4,611 research outputs found

    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

    Additional value of screening for minor genes and copy number variants in hypertrophic cardiomyopathy

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    Introduction: Hypertrophic cardiomyopathy (HCM) is the most prevalent inherited heart disease. Next-generation sequencing (NGS) is the preferred genetic test, but the diagnostic value of screening for minor and candidate genes, and the role of copy number variants (CNVs) deserves further evaluation. Methods: Three hundred and eighty-seven consecutive unrelated patients with HCM were screened for genetic variants in the 5 most frequent genes (MYBPC3, MYH7, TNNT2, TNNI3 and TPM1) using Sanger sequencing (N = 84) or NGS (N = 303). In the NGS cohort we analyzed 20 additional minor or candidate genes, and applied a proprietary bioinformatics algorithm for detecting CNVs. Additionally, the rate and classification of TTN variants in HCM were compared with 427 patients without structural heart disease. Results: The percentage of patients with pathogenic/likely pathogenic (P/LP) variants in the main genes was 33.3%, without significant differences between the Sanger sequencing and NGS cohorts. The screening for 20 additional genes revealed LP variants in ACTC1, MYL2, MYL3, TNNC1, GLA and PRKAG2 in 12 patients. This approach resulted in more inconclusive tests (36.0% vs. 9.6%, p<0.001), mostly due to variants of unknown significance (VUS) in TTN. The detection rate of rare variants in TTN was not significantly different to that found in the group of patients without structural heart disease. In the NGS cohort, 4 patients (1.3%) had pathogenic CNVs: 2 deletions in MYBPC3 and 2 deletions involving the complete coding region of PLN. Conclusions: A small percentage of HCM cases without point mutations in the 5 main genes are explained by P/LP variants in minor or candidate genes and CNVs. Screening for variants in TTN in HCM patients drastically increases the number of inconclusive tests, and shows a rate of VUS that is similar to patients without structural heart disease, suggesting that this gene should not be analyzed for clinical purposes in HCM

    Entropy of a Kerr-de Sitter black hole due to arbitrary spin fields

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    The Newman-Penrose formalism is used to derive the Teukolsky master equations controlling massless scalar, neutrino, electromagnetic, gravitino, and gravitational field perturbations of the Kerr-de Sitter spacetime. Then the quantum entropy of a non-extreme Kerr-de Sitter black hole due to arbitrary spin fields is calculated by the improved thin-layer brick wall model. It is shown that the subleading order contribution to the entropy is dependent on the square of the spins of particles and that of the specific angular momentum of black holes as well as the cosmological constant. The logarithmic correction of the spins of particles to the entropy relies on the rotation of the black hole and the effect of the cosmological constant.Comment: 28 pages, two figures, Revtex4.0. Final revised version to appear in PR

    Star formation in the local Universe from the CALIFA sample: I. Calibrating the SFR using integral field spectroscopy data

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    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 <z< 0.03 using single-band and hybrid tracers. We aim to determine whether the extinction-corrected Hα luminosities provide a good measure of the SFR and to shed light on the origin of the discrepancies between tracers. Updated calibrations referred to Hα are provided. The well-defined selection criteria and large statistics allow us to carry out this analysis globally and split by properties, including stellar mass and morphological type. Methods. We derive integrated, extinction-corrected Hα fluxes from CALIFA, UV surface and asymptotic photometry from GALEX and integrated WISE 22 Όm and IRAS fluxes. Results. We find that the extinction-corrected Hα luminosity agrees with the hybrid updated SFR estimators based on either UV or Hα plus IR luminosity over the full range of SFRs (0.03-20 M yr). The coefficient that weights the amount of energy produced by newly-born stars that is reprocessed by dust on the hybrid tracers, a, shows a large dispersion. However, this coefficient does not became increasingly small at high attenuations, as expected if significant highly-obscured Hα emission were missed, i.e., after a Balmer decrement-based attenuation correction is applied. Lenticulars, early-type spirals, and type-2 AGN host galaxies show smaller coefficients because of the contribution of optical photons and AGN to dust heating. Conclusions. In the local Universe, the Hα luminosity derived from IFS observations can be used to measure SFR, at least in statistically-significant, optically-selected galaxy samples, once stellar continuum absorption and dust attenuation effects are accounted for. The analysis of the SFR calibrations by galaxies properties could potentially be used by other works to study the impact of different selection criteria in the SFR values derived, and to disentangle selection effects from other physically motivated differences, such as environmental or evolutionary effects.The CALIFA collaboration also thanks the CAHA staff for the dedication to this project. C.C.-T. thanks the support of the Spanish Ministerio de Educacion, Cultura y Deporte by means of the FPU fellowship program. The authors also thank the support from the Plan Nacional de Investigacion y Desarrollo funding programs, AYA2012-30717 and AyA2013-46724P, of Spanish Ministerio de Economia 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 Andalucia 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 Fundacao para a Ciencia 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 FCT-MEC (PIDDAC) and FEDER (COMPETE).Peer Reviewe

    The Pierre Auger Observatory III: Other Astrophysical Observations

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    Astrophysical observations of ultra-high-energy cosmic rays with the Pierre Auger ObservatoryComment: Contributions to the 32nd International Cosmic Ray Conference, Beijing, China, August 201

    Highlights from the Pierre Auger Observatory

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    The Pierre Auger Observatory is the world's largest cosmic ray observatory. Our current exposure reaches nearly 40,000 km2^2 str and provides us with an unprecedented quality data set. The performance and stability of the detectors and their enhancements are described. Data analyses have led to a number of major breakthroughs. Among these we discuss the energy spectrum and the searches for large-scale anisotropies. We present analyses of our Xmax_{max} data and show how it can be interpreted in terms of mass composition. We also describe some new analyses that extract mass sensitive parameters from the 100% duty cycle SD data. A coherent interpretation of all these recent results opens new directions. The consequences regarding the cosmic ray composition and the properties of UHECR sources are briefly discussed.Comment: 9 pages, 12 figures, talk given at the 33rd International Cosmic Ray Conference, Rio de Janeiro 201

    Hadron Energy Reconstruction for the ATLAS Calorimetry in the Framework of the Non-parametrical Method

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    This paper discusses hadron energy reconstruction for the ATLAS barrel prototype combined calorimeter (consisting of a lead-liquid argon electromagnetic part and an iron-scintillator hadronic part) in the framework of the non-parametrical method. The non-parametrical method utilizes only the known e/he/h ratios and the electron calibration constants and does not require the determination of any parameters by a minimization technique. Thus, this technique lends itself to an easy use in a first level trigger. The reconstructed mean values of the hadron energies are within ±1\pm 1% of the true values and the fractional energy resolution is [(58±3)/E+(2.5±0.3)[(58\pm3)% /\sqrt{E}+(2.5\pm0.3)%]\oplus (1.7\pm0.2)/E. The value of the e/he/h ratio obtained for the electromagnetic compartment of the combined calorimeter is 1.74±0.041.74\pm0.04 and agrees with the prediction that e/h>1.7e/h > 1.7 for this electromagnetic calorimeter. Results of a study of the longitudinal hadronic shower development are also presented. The data have been taken in the H8 beam line of the CERN SPS using pions of energies from 10 to 300 GeV.Comment: 33 pages, 13 figures, Will be published in NIM

    A search for point sources of EeV photons

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    Measurements of air showers made using the hybrid technique developed with the fluorescence and surface detectors of the Pierre Auger Observatory allow a sensitive search for point sources of EeV photons anywhere in the exposed sky. A multivariate analysis reduces the background of hadronic cosmic rays. The search is sensitive to a declination band from -85{\deg} to +20{\deg}, in an energy range from 10^17.3 eV to 10^18.5 eV. No photon point source has been detected. An upper limit on the photon flux has been derived for every direction. The mean value of the energy flux limit that results from this, assuming a photon spectral index of -2, is 0.06 eV cm^-2 s^-1, and no celestial direction exceeds 0.25 eV cm^-2 s^-1. These upper limits constrain scenarios in which EeV cosmic ray protons are emitted by non-transient sources in the Galaxy.Comment: 28 pages, 10 figures, accepted for publication in The Astrophysical Journa

    Reconstruction of inclined air showers detected with the Pierre Auger Observatory

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    We describe the method devised to reconstruct inclined cosmic-ray air showers with zenith angles greater than 60∘60^\circ detected with the surface array of the Pierre Auger Observatory. The measured signals at the ground level are fitted to muon density distributions predicted with atmospheric cascade models to obtain the relative shower size as an overall normalization parameter. The method is evaluated using simulated showers to test its performance. The energy of the cosmic rays is calibrated using a sub-sample of events reconstructed with both the fluorescence and surface array techniques. The reconstruction method described here provides the basis of complementary analyses including an independent measurement of the energy spectrum of ultra-high energy cosmic rays using very inclined events collected by the Pierre Auger Observatory.Comment: 27 pages, 19 figures, accepted for publication in Journal of Cosmology and Astroparticle Physics (JCAP
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