The ionized gas in active galaxies in the MaNGA survey

Apresentamos mapas para as distribuições de fluxo nas linhas de emissão, excitação, densidade superficial de massa de gás ionizado e taxa de formação estelar para 150 Núcleos Ativos de Galáxias (AGN) observados com o SDSS-IV MaNGA, comparando-os com os obtidos para uma amostra controle de galáxias não ativas. Descobrimos que, para os AGNs early-type, o gás ionizado é mais concentrado na região nuclear quando comparado com as galáxias de controle, enquanto que para as galáxias late-type a distribuição de gás é semelhante à das galáxias de controle, sendo distribuída mais uniformemente por todo a galáxia. A massa total de gás ionizado varia de ≈ 104M a ≈ 109M. A principal diferença entre os AGNs e os controles está na densidade superficial central de massa de gás ionizado { dentro de 0,2R Re (raio efetivo) { que é maior para os AGNs do que para os controles, com uma diferença maior observada para as early-types do que para as late-types. Essa diferença entre os AGNs e os controles é maior para os AGNs de maior luminosidade e torna-se mais baixa à medida que a luminosidade dos AGNs diminui. Calculamos os perfis espaciais médios da densidade superficial de massa de gás ionizado e mostramos que eles decrescem mais rapidamente com o raio para os AGNs do que para os controles dentro de 0,4R e no caso dos AGNs de maior luminosidade (L([OIII]λ 5007) ≥ 3:8x1040 erg s-¹)sendo semelhantes aos dos controles além deste raio e para AGNs de menor luminosidade. Calculamos a taxa de formação estelar SFR nas regiões HII do corpo das galáxias hospedeiras de AGN e controles, encontrando uma diferença somente para as galáxias early-type, para as quais as que têm AGN apresentam um pequeno excesso no valor da SFR em relação às galáxias de controle. Estudamos também a relação entre o raio RNLR (onde NLR é a sigla para representar a Narrow Line Region) da região ionizada pelo AGN e a luminosidade L[OIII] do AGN e encontramos uma correlação positiva. Esta correlação indica que a região de gás ionizado pelo AGN cresce com a luminosidade do mesmo, de forma semelhante à encontrada previamente para a Broad Line Region e por outros autores para a NLR. Finalmente, obtivemos a metalicidade do gás para as regiões HII no corpo da galáxia que, extrapolada para a região central, mostra um bom acordo com a metalicidade derivada para o gás da NLR a partir de calibrações em termos de razões de linhas de emissão obtidas a partir de modelos de fotoionização.We present maps for the ionized gas density and star formation rates for 150 Active Galactic Nuclei (AGN) observed with SDSS-IV MaNGA, and compare them with those of a control sample of nonactive galaxies. We nd that, for the early-type AGN, the ionized gas is more concentrated in the nuclear region, when compared with the controls, while for the late-type galaxies the gas distribution is similar to that in the controls, being spread throughout the galaxies. The total ionized gas mass ranges from ≈ 104M to ≈109M . The main difference between the AGN and controls is on the central ionized gas surface mass density { within 0.2Re (effective radius) { that is larger for the AGN than for the controls, with a larger difference observed for the early-type than for the late-type galaxies. This di#erence between the AGN and controls is highest for the highest luminosity AGN and becomes lower as the AGN luminosity decreases. We have calculated average proles of the gas surface mass density and show that they are steeper in the AGN when compared to controls within the inner 0.4Re for the highest luminosity AGN (L([OIII]λ 5007) ≥ 3:8 x 1040 erg s1), being similar to those of the controls beyond this radius and for lower luminosity AGN. We have obtained the star-formation rate SFR for the HII regions along the body of the AGN host galaxies and controls, nding a di#erence only for the early-type galaxies, for which the AGN hosts present a small excess in the integrated SFR as compared to the control galaxies. We have also investigated the relation between the radius of the region ionized by the AGN RNLR (where NLR stands for Narrow- Line Region) and the AGN luminosity L[OIII], finding a positive correlation. This correlation indicates that the radius of the region ionized by the AGN increases with its luminosity, similarly to previously found for the Broad-Line Region and for the NLR itself in previous studies. Finally, we have derived the gas metallicity for the HII regions over the body of the galaxy that, when extrapolated to the central region, shows good agreement with the gas metalicity of the NLR obtained from calibrations in terms of emission-line ratios derived from photoionization models

The 13th Data Release of the Sloan Digital Sky Survey : first spectroscopic data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in 2014 July. It pursues three core programs: the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2), Mapping Nearby Galaxies at APO (MaNGA), and the Extended Baryon Oscillation Spectroscopic Survey (eBOSS). As well as its core program, eBOSS contains two major subprograms: the Time Domain Spectroscopic Survey (TDSS) and the SPectroscopic IDentification of ERosita Sources (SPIDERS). This paper describes the first data release from SDSS-IV, Data Release 13 (DR13). DR13 makes publicly available the first 1390 spatially resolved integral field unit observations of nearby galaxies from MaNGA. It includes new observations from eBOSS, completing the Sloan Extended QUasar, Emission-line galaxy, Luminous red galaxy Survey (SEQUELS), which also targeted variability-selected objects and X-ray-selected objects. DR13 includes new reductions of the SDSS-III BOSS data, improving the spectrophotometric calibration and redshift classification, and new reductions of the SDSS-III APOGEE-1 data, improving stellar parameters for dwarf stars and cooler stars. DR13 provides more robust and precise photometric calibrations. Value-added target catalogs relevant for eBOSS, TDSS, and SPIDERS and an updated red-clump catalog for APOGEE are also available. This paper describes the location and format of the data and provides references to important technical papers. The SDSS web site, http://www.sdss.org, provides links to the data, tutorials, examples of data access, and extensive documentation of the reduction and analysis procedures. DR13 is the first of a scheduled set that will contain new data and analyses from the planned ∼6 yr operations of SDSS-IV

The fourteenth data release of the Sloan Digital Sky Survey : first spectroscopic data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014–2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as “The Cannon”; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V

Gas-phase metallicity determinations in nearby AGNs with SDSS-IV MaNGA : evidence of metal-poor accretion

We derive the metallicity (traced by the O/H abundance) of the narrow-line region (NLR) of 108 Seyfert galaxies as well as radial metallicity gradients along their galaxy discs and of these of a matched control sample of no active galaxies. In view of that, observational data from the SDSS-IV MaNGA survey and strong emission-line calibrations taken from the literature were considered. The metallicity obtained for the NLRs was compared to the value derived from the extrapolation of the radial oxygen abundance gradient, obtained from H II region estimates along the galaxy disc, to the central part of the host galaxies. We find that, for most of the objects (∼ 80 per cent), the NLR metallicity is lower than the extrapolated value, with the average difference ( D ) between these estimates ranging from 0.16 to 0.30 dex. We suggest that D is due to the accretion of metal-poor gas to the AGN that feeds the nuclear supermassive black hole (SMBH), which is drawn from a reservoir molecular and/or neutral hydrogen around the SMBH. Additionally, we look for correlations between D and the electron density (Ne), [O III]λ5007, and H α luminosities, extinction coefficient (AV) of the NLRs, as well as the stellar mass (M∗) of the host galaxies. Evidence of an inverse correlation between the D and the parameters Ne, M∗, and Av was found

The first 62 AGN observed with SDSS-IV MaNGA – IV. Gas excitation and star formation rate distributions

We present maps of the ionized gas flux distributions, excitation, star formation rate (SFR), surface mass density ΣH+, and obtain total values of SFR and ionized gas masses M for 62 active galactic nuclei (AGN) observed with SDSS-IV MaNGA and compare them with those of a control sample of 112 non-active galaxies. The most luminous AGN – with L([OIII]λ5007)≥3.8×1040ergs−1, and those hosted by earlier type galaxies are dominated by Seyfert excitation within 0.2 effective radius Re from the nucleus, surrounded by LINER excitation or transition regions, while the less luminous and hosted by later-type galaxies show equally frequent LINER and Seyfert excitation within 0.2Re. The extent R of the region ionized by the AGN follows the relation R∝L([OIII])0.5 – as in the case of the broad-line region. The SFR distribution over the region ionized by hot stars is similar for AGN and controls, while the integrated SFR – in the range 10−3–10 M⊙ yr−1 is also similar for the late-type subsample, but higher in the AGN for 75 per cent of the early-type subsample. We thus conclude that there is no signature of AGN quenching star formation in the body of the galaxy in our sample. We also find that 66 per cent of the AGN have higher ionized gas masses M than the controls – in the range 105–3 × 107 M⊙ – while 75 per cent of the AGN have higher ΣH+ within 0.2Re than the control galaxie

The first 62 AGN observed with SDSS-IV MaNGA – III : stellar and gas kinematics

We investigate the effects of active galactic nuclei (AGN) on the gas kinematics of their host galaxies, using MaNGA data for a sample of 62 AGN hosts and 109 control galaxies (inactive galaxies). We compare orientation of the line of nodes (kinematic position angle – PA) measured from the gas and stellar velocity fields for the two samples. We found that AGN hosts and control galaxies display similar kinematic PA offsets between gas and stars. However, we note that AGN have larger fractional velocity dispersion σ differences between gas and stars [σfrac = (σgas − σstars)/σstars] when compared to their controls, as obtained from the velocity dispersion values of the central (nuclear) pixel (2. 5 diameter). The AGN have a median value of σfrac of AGN = 0.04, while the median value for the control galaxies is CTR =−0.23. 75 per cent of the AGN show σfrac > −0.13, while 75 per cent of the normal galaxies show σfrac < −0.04, thus we suggest that the parameter σfrac can be used as an indicator of AGN activity. We find a correlation between the [OIII]λ5007 luminosity and σfrac for our sample. Our main conclusion is that the AGN already observed with MaNGA are not powerful enough to produce important outflows at galactic scales, but at 1–2 kpc scales, AGN feedback signatures are always present on their host galaxies

The first 62 AGNs observed with SDSS-IV MaNGA : I. Their characterization and definition of a control sample

We report the characterization of the first 62 Mapping Nearby Galaxies at the Apache Point Observatory active galactic nuclei (AGNs) hosts and the definition of a control sample of non-active galaxies. This control sample was selected in order to match the AGN hosts in terms of stellar mass, redshift, visual morphology and inclination. The stellar masses are in the range 9.4 < log M/M < 11.5, and most objects have redshifts ≤0.08. The AGN sample is mostly comprised low-luminosity AGN, with only 17 ‘strong AGN’ with L([O III]λ5007 Å) ≥ 3.8 × 1040 erg s−1. The inner 1–3 kpc of the control sample galaxies are dominated by the oldest (≥ 4Gyr) component, with a small contribution of intermediate age and young stars (<940 Myr). Examining the relationship between the stellar population properties and L([O III]), we find that with increasing L([O III]), the AGN exhibit a decreasing contribution from the oldest stellar population relative to control galaxies and an increasing contribution from the younger components (∼40 Myr).We also find a correlation of the mean age differences (AGN–control) with L([O III]), in the sense that more luminous AGNs are younger than the control objects, while the low-luminosity AGNs are older. These results support a connection between the growth of the galaxy bulge via formation of new stars and the growth of the Supermassive Black Hole via accretion in the AGN phase

The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates

Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period: Tree-inventory plots established between 1934 and 2019. Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm. Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types