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© 2007. The American Astronomical Society. All rights reserved. Artículo firmado por 29 autores. GALEX (Galaxy Evolution Explorer) is a NASA Small Explorer, launched in 2003 April. We gratefully acknowledge NASA’s support for construction, operation, and science analysis for the GALEX mission, developed in cooperation with the Centre National d’Etudes Spatiales of France and the Korean Ministry of Science and Technology. A. G. d. P. is financed by the MAGPOP EU Marie Curie Research Training Network and partially by the Spanish Programma Nacional de Astronomía y Astrofísica under grants AYA2003-01676 and AYA2006-02358. This research has made use of the NASA/IPAC Extragalactic Database (NED). We acknowledge the use of the HyperLeda database (http://leda.univ-lyon1.fr). The Digitized Sky Surveys were produced at the Space Telescope Science Institute under US Government grant NAG W-2166. Funding for the SDSS and SDSS-II has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, the US Department of Energy, the National Aeronautics and Space Administration, the Japanese Monbukagakusho, the Max Planck Society, and the Higher Education Funding Council for England. Some images presented in this paper were obtained from the Multimission Archive at the Space Telescope Science Institute (MAST ). STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5- 26555. Support for MAST for non-HST data is provided by the NASA Office of Space Science via grant NAG5-7584 and by other grants and contracts. This research has made use of the NASA/ IPAC Infrared Science Archive. This publication makes use of data products from the Two Micron All Sky Survey., We have initiated a search for extended ultraviolet disk (XUV-disk) galaxies in the local universe. Here we compare GALEX UV and visible-NIR images of 189 nearby (D < 40 Mpc) S0-Sm galaxies included in the GALEX Atlas of Nearby Galaxies and present the first catalog of XUV-disk galaxies. We find that XUV-disk galaxies are surprisingly common but have varied relative (UV/optical) extent and morphology. Type 1 objects (≳20% incidence) have structured, UV-bright/optically faint emission features in the outer disk, beyond the traditional star formation threshold. Type 2 XUV-disk galaxies (~10% incidence) exhibit an exceptionally large, UV-bright/optically low surface brightness (LSB) zone having blue UV-K_s outside the effective extent of the inner, older stellar population, but not reaching extreme galactocentric distance. If the activity occurring in XUV-disks is episodic, a higher fraction of present-day spirals could be influenced by such outer disk star formation. Type 1 disks are associated with spirals of all types, whereas Type 2 XUV-disks are predominantly found in late-type spirals. Type 2 XUV-disks are forming stars quickly enough to double their (currently low) stellar mass in the next Gyr (assuming a constant star formation rate). XUV-disk galaxies of both types are systematically more gas-rich than the general galaxy population. Minor external perturbation may stimulate XUV-disk incidence, at least for Type 1 objects. XUV-disks are the most actively evolving galaxies growing via inside-out disk formation in the current epoch, and may constitute a segment of the galaxy population experiencing significant, continued gas accretion from the intergalactic medium or neighboring objects., Programa Nacional de Astronomía y Astrofísica (PNAyA), España, US Government, Alfred P. Sloan Foundation, National Science Foundation (NSF), US Department of Energy, National Aeronautics and Space Administration, Japanese Monbukagakusho, Max Planck Society, Higher Education Funding Council for England, National Aeronautics and Space Administration (NASA), Office of Space Science (NASA), Unión Europea. FP6, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© ESO 2016. Artículo firmado por 22 autores. This study makes uses of the data provided by the Calar Alto Legacy Integral Field Area (CALIFA) survey (http://califa.caha.es/). CALIFA is the first legacy survey being performed at Calar Alto. The CALIFA collaboration would like to thank the IAA-CSIC and MPIA-MPG as major partners at the observatory, and CAHA itself, for the unique access to telescope time and support in manpower and infrastructures. The CALIFA collaboration also thanks the CAHA staff for their dedication to this project. E.P.M., J.M.V., C.K., S.P., and J.I.P. acknowledge support from the Spanish MICINN through grants AYA2010-21887-C04-01 and AYA2013-47742-C4-1-P and the Junta de Andalucía for grant EXC/2011 FQM-7058. R.G.B., R.G.D., and E.P. acknowledge support from grants AYA2014-57490-P and JA-FQM-2828. Support for L.G. is provided by the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS. L.G. acknowledges support by CONICYT through FONDECYT grant 3140566. This research made use of python (http://www.python.org), of Matplotlib (Hunter 2007), a suite of open-source python modules that provides a framework for creating scientific plots. We also thank Dr. Christophe Morisset for many discussions and constructive comments that have helped to improve the original manuscript., Context. The study of the integrated properties of star-forming galaxies is central to understand their formation and evolution. Some of these properties are extensive and therefore their analysis require totally covering and spatially resolved observations. Among these properties, metallicity can be defined in spiral discs by means of integral field spectroscopy (IFS) of individual H II regions. The simultaneous analysis of the abundances of primary elements, as oxygen, and secondary, as nitrogen, also provides clues about the star formation history and the processes that shape the build-up of spiral discs. Aims. Our main aim is to analyse simultaneously O/H and N/O abundance ratios in H II regions in different radial positions of the discs in a large sample of spiral galaxies to obtain the slopes and the characteristic abundance ratios that can be related to their integrated properties. Methods. We analysed the optical spectra of individual selected H II regions extracted from a sample of 350 spiral galaxies of the CALIFA survey. We calculated total O/H abundances and, for the first time, N/O ratios using the semi-empirical routine H II-C HI-MISTRY, which, according to Perez-Montero (2014, MNRAS, 441, 2663), is consistent with the direct method and reduces the uncertainty in the O/H derivation using [N II] lines owing to the dispersion in the O/H-N/O relation. Then we performed linear fittings to the abundances as a function of the de-projected galactocentric distances. Results. The analysis of the radial distribution both for O/H and N/O in the non-interacting galaxies reveals that both average slopes are negative, but a non-negligible fraction of objects have a flat or even a positive gradient (at least 10% for O/H and 4% for N/O). The slopes normalised to the effective radius appear to have a slight dependence on the total stellar mass and the morphological type, as late low-mass objects tend to have flatter slopes. No clear relation is found, however, to expla, Ministerio de Ciencia e Innovación (MICINN), Junta de Andalucía, Millennium Science Initiative (MSI) - Ministerio de Economía, Fomento y Turismo (Chile), Comisión Nacional de Investigación Científica y Tecnológica (CONICYT), Chile), Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT), Chile, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© ESO 2014. SFS thanks the director of CEFCA, M. Moles, for his sincere support. We thank the referee for his/her comments that have improved this manuscript. Based on observations made with ESO Telescopes at the Paranal Observatory under programme ID 60.A-9329. Support for L.G. and H.K. is provided by the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC12009, awarded to The Millennium Institute of Astrophysics, MAS. L.G. and H.K. acknowledge support by CONICYT through FONDECYT grants 3140566 and 3140563, respectively. S.F.S. acknowledges the Mexican National Council for Science and Technology (CONACYT) for financial support under the program Proyectos de Ciencia Básica. E.P. acknowledges funding from the Spanish MINECO grant AYA2010-15081. RA Marino was also funded by the Spanish programme of International Campus of Excellence Moncloa (CEI)., We present a study of the HII regions in the galaxy NGC 6754 from a two pointing mosaic comprising 197 637 individual spectra, using integral field spectroscopy recently acquired with the MUSE instrument during its Science Verification program. The data cover the entire galaxy out to similar to 2 effective radii (r(e)), sampling its morphological structures with unprecedented spatial resolution for a wide-field Integral Field Unit. A complete census of the HII regions limited by the atmospheric seeing conditions was derived, comprising 396 individual ionized sources. This is one of the largest and most complete catalogues of HII regions with spectroscopic information in a single galaxy. We use this catalogue to derive the radial abundance gradient in this SBb galaxy, finding a negative gradient with a slope consistent with the characteristic value for disk galaxies recently reported. The large number of HII regions allows us to estimate the typical mixing scale length (r(mix) similar to 0.4 r(e)), which sets strong constraints on the proposed mechanisms for metal mixing in disk galaxies, like radial movements associated with bars and spiral arms. We found evidence of an azimuthal variation in the oxygen abundance that may be connected with the radial migration. These results illustrate the unique capabilities of MUSE for the study of the enrichment mechanisms in Local Universe galaxies., Ministry of Economy, Development, and Tourism's Millennium Science Initiative, CONICYT through FONDECYT, Mexican National Council for Science and Technology (CONACYT), Spanish MINECO, Spanish programme of International Campus of Excellence Moncloa (CEI), ESO Telescopes at the Paranal Observatory, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© ESO 2014. We wish to thank Brad Gibson and Pierre Ocvirk for their constant advice. P.S.-B. acknowledges support from the Ramón y Cajal program, grant ATA2010-21322-C03-02 from the Spanish Ministry of Economy and Competitiveness (MINECO). F.F.R.O. acknowledges the Mexican National Council for Science and Technology (CONACYT) for financial support under the programme Estancias Posdoctorales y Sabáticas al Extranjero para la Consolidación de Grupos de Investigación, 2010-2012. We acknowledge financial support from the research projects under grants AYA2010-21887-C04-03, AYA2010-21322-C03-03 and AYA2010-15081 by the Spanish Ministerio de Ciencia e Innovación. J.F.-B. acknowledges support from the Ramón y Cajal Program, grants AYA2010-21322-C03-02 from the Spanish Ministry of Economy and Competitiveness (MINECO). R. A. M. is funded by the Spanish program of International Campues of Excellence Moncloa (CEI). C.J.W. acknowledges support through the Marie Curie Career Integration Grant 303912. I.M. acknowledges financial support from the Junta de Andalucía through projects PO8-TIC-03531 and TIC114, and the Spanish Ministry of Economy and Competitiveness (MINECO) through the project AYA2010-15169. We acknowledge the usage of the HyperLeda database (http://leda.univ-lyon1.fr). Based on observations collected at the Centro Astronómico Hispano-Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck Institut ur Astronomie and the Instituto de Astrofísica de Andalucía (CSIC). FCT/MCTES (Portugal) and POPH/FSE (EC). He acknowledges support by the Fundacao para a Ciencia e a Tecnologia (FCT) under project FCOMP-01-0124-FEDER-029170 (Reference FCT PTDC/FIS-AST/3214/2012), funded by FCT-MEC (PIDDAC) and FEDER (COMPETE). We also thanks the referee por his/her suggestions that have improved the final version of this paper., While studies of gasphase metallicity gradients in disc galaxies are common, very little has been done towards the acquisition of stellar abundance gradients in the same regions. We present here a comparative study of the stellar metallicity and age distributions in a sample of 62 nearly face-on, spiral galaxies with and without bars, using data from the CALIFA survey. We measure the slopes of the gradients and study their relation with other properties of the galaxies. We find that the mean stellar age and metallicity gradients in the disc are shallow and negative. Furthermore, when normalized to the effective radius of the disc, the slope of the stellar population gradients does not correlate with the mass or with the morphological type of the galaxies. In contrast to this, the values of both age and metallicity at similar to 2.5 scale lengths correlate with the central velocity dispersion in a similar manner to the central values of the bulges, although bulges show, on average, older ages and higher metallicities than the discs. One of the goals of the present paper is to test the theoretical prediction that non-linear coupling between the bar and the spiral arms is an efficient mechanism for producing radial migrations across significant distances within discs. The process of radial migration should flatten the stellar metallicity gradient with time and, therefore, we would expect flatter stellar metallicity gradients in barred galaxies. However, we do not find any difference in the metallicity or age gradients between galaxies with and without bars. We discuss possible scenarios that can lead to this lack of difference., Ramón y Cajal program from the Spanish Ministry of Economy and Competitiveness (MINECO), Mexican National Council for Science and Technology (CONACYT), Spanish Ministerio de Ciencia e Innovación, Spanish program of International Campus of Excellence Moncloa (CEI), Marie Curie Career Integration Grant, Junta de Andalucía, Spanish Ministry of Economy and Competitiveness (MINECO), Fundacao para a Ciencia e a Tecnologia (FCT), FCT-MEC (PIDDAC), FEDER (COMPETE), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© ESO, 2013. Artículo firmado por 33 autores. We would like to thank the anonymous referee for the review of our manuscript. The comments and suggestions helped to improve the content of the paper. R. A. Marino is funded by the Spanish program of International Campus of Excellence Moncloa (CEI). This study makes uses of the data provided by the Calar Alto Legacy Integral Field Area (CALIFA) survey (http://www.califa.caha.es). Based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck-Institut fur Astronomie and the Instituto de Astrofísica de Andalucía (CSIC). CALIFA is the first legacy survey being performed at Calar Alto. The CALIFA collaboration would like to thank the IAA-CSIC and MPIA-MPG, as major partners of the observatory, and CAHA itself, for the unique access to telescope time and support in manpower and infrastructures. The CALIFA collaboration also thanks the CAHA staff for their dedication to this project. We thank the Viabilidad, Diseño, Acceso y Mejora funding program, ICTS-2009-10, for supporting the initial developement of this project. S.F.S., F.F.R.O., and D. Mast thank the Plan Nacional de Investigación y Desarrollo funding programs, AYA2012-31935 of the Spanish Ministerio de Economía y Competitividad, for the support given to this project. S. F. S thanks the the Ramón y Cajal project RyC-2011-07590 of the spanish Ministerio de Economía y Competitividad, for the support giving to this project. F. F. R. O. acknowledges the Mexican National Council for Science and Technology (CONACYT) for financial support under the program Estancias Postdoctorales y Sabáticas al Extranjero para la Consolidación de Grupos de Investigación, 2010-2012. We acknowledge financial support for the ESTALLIDOS collaboration by the Spanish Ministerio de Ciencia e Innovación under grant AYA2010-21887-C04-03. BG-L also acknowledges support from the Spanish Ministerio de Economía y Competitividad (MINECO) u, The use of integral field spectroscopy is since recently allowing to measure the emission line fluxes of an increasingly large number of star-forming galaxies, both locally and at high redshift. Many studies have used these fluxes to derive the gas-phase metallicity of the galaxies by applying the so-called strong-line methods. However, the metallicity indicators that these datasets use were empirically calibrated using few direct abundance data points (T_e-based measurements). Furthermore, a precise determination of the prediction intervals of these indicators is commonly lacking in these calibrations. Such limitations might lead to systematic errors in determining the gas-phase metallicity, especially at high redshift, which might have a strong impact on our understanding of the chemical evolution of the Universe. The main goal of this study is to review the most widely used empirical oxygen calibrations, O3N2 and N2, by using new direct abundance measurements. We pay special attention to (1) the expected uncertainty of these calibrations as a function of the index value or abundance derived and (2) the presence of possible systematic offsets. This is possible thanks to the analysis of the most ambitious compilation of T_e-based H II regions to date. This new dataset compiles the Te-based abundances of 603 H II regions extracted from the literature but also includes new measurements from the CALIFA survey. Besides providing new and improved empirical calibrations for the gas abundance, we also present a comparison between our revisited calibrations with a total of 3423 additional CALIFA H II complexes with abundances derived using the ONS calibration from the literature. The combined analysis of T_e-based and ONS abundances allows us to derive their most accurate calibration to date for both the O3N2 and N2 single-ratio indicators, in terms of all statistical significance, quality, and coverage of the parameters space. In particular, we infer that these indicators, Unión Europea. FP7, Ministerio de Economía y Competitividad (MINECO), Campus de Excelencia internacional (CEI) Moncloa, Subprograma de diseño, viabilidad, acceso y mejora de Instalaciones Científicas y Técnicas Singulares (ICTS) (MINECO), Proyecto Ramón y Cajal (MINECO), Consejo Nacional de Ciencia y Tecnología (CONACYT), México, ESTALLIDOS Collaboration (MICINN), Acciones marie Curie (EU), People´s Program, DAGAL network, Programa PNAYA, Fundacao para a Ciencia e a Tecnologia (FCT), Portugal, FCT-MEC (PIDDAC), Portugal, FONDOS FEDER (COMPETE), UE, Proyecto Estancias Postdoctorales y Sabáticas al Extranjero para la Consolidación de Grupos de Investigación (CONACYT), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© EDP Sciencies. Based on observations made with the Isaac Newton Telescope operated on the island of La Palma by the Royal Greenwich Observatory in the Spanish Observatorio del Roque de los Muchachos of the Instituto Astrofísica. This research has been support in part by the grant No. PB96-0645 from the Spanish Programa Sectorial de Promoción General del Conocimiento., UCM1612+1308 is a new emission-line galaxy identified in the context of the Universidad Complutense de Madrid (UCM) survey. This object was classified as Blue Compact Galaxy (BCG) from photometric data. A detailed spectroscopic study from new optical observations is presented now. The physical conditions and chemical composition are derived. The ionic abundances yield to a metallicity of 0.23±0.01Z_⊙ and a very low nitrogen to oxygen abundances ratio, log (N/O)= -1.74±0.07, supporting a primary nucleosynthesis origin for the nitrogen. The same value has been obtained for the sulfur to oxygen ratio. The comparison of the helium abundance with the oxygen and nitrogen abundances evidences a quickly enrichment of oxygen produced by massive stars. The ionizing cluster has been analyzed yielding a relatively low ionization parameter, log bar Ū=-3, total number of stars, log N^* = 6.18, stellar mass, log M^* = 5.71 M_⊙, and gas mass log M_g = 7.42M_⊙. A lower limit of the dust mass, log M_dust = 5.65M_⊙, has been obtained from the IRAS fluxes. The observed data and derived parameters, when interpreted with the evolutionary synthesis models by Leitherer & Heckman (1995), point out to an instantaneous burst with an age of log t= 6.7yr., Programa Sectorial de Promoción General del Conocimiento (MEC), España, Ministerio de Educación y Cultura (MEC), España, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© ESO 2014. We would like to thank the Instituto de Astrofísica de Canarias for the excellent working conditions at the Observatorio del Roque de los Muchachos in La Palma. The support of the German BMBF and MPG, the Italian INFN, the Swiss National Fund SNF, and the Spanish MICINN is gratefully acknowledged. This work was also supported by the CPAN CSD2007-00042 and MultiDark CSD2009-00064 projects of the Spanish Consolider-Ingenio 2010 programme, by grant 127740 of the Academy of Finland, by the DFG Cluster of Excellence “Origin and Structure of the Universe”, by the Croatian Science Foundation Project 09/176, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, and by the Polish MNiSzW grant 745/N-HESSMAGIC/2010/0., Aims. HESS J1857+026 is an extended TeV gamma-ray source that was discovered by H. E. S. S. as part of its Galactic plane survey. Given its broadband spectral energy distribution and its spatial coincidence with the young energetic pulsar PSR J1856+0245, the source has been put forward as a pulsar wind nebula (PWN) candidate. MAGIC has performed follow-up observations aimed at mapping the source down to energies approaching 100 GeV in order to better understand its complex morphology. Methods. HESS J1857+026 was observed by MAGIC in 2010, yielding 29 h of good quality stereoscopic data that allowed us to map the source region in two separate ranges of energy. Results. We detected very-high-energy gamma-ray emission from HESS J1857+026 with a significance of 12 sigma above 150 GeV. The differential energy spectrum between 100 GeV and 13 TeV is described well by a power law function dN/dE = N-0(E/1TeV)(-Gamma) with N-0 = (5.37 +/- 0.44(stat) +/- 1.5(sys)) X 10(-12) (TeV-1 cm(-2) s(-1)) and Gamma = 2.16 +/- 0.07(stat) +/- 0.15(sys), which bridges the gap between the GeV emission measured by Fermi-LAT and the multi-TeV emission measured by H.E.S.S.. In addition, we present a detailed analysis of the energy-dependent morphology of this region. We couple these results with archival multiwavelength data and outline evidence in favor of a two-source scenario, whereby one source is associated with a PWN, while the other could be linked with a molecular cloud complex containing an HII region and a possible gas cavity., German BMBF, German MPG, Italian INFN, Swiss National Fund SNF, Spanish MICINN, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© ESO 2007. We thank the Spanish Plan Nacional de Astronomía program AYA2005-09413-C02-02, of the Spanish Ministery of Education and Science and the Plan Andaluz de Investigación of Junta de Andalucía as research group FQM322. M.V. thanks Matthias Steinmetz and the instrumentation group at the AIP for facilitating the construction of the PPak module and its integration into PMAS, the spectrograph used for this survey. We thank the referee, Prof. Dr. O’Dell, who helped us to improve the quality of this article with his valuable comments and suggestions, and his detailed check of the flux calibration., We present a low-resolution spectroscopic survey of the Orion nebula. The data are released for public use. We show the possible applications of this dataset analyzing some of the main properties of the nebula. Methods. We perform an integral field spectroscopy mosaic of an area of similar to 5' x 6' centered on the Trapezium region of the nebula, including the ionization front to the south-east. Analysis of the line fluxes and line ratios of both the individual and integrated spectra allowed us to determine the main characteristics of the ionization throughtout the nebula. Results. The final dataset comprises 8182 individual spectra, sampled in a circular area of similar to 2.7" diameter. The data can be downloaded as a single row-stacked spectra fit file plus a position table or as an interpolated datacube with a final sampling of 1.5"/pixel. The integrated spectrum across the field-of-view was used to obtain the main integrated properties of the nebula, including the electron density and temperature, the dust extinction, the Ha integrated flux (after correcting for dust reddening), and the main diagnostic line ratios. The individual spectra were used to obtain line intensity maps of the different detected lines. These maps were used to study the distribution of the ionized hydrogen, the dust extinction, the electron density and temperature, and the helium and oxygen abundance. All of them show a considerable degree of structure as already shown in previous studies. In particular, there is a tight relation between the helium and oxygen abundances and the ionization structure that cannot be explained by case B recombination theory. Simple arguments like partial ionization and dust mixed with the emitting gas may explain these relations. However a more detailed modeling is required, for which we provide the dataset., Spanish Plan Nacional de Astronomía program of the Spanish Ministery of Education and Science, Plan Andaluz de Investigación of Junta de Andalucía, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

This article has been accepted for publication in Monthly notices of the Royal Astronomical Society. © 2010 The Authors © 2010 RAS. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. We are grateful to the anonymous referee for his valuable comments which have led to an improvement in this paper. We acknowledge support from the Spanish Programa Nacional de Astronomía y Astrofísica under grants AYA2006-02358 and AYA2006-15698-C02-02. This work is partially funded by the Spanish MICINN under the Consolider-Ingenio 2010 Program grant CSD2006-00070: First Science with the GTC. ACM acknowledges support from the Juan de la Cierva Program financed by the Spanish MICINN. JPG acknowledges support from a University of Florida Alumni Fellowship and RG from NASA Grant LTSA NA65-11635. SFS thanks the sub-programs of Viabilidad, Diseño, Acceso y Mejora de ICTS ICTS-2009-10 and the PAI Proyecto de Excelencia P08-FWM-04319 and the funds of the PAI research group FQM360. SFS thanks the Spanish Plan Nacional de Astronomía program AYA2005-09413-C02-02., Physical properties of the star-forming regions in the local Luminous Compact Blue Galaxy (LCBG) NGC 7673 are studied in detail using 3D spectroscopic data taken with the PMAS fibre pack (PPAK) integral field unit at the 3.5-m telescope in the Centro Astronomico Hispano Aleman (CAHA). We derive integrated and spatially resolved properties such as extinction, star formation rate (SFR) and metallicity for this galaxy. Our data show an extinction map with maximum values located at the position of the main clumps of star formation showing small spatial variations [E(B - V)(t) = 0.12-0.21 mag]. We derive an H alpha-based SFR for this galaxy of 6.2 +/- 0.8M(circle dot) yr(-1) in agreement with the SFR derived from infrared and radio continuum fluxes. The star formation is located mainly in clumps A, B, C and F. Different properties measured in clump B make this region peculiar. We find the highest H alpha luminosity with an SFR surface density of 0.5 M-circle dot yr(-1) kpc(-2) in this clump. In our previous work, the kinematic analysis for this galaxy shows an asymmetrical ionized gas velocity field with a kinematic decoupled component located at the position of clump B. This region shows the absence of strong absorption features and the presence of a Wolf-Rayet stellar population indicating that this is a young burst of massive stars. Furthermore, we estimate a gas metallicity of 12 + log(O/H) = 8.20 +/- 0.15 (0.32 solar) for the integrated galaxy using the R23 index. The values derived for the different clumps with this method show small metallicity variations in this galaxy, with values in the range 8.12 (for clump A) to 8.23 (for clump B) for 12 + log(O/H). The analysis of the emission-line ratios discards the presence of any active galactic nuclei (AGN) activity or shocks as the ionization source in this galaxy. Between the possible mechanisms to explain the starburst activity in this galaxy, our 3D spectroscopic data support the scenario of an on-going interaction, Spanish Programa Nacional de Astronomía y Astrofísica, Spanish MICINN, University of Florida Alumni Fellowship, NASA, Viabilidad, Diseno, Acceso y Mejora de ICTS, PAI Proyecto de Excelencia, PAI, Spanish Plan Nacional de Astronomía, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© 2012. The American Astronomical Society. All rights reserved. We thank the anonymous referee for reviewing the manuscript, and for the comments and suggestions that helped to improve the content of the paper. We also thank Carmen Eliche Moral, Fabián Rosales Ortega, Judit Bakos, and Sheila Kannappan for helpful discussions. R. A. Marino was also funded by the Spanish program International Campus of Excellence Moncloa (CEI). We thank the Calar Alto Observatory for the allocation of the director's discretionary time to this program. We acknowledge support from the Spanish Programa Nacional de Astronomía y Astrofísica under grant AYA 2009-10368. We are also partially funded by the Spanish MICINN under the Consolider-Ingenio 2010 Program grant CSD2006-00070: First Science with the GTC. J.C.M.M. receives financial support from NASA JPL/Spitzer grant RSA 1374189. He also acknowledges support from the National Radio Astronomy Observatory, which is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, Caltech under NASA contract 1407. GALEX is a NASA Small Explorer launched in 2003 April. We gratefully acknowledge NASA's support for construction, operation, and scientific analysis of the GALEX mission. This research has made use of the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory, and the California Institute of Technology, under contract with the National Aeronautics and Space Administration. This paper makes use of the Sloan Digital Sky Survey data. Funding for the SDSS and SDSS-II has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, the U.S. Department of Energy, the National Aeronautics and Space Administration, the Japanese Monbukagakusho, the Max Planck Society, and, We present an analysis of the full bidimensional optical spectral cube of the nearby spiral galaxy NGC 5668, observed with the Pmas fiber PAcK Integral Field Unit (IFU) at the Calar Alto observatory 3.5 m telescope. We make use of broadband imaging to provide further constraints on the evolutionary history of the galaxy. This data set will allow us to improve our understanding of the mechanisms that drive the evolution of disks. We investigated the properties of 62 H II regions and concentric rings in NGC 5668 and derived maps in ionized-gas attenuation and chemical (oxygen) abundances. We find that while inward of r similar to 36 '' similar to 4.4 kpc similar to 0.36 (D-25/2) the derived O/H ratio follows the radial gradient typical of spiral galaxies, the abundance gradient beyond r similar to 36 '' flattens out. The analysis of the multi-wavelength surface brightness profiles of NGC 5668 is performed by fitting these profiles with those predicted by chemo-spectrophotometric evolutionary models of galaxy disks. From this, we infer a spin and circular velocity of lambda = 0.053 and nu(c) = 167 km s(-1), respectively. The metallicity gradient and rotation curve predicted by this best-fitting galaxy model nicely match the values derived from the IFU observations, especially within r similar to 36 ''. The same is true for the colors despite some small offsets and a reddening in the bluest colors beyond that radius. On the other hand, deviations of some of these properties in the outer disk indicate that a secondary mechanism, possibly gas transfer induced by the presence of a young bar, must have played a role in shaping the recent chemical and star formation histories of NGC 5668., Spanish program International Campus of Excellence Moncloa (CEI), Spanish Programa Nacional de Astronomía y Astrofísica, Spanish MICINN, NASA JPL/Spitzer, National Radio Astronomy Observatory, NASA, Alfred P. Sloan Foundation, National Science Foundation, U.S. Department of Energy, National Aeronautics and Space Administration, Japanese Monbukagakusho, Max Planck Society, Higher Education Funding Council for England, Astrophysical Research Consortium, American Museum of Natural History, Astrophysical Institute Potsdam, University of Basel, University of Cambridge, Case Western Reserve University, University of Chicago, Drexel University, Fermilab, Institute for Advanced Study, Japan Participation Group, Johns Hopkins University, Joint Institute for Nuclear Astrophysics, Kavli Institute for Particle Astrophysics and Cosmology, Korean Scientist Group, Chinese Academy of Sciences (LAMOST), Los Alamos National Laboratory, Max-Planck-Institute for Astronomy (MPIA), Max-Planck-Institute for Astrophysics (MPA), New Mexico State University, Ohio State University, University of Pittsburgh, University of Portsmouth, United States Naval Observatory, University of Washington, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

Conference on Astrophysical Dynamics, APR 14-16, 1999, Evora (Portugal), The characteristics of the halo gas and its interaction with the galactic disk in spiral galaxies are poorly known; this is particularly true for the warm neutral gas associated with HVCs and galactic chimneys. The detection of absorption features such as the NaI D or the CaII (H,K) lines is instrumental to study its detailed physical properties but requires very long integration times. In this work very deep optical spectra of NGC 604, the brightest giant HII region among the nearby spirals, are presented. The detection of two absorption components at LSR velocities -255 km/s and -20 km/s respectively, is reported; the first component is associated with the HII region. The inferred line width after deconvolution is 155 km/s; this large width is produced by the blending of the multiple absorption components produced by the diverse sources of internal motion (expanding shells and general turbulence). The radial velocity of the CaII absorption is slightly larger than the measured in the HII emission lines suggesting a possible flow of gas into the halo above the young star cluster. The large ratio x = W-lambda(NaI D-2)/W-lambda(CaIIK) = 0.7 indicates the probable presence of shocks which release Ca from the dust grains into the gas phase. The lower velocity component most likely trace galactic gas., Unidad Deptal. de Astronomía y Geodesia, Fac. de Ciencias Matemáticas, TRUE, pub

© ESO 2022. Artículo firmado por 48 autores. This work was carried out as part of the PHANGS collaboration. E. S., F. S., R. M. E., T. G. W. acknowledge funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No. 694343). S. C. O. G. and R. S. K. acknowledge financial support from the German Research Foundation (DFG) via the collaborative research centre (SFB 881, Project-ID 138713538) "The Milky Way System" (subprojects A1, B1, B2, and B8). They also acknowledge funding from the Heidelberg Cluster of Excellence "STRUCTURES" in the framework of Germany's Excellence Strategy (grant EXC-2181/1, Project-ID 390900948) and from the European Research Council via the ERC Synergy Grant "ECOGAL" (grant 855130). F. Bi, A. T. B., I. B. acknowledge funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No. 726384/Empire). C. E. acknowledges funding from the Deutsche Forschungsgemeinschaft (DFG) Sachbeihilfe, grant number BI1546/3-1. E. J. W. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - Project-ID 138713538 - SFB 881 ("The Milky Way System", subproject P2). J. M. D. K. and M. C. gratefully acknowledge funding from the Deutsche Forschungsgemeinschaft (DFG) through an Emmy Noether Research Group (grant number KR4801/1-1) and the DFG Sachbeihilfe (grant number KR4801/2-1) and from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme via the ERC Starting Grant MUSTANG (grant agreement number 714907). E. C. acknowledges support from ANID project Basal AFB-170002. K. K., O. E., and F. S. gratefully acknowledge funding from the German Research Foundation (DFG) in the form of an Emmy Noether Research Group (grant number KR4598/2-1, PI: Kreckel). E. W. acknowledges support from the DFG via SFB 881 "The Milky Way S, We present the PHANGS-MUSE survey, a programme that uses the MUSE integral field spectrograph at the ESO VLT to map 19 massive (9.4< log(M/M-circle dot)< 11.0) nearby (D less than or similar to 20 Mpc) star-forming disc galaxies. The survey consists of 168 MUSE pointings (1 ' by 1 ' each) and a total of nearly 15 x 10(6) spectra, covering similar to 1.5 x 10(6) independent spectra. PHANGS-MUSE provides the first integral field spectrograph view of star formation across different local environments (including galaxy centres, bars, and spiral arms) in external galaxies at a median resolution of 50 pc, better than the mean inter-cloud distance in the ionised interstellar medium. This 'cloud-scale' resolution allows detailed demographics and characterisations of H II regions and other ionised nebulae. PHANGS-MUSE further delivers a unique view on the associated gas and stellar kinematics and provides constraints on the star-formation history. The PHANGS-MUSE survey is complemented by dedicated ALMA CO(2-1) and multi-band HST observations, therefore allowing us to probe the key stages of the star-formation process from molecular clouds to H II regions and star clusters. This paper describes the scientific motivation, sample selection, observational strategy, data reduction, and analysis process of the PHANGS-MUSE survey. We present our bespoke automated data-reduction framework, which is built on the reduction recipes provided by ESO but additionally allows for mosaicking and homogenisation of the point spread function. We further present a detailed quality assessment and a brief illustration of the potential scientific applications of the large set of PHANGS-MUSE data products generated by our data analysis framework. The data cubes and analysis data products described in this paper represent the basis for the first PHANGS-MUSE public data release and are available in the ESO archive and via the Canadian Astronomy Data Centre., Unión Europea. Horizonte 2020, German Research Foundation (DFG) via the collaborative research centre, Heidelberg Cluster of Excellence "STRUCTURES" of Germany's Excellence Strategy, Deutsche Forschungsgemeinschaft (DFG) Sachbeihilfe German Research Foundation (DFG), Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), Deutsche Forschungsgemeinschaft (DFG) through an Emmy Noether Research Group German Research Foundation (DFG), DFG Sachbeihilfe German Research Foundation (DFG), German Research Foundation (DFG) in the form of an Emmy Noether Research Group, ANID project Basal, DFG German Research Foundation (DFG) European Commission, Programme National "Physique et Chimie du Milieu Interstellaire" (PCMI) of CNRS/INSU, INC/INP, CEA French Atomic Energy Commission, CNES Centre National D'etudes Spatiales, European Southern Observatory under ESO programmes, Space Telescope Science Institute under NASA Space Telescope Science Institute, NASA National Aeronautics & Space Administration (NASA), Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

The Large Magellanic Cloud (LMC) is the nearest laboratory for detailed studies on the formation and survival of complex organic molecules (COMs), including biologically important ones, in low-metallicity environments-typical of earlier cosmological epochs. We report the results of 1.2 mm continuum and molecular line observations of three fields in the star-forming region N 105 with the Atacama Large Millimeter/submillimeter Array. N 105 lies at the western edge of the LMC bar with ongoing star formation traced by H2O, OH, and CH3OH masers, ultracompact H ii regions, and young stellar objects. Based on the spectral line modeling, we estimated rotational temperatures, column densities, and fractional molecular abundances for 12 1.2 mm continuum sources. We identified sources with a range of chemical makeups, including two bona fide hot cores and four hot core candidates. The CH3OH emission is widespread and associated with all the continuum sources. COMs CH3CN and CH3OCH3 are detected toward two hot cores in N 105 together with smaller molecules typically found in Galactic hot cores (e.g., SO2, SO, and HNCO) with the molecular abundances roughly scaling with metallicity. We report a tentative detection of the astrobiologically relevant formamide molecule (NH2CHO) toward one of the hot cores; if confirmed, this would be the first detection of NH2CHO in an extragalactic subsolar metallicity environment. We suggest that metallicity inhomogeneities resulting from the tidal interactions between the LMC and the Small Magellanic Cloud might have led to the observed large variations in COM abundances in LMC hot cores.

We present the second dust continuum data release in the Census of High- and Medium-mass Protostars (CHaMP), expanding the methodology trialed in Pitts et al. to the entire CHaMP survey area (280 degrees < l < 300 degrees, - 4 degrees < b < + 2 degrees). This release includes maps of dust temperature (T-d), H-2 column density (NH2), gas-phase CO abundance, and temperature-density plots for every prestellar clump with Herschel coverage, showing no evidence of internal heating for most clumps in our sample. We show that CO abundance is a strong function of T-d and can be fit with a second-order polynomial in log-space, with a typical dispersion of a factor of 2-3. The CO abundance peaks at 20.0(-1.0)(+0.4) K with a value of 7.4(-0.3)(+0.2) x 10(-5) per H-2; the low T-d at which this maximal abundance occurs relative to laboratory results is likely due to interstellar UV bombardment in the largest survey fields. Finally, we show that, as predicted by theoretical literature and hinted at in previous studies of individual clouds, the conversion factor from integrated (CO)-C-12 line intensity ((ICO)-C-12) to NH2, the X-CO factor, varies as a broken power law in I-CO(12) with a transition zone between 70 and 90 K km s(-1). The X-CO function we propose has NH2 proportional to I-12CO(0.51) for I-12CO less than or similar to 70 K km s(-1) N-H2 proportional to I-12CO(2.3) for I-12CO greater than or similar to 90 K km s(-1) The high-I-12CO side should be generalizable with known adjustments for metallicity, but the influence of interstellar UV fields on the low-I-12CO side may be sample specific. We discuss how these results expand on previous works in the CHaMP series and help tie together observational, theoretical, and laboratory studies on CO over the past decade.

Understanding the escape of ionizing (Lyman continuum) photons from galaxies is vital for determining how galaxies contributed to reionization in the early universe. While directly detecting the Lyman continuum from high-redshift galaxies is impossible due to the intergalactic medium, low-redshift galaxies in principle offer this possibility but require observations from space. The first local galaxy for which Lyman continuum escape was found is Haro 11, a luminous blue compact galaxy at z = 0.02, where observations with the FUSE satellite revealed an escape fraction of 3.3%. However, the FUSE aperture covers the entire galaxy, and it is not clear from where the Lyman continuum is leaking out. Here we utilize Hubble Space Telescope/Cosmic Origins Spectrograph spectroscopy in the wavelength range 1100-1700 angstrom of the three knots (A, B, and C) of Haro 11 to study the presence of Ly alpha emission and the properties of intervening gas. We find that all knots have bright Ly alpha emission. UV absorption lines, originating in the neutral interstellar medium, as well as lines probing the ionized medium, are seen extending to blueshifted velocities of 500 km s(-1) in all three knots, demonstrating the presence of an outflowing multiphase medium. We find that knots A and B have large covering fractions of neutral gas, making LyC escape along these sightlines improbable, while knot C has a much lower covering fraction (less than or similar to 50%). Knot C also has the the highest Ly alpha escape fraction, and we conclude that it is the most likely source of the escaping Lyman continuum detected in Haro 11.

We present an analysis of the optical properties of three Ultra Luminous X-ray (ULX) sources identified in NGC 925. We use Integral field unit data from the George Mitchel spectrograph in the context of the Metal-THINGS survey. The optical properties for ULX-1 and ULX-3 are presented, while the spaxel associated with ULX-2 had a low S/N, which prevented its analysis. We also report the kinematics and dimensions of the optical nebula associated with each ULX using ancillary data from the PUMA Fabry-Perot spectrograph. A BPT analysis demonstrates that most spaxels in NGC 925 are dominated by star-forming regions, including those associated with ULX-1 and ULX-3. Using the resolved gas-phase metallicities, a negative metallicity gradient is found, consistent with previous results for spiral galaxies, while the ionization parameter tends to increase radially throughout the galaxy. Interestingly, ULX-1 shows a very low gas metallicity for its galactocentric distance, identified by two independent methods, while exhibiting a typical ionization. We find that such low gas metallicity is best explained in the context of the high-mass X-ray binary population, where the low-metallicity environment favors active Roche lobe overflows that can drive much higher accretion rates. An alternative scenario invoking accretion of a low-mass galaxy is not supported by the data in this region. Finally, ULX-3 shows both a high metallicity and ionization parameter, which is consistent with the progenitor being a highly accreting neutron star within an evolved stellar population region.

We present a multiwavelength study of the iconic Bubble Nebula (NGC 7635) and its ionizing star BD+60 degrees 2521 We obtained XMM Newton EPIC X-ray observations to search for. extended X-ray emission as in other similar wind-blown bubbles around massive stars. We also obtained San Pedro Madir spectroscopic observations with. the Manchester Echelle Spectrometer to study the dynamics of the Bubble Nebula. Although our EPIC observations are deep, we do not detect extended X-ray emission from this wind-blown bubble. On the other hand, BD+60 degrees 2522 is a bright X-ray source similar to other 0 stars. We used the stellar atmosphere code PolATR to characterize BD+60 degrees 2522 and found that this star is a young O-type star with stellar wind capable of producing a wirid-blown bubble that in principle could be filled with hot gas. We discussed our findings in line with recent ntirnerical simulations'proposing that the Bubble Nebula has been formed as the result of the fast motion of BD+60 degrees 2522 through the medium. Our kinematic study shows that the Bubble Nebula is composed by a series of nested shells, some showing blister-like structures, but with little signatures of hydrodynamical instabilities that would mix the material producing diffuse X-ray emission as seen in other wind-blown bubbles. Its morphology seems to be merely the result of projection effects of these different shells. © 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society