spatially resolved areas into star forming and retired according to their ionization processes. We confirm the existence of a star-forming main sequence (SFMS) for galaxies and spatially resolved areas, and show that they have the same nature, with the global as a consequence of the local one. The latter presents a bend below a limit Σ* value, ≈3 × 107 M |$\odot$|  kpc−2, which is not physical. Using only star-forming areas (SFAs) above this limit, a slope and a scatter of ≈1 and ≈0.27 dex are determined. The retired galaxies/areas strongly segregate from their respective SFMSs, by ∼−1.5 dex on average. We explore how the global/local SFMSs depend on galaxy morphology, finding that for star-forming galaxies and SFAs, there is a trend to lower values of star formation activity with earlier morphological types, which is more pronounced for the local SFMS. The morphology not only affects the global SFR due to the diminish of SFAs with earlier types, but also affects the local SF process. Our results suggest that the local SF at all radii is established by some universal mechanism partially modulated by morphology. Morphology seems to be connected to the slow aging and sharp decline of the SF process, and on its own it may depend on other properties as the environment. [ABSTRACT FROM AUTHOR]

The star formation main sequence (SFMS) is a tight relation between the galaxy star formation rate (SFR) and its total stellar mass (M ⋆). Early-type galaxies (ETGs) are often considered as low-SFR outliers of this relation. We study, for the first time, the separated distribution in the SFR versus M ⋆ of bulges and discs of 49 ETGs from the CALIFA survey. This is achieved using c2d , a new code to perform spectrophotometric decompositions of integral field spectroscopy data cubes. Our results reflect that: (i) star formation always occurs in the disc component and not in bulges; (ii) star-forming discs in our ETGs are compatible with the SFMS defined by star-forming galaxies at z ∼ 0; (iii) the star formation is not confined to the outskirts of discs, but it is present at all radii (even where the bulge dominates the light); (iv) for a given mass, bulges exhibit lower sSFR than discs at all radii; and (v) we do not find a deficit of molecular gas in bulges with respect to discs for a given mass in our ETGs. We speculate our results favour a morphological quenching scenario for ETGs. [ABSTRACT FROM AUTHOR]

We present optical photometry and spectroscopy of the Type II supernova ASASSN-14jb, together with Very Large Telescope (VLT) Multi Unit Spectroscopic Explorer (MUSE) integral field observations of its host galaxy and a nebular-phase spectrum. This supernova, in the nearby galaxy ESO 467-G051 (z = 0.006), was discovered and followed-up by the all-sky automated survey for supernovae (ASAS-SN). We obtained well-sampled las cumbres network (LCOGTN) BVgri and Swiftw2m1w1ubv optical, near-UV/optical light curves, and several optical spectra in the early photospheric phases. The transient ASASSN-14jb exploded ∼2 kpc above the star-forming disk of ESO 467-G051, an edge-on disk galaxy. The large projected distance from the disk of the supernova position and the non-detection of any H II region in a 1.4 kpc radius in projection are in conflict with the standard environment of core-collapse supernova progenitors and suggests the possible scenario that the progenitor received a kick in a binary interaction. We present analysis of the optical light curves and spectra, from which we derived a distance of 25 ± 2 Mpc using state-of-the-art empirical methods for Type II SNe, physical properties of the SN explosion (56Ni mass, explosion energy, and ejected mass), and properties of the progenitor; namely the progenitor radius, mass, and metallicity. Our analysis yields a 56Ni mass of 0.0210  ±  0.0025 M⊙, an explosion energy of ≈0.25 × 1051 ergs, and an ejected mass of ≈6 M⊙. We also constrained the progenitor radius to be R* = 580  ±  28 R⊙ which seems to be consistent with the sub-Solar metallicity of 0.3  ±  0.1 Z⊙ derived from the supernova Fe II λ5018 line. The nebular spectrum constrains strongly the progenitor mass to be in the range 10–12 M⊙. From the Spitzer data archive we detect ASASSN-14jb ≈330 days past explosion and we derived a total dust mass of 10−4 M⊙ from the 3.6 μm and 4.5 μm photometry. Using the FUV, NUV, BVgri,Ks, 3.6 μm, and 4.5 μm total magnitudes for the host galaxy, we fit stellar population synthesis models, which give an estimate of M* ≈ 1 × 109 M⊙, an age of 3.2 Gyr, and a SFR ≈0.07 M⊙ yr−1. We also discuss the low oxygen abundance of the host galaxy derived from the MUSE data, having an average of 12 + log(O/H) = 8.27+0.16−0.20 12 + log (O / H) = 8. 27 − 0.20 + 0.16 $ 12+\log\mathrm{(O/H)} = 8.27^{+0.16}_{-0.20} $ using the O3N2 diagnostic with strong line methods. We compared it with the supernova spectra, which is also consistent with a sub-Solar metallicity progenitor. Following recent observations of extraplanar H II regions in nearby edge-on galaxies, we derived the metallicity offset from the disk, being positive, but consistent with zero at 2σ, suggesting enrichment from disk outflows. We finally discuss the possible scenarios for the unusual environment for ASASSN-14jb and conclude that either the in-situ star formation or runaway scenario would imply a low-mass progenitor, agreeing with our estimate from the supernova nebular spectrum. Regardless of the true origin of ASASSN-14jb, we show that the detailed study of the environment roughly agree with the stronger constraints from the observation of the transient. [ABSTRACT FROM AUTHOR]

We present a pilot study aimed to identify large-scale galaxy properties that could play a role in activating a quiescent nucleus. To do so, we compare the properties of two isolated nearby active galaxies and their non-active twins selected from the Calar Alto Legacy Integral Field Area (CALIFA) survey. This pilot sample includes two barred and two unbarred galaxies. We characterize the stellar and ionized gas kinematics and also their stellar content. We obtain simple kinematic models by fitting the full stellar and ionized gas velocity fields and just the approaching or receding sides. We find that the analysed active galaxies present lopsided discs and higher values of the global stellar angular momentum (λ R ) than their non-active twins. This could be indicating that the stellar discs of the AGN gained angular momentum from the inflowing gas that triggered the nuclear activity. The inflow of gas could have been produced by a twisted disc instability in the case of the unbarred AGN, and by the bar in the case of the barred AGN. In addition, we find that the central regions of the studied active galaxies show older stellar populations than their non-active twins. The next step is to statistically explore these galaxy properties in a larger sample of twin galaxies. [ABSTRACT FROM AUTHOR]

Context. Integral field spectroscopy (IFS) provides detailed information about galaxy kinematics at high spatial and spectral resolution, and the disentanglement of the gaseous and stellar components is a key step in the analysis of the data. Aims. We study how the use of several stellar-subtraction methods and line fitting approaches can affect the derivation of the main kinematic parameters (velocity and velocity dispersion fields) of the ionized gas component. Methods. The target of this work is the nearby galaxy NGC 2906, observed with the MUSE instrument at the Very Large Telescope (VLT). A sample of twelve spectra is selected from the inner (nucleus) and outer (spiral arms) regions, characterized by different ionization mechanisms. We compare three different methods to subtract the stellar continuum (FIT3D, STARLIGHT and pPXF), combined with one of the following stellar libraries: MILES, STELIB and GRANADA+MILES. Results. The choice of the stellar-subtraction method is the most important ingredient affecting the derivation of the gas kinematics, followed by the choice of the stellar library and by the line-fitting approach. In our data, typical uncertainties in the observed wavelength and width of the Hα and [NII] lines are of the order of ⟨δλ⟩rms ∼ 0.1 Å and ⟨δσ⟩rms ∼ 0.2 Å (i.e., ∼5 and 10 km s−1, respectively). The results obtained from the [NII] line seem to be slightly more robust, as it is less affected by stellar absorption than Hα. All methods considered yield statistically consistent measurements once a mean systemic contribution Δλ¯ = Δσ¯ = 0.2 ΔMUSE Δ λ ¯ = Δ σ ¯ = 0.2 Δ MUSE $ \Delta \bar\lambda = \Delta \bar\sigma = 0.2\,\Delta_{\mathrm{MUSE}} $ is added in quadrature to the line-fitting errors, where ΔMUSE = 1.1 Å ∼50 km s−1, which denotes the instrumental resolution of the MUSE spectra. Conclusions. Although the subtraction of the stellar continuum is critical in order to recover line fluxes, any method (including none) can be used to measure the gas kinematics, as long as an additional component, Δλ¯ = Δσ¯ = 0.2 ΔMUSE Δ λ ¯ = Δ σ ¯ = 0.2 Δ MUSE $ \Delta \bar\lambda = \Delta \bar\sigma = 0.2\,\Delta_{\mathrm{MUSE}} $ , is added to the error budget. [ABSTRACT FROM AUTHOR]

Galaxies are complex systems made up of different structural components such as bulges, discs, and bars. Understanding galaxy evolution requires unveiling, independently, their history of stellar mass and metallicity assembly. We introduce c2d, a new algorithm to perform spectro-photometric multicomponent decompositions of integral field spectroscopy (IFS) datacubes. The galaxy surface-brightness distribution at each wavelength (quasi-monochromatic image) is fitted using GASP2D, a 2D photometric decomposition code. As a result, c2d provides both a characteristic one-dimensional spectra and a full datacube with all the spatial and spectral information for every component included in the fit. We show the basic steps of the c2d spectro-photometric fitting procedure, tests on mock datacubes demonstrating its reliability, and a first application of c2d to a sample of three early-type galaxies (ETGs) observed within the Calar Alto Legacy Integral Field Area survey. The resulting datacubes from c2d are processed through the Pipe3D pipeline obtaining both the stellar populations and ionized gas properties of bulges and discs. This paper presents an overview of the potential of c2d  +  Pipe3D to unveil the formation and evolution of galaxies. [ABSTRACT FROM AUTHOR]

We present a detailed exploration of the stellar mass versus gas-phase metallicity relation (MZR) using integral field spectroscopy data obtained from ∼1000 galaxies observed by the SAMI galaxy survey. These spatially resolved spectroscopic data allow us to determine the metallicity within the same physical scale (R eff) for different calibrators. The shape of the MZ relations is very similar between the different calibrators, while there are large offsets in the absolute values of the abundances. We confirm our previous results derived using the spatially resolved data provided by the CALIFA and MaNGA surveys: (1) we do not find any significant secondary relation of the MZR with either the star formation rate (SFR) or the specific SFR (SFR/ M *) for any of the calibrators used in this study, based on the analysis of the individual residuals; (2) if there is a dependence with the SFR, it is weaker than the reported one (rc ∼ −0.3), it is confined to the low-mass regime (M * < 109 M⊙) or high-SFR regimes, and it does not produce any significant improvement in the description of the average population of galaxies. The aparent disagreement with published results based on single-fibre spectroscopic data could be due to (i) the interpretation of the secondary relation itself; (ii) the lower number of objects sampled at the low-mass regime by the current study; or (iii) the presence of extreme star-forming galaxies that drive the secondary relation in previous results. [ABSTRACT FROM AUTHOR]