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13 págs.; 10 figs.; 4 tabs., We present the intensive spectroscopic follow up of the Type Ia supernova (SN Ia) 2014J in the starburst galaxy M82. Twenty-seven optical spectra have been acquired from 2014 January 22 to September 1 with the Isaac Newton and William Herschel Telescopes. After correcting the observations for the recession velocity of M82 and for MilkyWay and host galaxy extinction, we measured expansion velocities from spectral line blueshifts and pseudo-equivalent width of the strongest features in the spectra, which gives an idea on how elements are distributedwithin the ejecta.We position SN 2014J in the Benetti, Branch et al. andWang et al. diagrams. These diagrams are based on properties of the Si II features and provide dynamical and chemical information about the SN ejecta. The nearby SN 2011fe, which showed little evidence for reddening in its host galaxy, is shown as a reference for comparisons. SN 2014J is a border-line object between the Core-normal and Broad-line groups, which corresponds to an intermediate position between low-velocity gradient and high-velocity gradient objects. SN 2014J follows the R(Si II)-Δm15 correlation, which confirms its classification as a relatively normal SN Ia. Our description of the SN Ia in terms of the evolution of the pseudo-equivalent width of various ions as well as the position in the various diagrams put this specific SN Ia into the overall sample of SN Ia. 2016 The Authors ; Published by Oxford University Press on behalf of the Royal Astronomical Society, Based on service observations (programme SW2014a08) made with the WHT, and on discretionary and Spanish CAT service observations made with the INT, both operated on the island of La Palma by the ING in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofısica de Canarias. Support for LG and MH 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. LG acknowledges support by CONICYT through FONDECYT grant 3140566. Support for MEMR and MM is provided by DGICYT grant AYA2010-21887-C04-02. This work is partially funded by DGICYT grant AYA2013-47742-C4-4-P. JIG-H, HL and JAR-M acknowledge financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) under the 2011 Severo Ochoa programme MINECO SEV-2011-0187 JIG-H also acknowledge the 2013 Ramon y Cajal programme MINECO RYC-2013-14875, and the Spanish ministry project MINECO AYA2014-56359-P. EAC acknowledges the support of the STFC.

11 págs.; 6 figs.; 4 tabs., We analyse a time series of optical spectra of SN 2014J from almost two weeks prior to maximum to nearly four months after maximum. We perform our analysis using the SYNOW code, which is well suited to track the distribution of the ions with velocity in the ejecta. We show that almost all of the spectral features during the entire epoch can be identified with permitted transitions of the common ions found in normal supernovae (SNe) Ia in agreement with previous studies. We show that 2014J is a relatively normal SN Ia. At early times the spectral features are dominated by Si II, S II, Mg II, and Ca II. These ions persist to maximum light with the appearance of Na I and Mg I. At later times iron-group elements also appear, as expected in the stratified abundance model of the formation of normal Type Ia SNe. We do not find significant spectroscopic evidence for oxygen, until 100 d after maximum light. The +100 d identification of oxygen is tentative, and would imply significant mixing of unburned or only slight processed elements down to a velocity of 6000 kms-1. Our results are in relatively good agreement with other analyses in the infrared. We briefly compare SN 2011fe to SN 2014J and conclude that the differences could be due to different central densities at ignition or differences in the C/O ratio of the progenitors. 2016 The Authors ; Published by Oxford University Press on behalf of the Royal Astronomical Society, The work has been supported in part by support for programme HST-GO-12948.004-A provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. EB acknowledges support from a Carl Bush Fellowship from the University of Oklahoma. Support for LG 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. LG acknowledges support by CONICYT through FONDECYT grant 3140566. JIGH acknowledges financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) under the 2011 Severo Ochoa programme MINECO SEV-2011-0187, and the 2013 Ramon y Cajal programme MINECO RYC-2013-14875, and the Spanish ministry project MINECO AYA2014-56359-P. ID acknowledges MINECOFEDER grant AYA2011-22460.

Based on observations collected at the German-Spanish Astronomical Center, Calar Alto, jointly operated by the Max-Planck-Institut für Astronomie Heidelberg and the Instituto de Astrofísica de Andalucía (CSIC )., CALIFA Team: et al., We study, for the first time in a statistically significant and well-defined sample, the relation between the outer-disk ionized-gas metallicity gradients and the presence of breaks in the surface brightness profiles of disk galaxies. Sloan Digital Sky Survey (SDSS) g′- and r′-band surface brightness, (g′ - r′) color, and ionized-gas oxygen abundance profiles for 324 galaxies within the Calar Alto Legacy Integral Field Area (CALIFA) survey are used for this purpose. We perform a detailed light-profile classification, finding that 84% of our disks show down- or up-bending profiles (Type II and Type III, respectively), while the remaining 16% are well fitted by one single exponential (Type I). The analysis of the color gradients at both sides of this break shows a U-shaped profile for most Type II galaxies with an average minimum (g′ - r′) color of ∼ 0.5mag and an ionized-gas metallicity flattening associated with it only in the case of low-mass galaxies. Comparatively, more massive systems show a rather uniform negative metallicity gradient. The correlation between metallicity flattening and stellar mass for these systems results in p-values as low as 0.01. Independent of the mechanism having shaped the outer light profiles of these galaxies, stellar migration or a previous episode of star formation in a shrinking star-forming disk, it is clear that the imprint in their ionized-gas metallicity was different for low- and high-mass Type II galaxies. In the case of Type III disks, a positive correlation between the change in color and abundance gradient is found (the null hypothesis is ruled out with a p-value of 0.02), with the outer disks of Type III galaxies with masses ≤10 M′ showing a weak color reddening or even a bluing. This is interpreted as primarily due to a mass downsizing effect on the population of Type III galaxies that recently experienced an enhanced inside-out growth., R. A. Marino is funded by the Spanish program of International Campus of Excellence Moncloa (CEI).We acknowledge support from the Plan Nacional de Investigación y Desarrollo funding programs, AyA2010-15081, AyA2012-30717 and AyA2013-46724P, of Spanish Ministerio de Economía y Competitividad (MINECO). A.G.d.P. acknowledges the support from the FP7 Marie Curie Actions of the European Commission, via the Initial Training Network DAGAL under REA grant agreement PITNGA-2011-289313. C.C.-T. thanks the support of the Spanish Ministerio de Educación, Cultura y Deporte by means of the FPU fellowship program. C.J.W. acknowledges support through the Marie Curie Career Integration Grant 303912. Support for L.G. is provided by the Ministry of Economy, Development, and Tourism’s Millennium Science Initiative through grant IC 120009, awarded to The Millennium Institute of Astrophysics, MAS. L.G. acknowledges support by CONICYT through FONDECYT grant 3140566. S.F.S. thanks the CONACYT-125180 and DGAPA-IA100815 projects for providing him support in this study. J.M.A. acknowledges support from the European Research Council Starting Grant (SEDmorph; P.I. V. Wild). P.P. is supported by FCT through the Investigador FCT Contract No. IF/01220/2013 and POPH/FSE (EC) by FEDER funding through the program COMPETE. He also acknowledges support by FCT under project FCOMP-01-0124-FEDER-029170 (Reference FCT PTDC/FISAST/3214/2012), funded by FCT-MEC (PIDDAC) and FEDER (COMPETE).

Astronomy and Astrophysics 584 (2015): A87 reproduced with permission from Astronomy & Astrophysics, © ESO, The star formation rate (SFR) is one of the main parameters used to analyze the evolution of galaxies through time. The need for recovering the light reprocessed by dust commonly requires the use of low spatial resolution far-infrared data. Recombination line luminosities provide an alternative, although uncertain dust-extinction corrections based on narrowband imaging or long-slit spectroscopy have traditionally posed a limit to their applicability. Integral field spectroscopy (IFS) is clearly the way to overcome this kind of limitation. Aims. We obtain integrated Hα, ultraviolet (UV) and infrared (IR)-based SFR measurements for 272 galaxies from the CALIFA survey at 0.005, The authors also thank the support from the Plan Nacional de Investigación y Desarrollo funding programs, AYA2012-30717 and AyA2013-46724P, of Spanish Ministerio de Economía y Competitividad (MINECO). P.G.P.-G. acknowledges support from the AYA2012-30717 and AYA2012-31277. J.I.P. acknowledges financial support from the Spanish MINECO under grant AYA2010-21887-C04-01 and from Junta de Andalucía Excellence Project PEX2011-FQM7058. R.A.M. is funded by the Spanish program of International Campus of Excellence Moncloa (CEI). M.A.P.T. acknowledges support from the Spanish MINECO through grant AYA2012-38491-C02-02. A.d.O. acknowledge financial support from the Spanish grant AYA2013-42227-P. 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. J.M.G. acknowledges support from the Fundação para a Ciência e a Tecnologia (FCT) through the Fellowship SFRH/BPD/66958/2009 from FCT (Portugal) and POPH/FSE (EC) by FEDER funding through the program Programa Operacional de Factores de competitividade (COMPETE). J.M.G. also acknowledges support by FCT under project FCOMP-01-0124-FEDER-029170 (Reference FCT PTDC/FIS-AST/3214/2012), funded by FCTMEC (PIDDAC) and FEDER (COMPETE)

arXiv:1510.07084v1.-- Infante, Leopoldo et al., We searched for z ≲ 7 Lyman-break galaxies in the optical-to-mid-infrared Hubble Frontier Field and associated parallel field observations of the strong-lensing cluster MACS J0416-2403. We discovered 22 candidates, of which 6 lie at z ≲ 9 and 1 lies at z ≲ 10. Based on the Hubble and Spitzer photometry, all have secure photometric redshifts and a negligible probability of being at lower redshifts according to their peak-probability ratios, . This substantial increase in the number of known high-redshift galaxies allows a solid determination of the luminosity function (LF) at z ≲ 8. The number of high-z candidates in the parallel field is considerably higher than that in the Abell 2744 parallel field. Our candidates have median stellar masses of M, star formation rates (SFRs) of M yr, and SFR-weighted ages of . Finally, we are able to put strong constraints on the z = 7, 8, 9, and 10 LFs. One of the objects in the cluster field is a z ≃ 10 candidate, with a magnification of μ ∼ 20 ± 13. This object is likely the faintest z ∼ 10 object known to date, allowing a first look into the extreme faint end (L ∼ 0.04 L∗) of the z ∼ 10 LF (It is named >Tayna> in the Aymara language)., We acknowledge support from Basal-CATA PFB-06/2007 (LI, FEB, NL, SK, PT), FP7-SPACE-2012-ASTRODEEP-312725 (XS), NSFC grants 11103017 and 11233002 (XS), NASA through Hubble Fellowship grant HST-HF2-51334.01-A awarded by STScI (AZ), CONICYT-Chile grants FONDECYT 1141218 (FEB), gemini-conicyt 32120003 (FEB, NL), and “EMBIGGEN” Anillo ACT1101 (FEB), the Ministry of Economy, Development, and Tourism’s Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS (FEB), Spanish consolider project CAD2010-00064 and AYA2012-39475-C02-01 (JMD), the Brazilian funding agency-FAPESP pos-doc fellowship - process number 2014/11806-9 (AM) and CONICYT-Chile grant FONDECYT 3140542 (PT).

We have discovered an Ofpe/WN9 (WN11 following Smith et al.) star in the Sculptor spiral galaxy NGC 300, the first object of this class found outside the Local Group, during a recent spectroscopic survey of blue supergiant stars obtained at the ESO Very Large Telescope. The light curve over a 5 month period in late 1999 displays a variability at the 0.1 mag level. The intermediate-resolution spectra (3800-7200 Å) show a very close resemblance to the Galactic luminous blue variable (LBV) AG Carinae during minimum. We have performed a detailed non-LTE analysis of the stellar spectrum and have derived a chemical abundance pattern that includes H, He, C, N, O, Al, Si, and Fe, in addition to the stellar and wind parameters. The derived stellar properties and the He and N surface enrichments are consistent with those of other Local Group WN11 stars in the literature, suggesting a similar quiescent or post-LBV evolutionary status., W. G. gratefully acknowledges support for this research from the Chilean Center for Astrophysics (FONDAP 15010003). F. N. acknowledges Spanish MCYT PANAYA2000-1784 and Ramon y Cajal grants.

Wei Zheng et al., We report the discovery of 24 Lyman-break candidates at 7 ≲ z ≲ 10.5, in the Hubble Frontier Fields (HFF) imaging data of A2744 (z = 0.308), plus Spitzer/IRAC data and archival ACS data. The sample includes a triple image system with a photometric redshift of z ≃ 7.4. This high redshift is geometrically confirmed by our lens model corresponding to deflection angles that are 12% larger than the lower-redshift systems used to calibrate the lens model at z = 2.019. The majority of our high-redshift candidates are not expected to be multiply lensed given their locations in the image plane and the brightness of foreground galaxies, but are magnified by factors of 1.3-15, so that we are seeing further down the luminosity function than comparable deep-field imaging. It is apparent that the redshift distribution of these sources does not smoothly extend over the full redshift range accessible at z < 12, but appears to break above z = 9. Nine candidates are clustered within a small region of 20″ across, representing a potentially unprecedented concentration. Given the poor statistics, however, we must await similar constraints from the additional HFF clusters to properly examine this trend. The physical properties of our candidates are examined using the range of lens models developed for the HFF program by various groups including our own, for a better estimate of underlying systematics. Our spectral-energy-distribution fits for the brightest objects suggest stellar masses of ≃ 109 M O, star formation rates of ≃ 4 M ⊙ yr-1, and a typical formation redshift of z ≲ 19., X.S. acknowledges support from FP7-SPACE-2012-ASTRODEEP-312725, and NSFC grants 11103017 and 11233002. Support for A.Z. is provided by NASA through Hubble Fellowship grant HST-HF-51334.01-A awarded by STScI. F.E.B. acknowledges support from Basal-CATA PFB-06/2007, CONICYT-Chile grants (FONDECYT 1141218, ALMA-CONICYT 31100004, Gemini-CONICYT 32120003, Anillo ACT1101), and the Millennium Institute of Astrophysics (Project IC120009). J.M.D. acknowledges support from the Spanish consolider project CAD2010-00064 and AYA2012-39475-C02-01.