99 research outputs found

    The EDGE-CALIFA survey: The local and global relations between Σ\Sigma_\ast , ΣSFR\Sigma_{SFR} and Σmol\Sigma_{mol} that regulate star-formation

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    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 EDGE-CALIFA survey, together with new single dish CO observations obtained by APEX. We show that those relations are the same at the different explored scales, 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 well described by a line in the three-dimension parameter space. Finally, we show that observed secondary relations between the residuals and the considered parameters are fully explained 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.Comment: 21 pages,7 figures, accepted to be published in the MNRA

    Bar pattern speeds in CALIFA galaxies: I. Fast bars across the Hubble sequence

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    The bar pattern speed (Ωb\Omega_{\rm b}) is defined as the rotational frequency of the bar, and it determines the bar dynamics. Several methods have been proposed for measuring Ωb\Omega_{\rm b}. The non-parametric method proposed by Tremaine \& Weinberg (1984; TW) and based on stellar kinematics is the most accurate. This method has been applied so far to 17 galaxies, most of them SB0 and SBa types. We have applied the TW method to a new sample of 15 strong and bright barred galaxies, spanning a wide range of morphological types from SB0 to SBbc. Combining our analysis with previous studies, we investigate 32 barred galaxies with their pattern speed measured by the TW method. The resulting total sample of barred galaxies allows us to study the dependence of Ωb\Omega_{\rm b} on galaxy properties, such as the Hubble type. We measured Ωb\Omega_{\rm b} using the TW method on the stellar velocity maps provided by the integral-field spectroscopy data from the CALIFA survey. Integral-field data solve the problems that long-slit data present when applying the TW method, resulting in the determination of more accurate Ωb\Omega_{\rm b}. In addition, we have also derived the ratio R\cal{R} of the corotation radius to the bar length of the galaxies. According to this parameter, bars can be classified as fast (R\cal{R} 1.4).Forallthegalaxies,1.4). For all the galaxies, \cal{R}iscompatiblewithintheerrorswithfastbars.Wecannotruleout(at95 is compatible within the errors with fast bars. We cannot rule out (at 95\%level)thefastbarsolutionforanygalaxy.Wehavenotobservedanysignificanttrendbetween level) the fast bar solution for any galaxy. We have not observed any significant trend between \cal{R}$ and the galaxy morphological type. Our results indicate that independent of the Hubble type, bars have been formed and then evolve as fast rotators. This observational result will constrain the scenarios of formation and evolution of bars proposed by numerical simulations.Comment: 17 pages, 10 figures, accepted for publication in A&

    (New) Bulgarian Enlighteners and Ambassadors? The Reinvention of National Identity in Times of Crisis

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    Drawing on empirical data from 37 Bulgarian students and young professionals in the UK, this article explores the intersection of the discourses produced by the European crises and migrants' national identity. In Bulgaria, the crisis narrative is embedded in the arguably never‐ending democratic transition, manifested in socio‐economic instability and political volatility. Simultaneously, “Brexit Britain” is enveloped in strong Eurosceptic sentiments, propelled by a combination of austerity measures and intensified Eastern European migratory flows. Both contexts subject Bulgarian migrants to stigmatizing representations. Looking at migrants' everyday practices, the data reveals that young Bulgarians draw on the related ideas of the “new” Enlightener and Ambassador to counterbalance negative discourses. Thus, the article explores the meanings and significance attributed to the Enlighteners and the Ambassadors, arguing that the participants engage in “social creativity” and “individual mobility” strategies that lead to reinvention of national identity

    Evaluating mating compatibility within fruit fly cryptic species complexes and the potential role of sex pheromones in pre-mating isolation

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    The study of sexual behavior and the identification of the signals involved in mate recognition between con-specifics are key components that can shed some light, as part of an integrative taxonomic approach, in delimitating species within species complexes. In the Tephritidae family several species complexes have received particular attention as they include important agricultural pests such as the Ceratitis fasciventris(Bezzi), Ceratitis anonae (Graham) and Ceratitis rosa Karsch (FAR) complex, the Bactrocera dorsalis(Hendel) complex and the Anastrepha fraterculus (Wiedemann) complex. Here the value and usefulness of a methodology that uses walk-in field cages with host trees to assess, under semi-natural conditions, mating compatibility within these complexes is reviewed, and the same methodology to study the role of chemical communication in pre-mating isolation among Anastrepha fraterculus populations is used. Results showed that under the same experimental conditions it was possible to distinguish an entire range of different outcomes: from full mating compatibility among some populations to complete assortative mating among others. The effectiveness of the methodology in contributing to defining species limits was shown in two species complexes: Anastrepha fraterculus and Bactrocera dorsalis, and in the case of the latter the synonymization of several established species was published. We conclude that walk-in field cages constitute a powerful tool to measure mating compatibility, which is also useful to determine the role of chemical signals in species recognition. Overall, this experimental approach provides a good source of information about reproductive boundaries to delimit species. However, it needs to be applied as part of an integrative taxonomic approach that simultaneously assesses cytogenetic, molecular, physiological and morphological traits in order to reach more robust species delimitations.Fil: Juárez, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Devescovi, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Brízová, Radka. Institute Of Organic Chemistry And Biochemistry; República ChecaFil: Bachmann, Guillermo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Segura, Diego Fernando. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kalinova, Blanka. Institute Of Organic Chemistry And Biochemistry; República ChecaFil: Fernandez, Patricia Carina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Ruiz, María Josefina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Yang, Jianquan. Fujian Agriculture and Forestry University; ChinaFil: Teal, Peter E. A.. No especifíca;Fil: Cáceres, Carlos. No especifíca;Fil: Vreysen, Marc J.B.. No especifíca;Fil: Hendrichs, Jorge. No especifíca;Fil: Vera, María Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentin

    CALIFA : a diameter-selected sample for an integral field spectroscopy galaxy survey

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    JMA acknowledges support from the European Research Council Starting Grant (SEDmorph; P.I. V. Wild).We describe and discuss the selection procedure and statistical properties of the galaxy sample used by the Calar Alto Legacy Integral Field Area (CALIFA) survey, a public legacy survey of 600 galaxies using integral field spectroscopy. The CALIFA "mother sample" was selected from the Sloan Digital Sky Survey (SDSS) DR7 photometric catalogue to include all galaxies with an r-band isophotal major axis between 45 '' and 79 : 2 '' and with a redshift 0 : 005 M-r > -23 : 1 and over a stellar mass range between 10(9.7) and 10(11.4) M-circle dot. In particular, within these ranges, the diameter selection does not lead to any significant bias against - or in favour of - intrinsically large or small galaxies. Only below luminosities of M-r = -19 (or stellar masses <10(9.7) M-circle dot) is there a prevalence of galaxies with larger isophotal sizes, especially of nearly edge-on late-type galaxies, but such galaxies form <10% of the full sample. We estimate volume-corrected distribution functions in luminosities and sizes and show that these are statistically fully compatible with estimates from the full SDSS when accounting for large-scale structure. For full characterization of the sample, we also present a number of value-added quantities determined for the galaxies in the CALIFA sample. These include consistent multi-band photometry based on growth curve analyses; stellar masses; distances and quantities derived from these; morphological classifications; and an overview of available multi-wavelength photometric measurements. We also explore different ways of characterizing the environments of CALIFA galaxies, finding that the sample covers environmental conditions from the field to genuine clusters. We finally consider the expected incidence of active galactic nuclei among CALIFA galaxies given the existing pre-CALIFA data, finding that the final observed CALIFA sample will contain approximately 30 Sey2 galaxies.Peer reviewe

    CALIFA, the Calar Alto Legacy Integral Field Area survey: I. Survey presentation

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    We present here the Calar Alto Legacy Integral Field Area (CALIFA) survey, which has been designed to provide a first step in this direction.We summarize the survey goals and design, including sample selection and observational strategy.We also showcase the data taken during the first observing runs (June/July 2010) and outline the reduction pipeline, quality control schemes and general characteristics of the reduced data. This survey is obtaining spatially resolved spectroscopic information of a diameter selected sample of 600\sim600 galaxies in the Local Universe (0.005< z <0.03). CALIFA has been designed to allow the building of two-dimensional maps of the following quantities: (a) stellar populations: ages and metallicities; (b) ionized gas: distribution, excitation mechanism and chemical abundances; and (c) kinematic properties: both from stellar and ionized gas components. CALIFA uses the PPAK Integral Field Unit (IFU), with a hexagonal field-of-view of \sim1.3\sq\arcmin', with a 100% covering factor by adopting a three-pointing dithering scheme. The optical wavelength range is covered from 3700 to 7000 {\AA}, using two overlapping setups (V500 and V1200), with different resolutions: R\sim850 and R\sim1650, respectively. CALIFA is a legacy survey, intended for the community. The reduced data will be released, once the quality has been guaranteed. The analyzed data fulfill the expectations of the original observing proposal, on the basis of a set of quality checks and exploratory analysis. We conclude from this first look at the data that CALIFA will be an important resource for archaeological studies of galaxies in the Local Universe.Comment: 32 pages, 29 figures, Accepted for publishing in Astronomy and Astrophysic

    Recrystallization of CaCO3 submicron magnetic particles in biological media

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    Background and Objectives: The development of magnetic theranostics is associated with the determination of the behavior of magnetic carriers in biosimilar media. In this work, we analyze the formation of different crystalline phases from magnetic mineral submicron calcium carbonate particles during incubation under conditions of cell cultivation in vitro for 3 days. The study of mineralmagneticsubmicron particles recrystallization was analyzed by XRD and electron scanning microscopy. The shape of calcium carbonate particles begins to change from elliptical to spherical under cell culture cultivations. As the amount of magnetite nanoparticle particles in calcium carbonate increases, the recrystallization process is faster with fallout of calcite, vaterite and magnetite phases. Materials and Methods: Scanning electron microscopy, processing of results using a self-written Python code, XRDwere utilized in this study. Results: The study of the process of recrystallization of magnetic mineral particles shows has shown that increasing the content of magnetic carriers leads to accelerated recrystallization of particles with simultaneous precipitation of calcite, vaterite and magnetite phases. Conclusion: Magnetic mineral submicron calcium carbonate particles are promising targets for theranostics with the self-destruction property in biological environments

    Investigating the link between inner gravitational potential and star-formation quenching in CALIFA galaxies

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    Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.It has been suggested that gravitational potential can have a significant role in suppressing star formation in nearby galaxies. To establish observational constraints on this scenario, we investigated the connection between the dynamics – taking the circular velocity curves (CVCs) as a proxy for the inner gravitational potential – and star formation quenching in 215 non-active galaxies across the Hubble sequence from the Calar Alto Legacy Integral Field Area (CALIFA) survey. Our results show that galaxies with similar CVCs tend to have a certain star-formation quenching pattern. To explore these findings in more details, we constructed kiloparsec(kpc)-resolved relations of the equivalent width of the Hα (WHα) versus the amplitude (Vc) and shape (β = dlnVc/dlnR) of the circular velocity at given radii. We find that the WHα − Vc is a declining relationship, where the retired regions of the galaxies (the ones with WHα values of below 3 Å) tend to have higher Vc. Concurrently, WHα − β is a bimodal relationship, which is characterised by two peaks: concentration of the star forming regions at a positive β (rising CVC) and a second concentration of the retired regions with a negative β (declining CVC). Our results show that both the amplitude of the CVC – driven by the mass of the galaxies – and its shape – which reflects the internal structure of the galaxies – play an important role in the quenching history of a galaxy. © V. Kalinova et al. 2022.DC acknowledges support by the Deutsche Forschungsgemeinschaft, DFG project number SFB956A. SFS acknowledges Conacyt projects CB-285080 and FC-2016-01 -1916, and PAPIIT-DGAPA IN100519. RGB and RGD acknowledge financial support from the State Agency for Research of the Spanish MCIU through the “Center of Excellence Severo Ochoa” award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709), and the projects AYA2016-77846-P and PID2019-109067-GB100. ER acknowledges the support of the Natural Sciences and Engineering Research Council of Canada (NSERC), funding reference number RGPIN-2017-03987. KK acknowledges deep gratitude to MPIfR in Bonn for the Guest Researchership 2013–2021. In this study, we made use of the data of the first legacy survey, the Calar Alto Legacy Integral Field Area (CALIFA) survey, based on observations made at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max Planck-Institut für Astronomie and the Instituto de Astrofísica de Andalucía (CSIC). This research made use of the open-source python packages as Astropy (Astropy Collaboration 2018), SciPy (Virtanen et al. 2020), NumPy (Harris et al. 2020), and Matplotlib (Hunter 2007).Peer reviewe

    Outer-disk reddening and gas-phase metallicities: The CALIFA connection

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    Astronomy and Astrophysics 585 (2016): A47 reproduced with permission from Astronomy & AstrophysicsWe 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 ≤1010 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 growthWe 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 CONIC YT 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
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