36 research outputs found

    The Baryon Oscillation Spectroscopic Survey of SDSS-III

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    The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the scale of baryon acoustic oscillations (BAO) in the clustering of matter over a larger volume than the combined efforts of all previous spectroscopic surveys of large scale structure. BOSS uses 1.5 million luminous galaxies as faint as i=19.9 over 10,000 square degrees to measure BAO to redshifts z<0.7. Observations of neutral hydrogen in the Lyman alpha forest in more than 150,000 quasar spectra (g<22) will constrain BAO over the redshift range 2.15<z<3.5. Early results from BOSS include the first detection of the large-scale three-dimensional clustering of the Lyman alpha forest and a strong detection from the Data Release 9 data set of the BAO in the clustering of massive galaxies at an effective redshift z = 0.57. We project that BOSS will yield measurements of the angular diameter distance D_A to an accuracy of 1.0% at redshifts z=0.3 and z=0.57 and measurements of H(z) to 1.8% and 1.7% at the same redshifts. Forecasts for Lyman alpha forest constraints predict a measurement of an overall dilation factor that scales the highly degenerate D_A(z) and H^{-1}(z) parameters to an accuracy of 1.9% at z~2.5 when the survey is complete. Here, we provide an overview of the selection of spectroscopic targets, planning of observations, and analysis of data and data quality of BOSS.Comment: 49 pages, 16 figures, accepted by A

    The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey

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    The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar spectra, along with the data presented in previous data releases. These spectra were obtained with the new BOSS spectrograph and were taken between 2009 December and 2011 July. In addition, the stellar parameters pipeline, which determines radial velocities, surface temperatures, surface gravities, and metallicities of stars, has been updated and refined with improvements in temperature estimates for stars with T_eff<5000 K and in metallicity estimates for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars presented in DR8, including stars from SDSS-I and II, as well as those observed as part of the SDSS-III Sloan Extension for Galactic Understanding and Exploration-2 (SEGUE-2). The astrometry error introduced in the DR8 imaging catalogs has been corrected in the DR9 data products. The next data release for SDSS-III will be in Summer 2013, which will present the first data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) along with another year of data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at http://www.sdss3.org/dr

    The Sloan Digital Sky Survey quasar catalog: tenth data release

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    We present the Data Release 10 Quasar (DR10Q) catalog from the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey III. The catalog includes all BOSS objects that were targeted as quasar candidates during the first 2.5 years of the survey and that are confirmed as quasars via visual inspection of the spectra, have luminosities M-i[z = 2] 2.15 (117 668) is similar to 5 times greater than the number of z > 2.15 quasars known prior to BOSS. Redshifts and FWHMs are provided for the strongest emission lines (C IV, C III, Mg II). The catalog identifies 16 461 broad absorption line quasars and gives their characteristics. For each object, the catalog presents five-band (u, g, r, i, z) CCD-based photometry with typical accuracy of 0.03 mag and information on the optical morphology and selection method. The catalog also contains X-ray, ultraviolet, near-infrared, and radio emission properties of the quasars, when available, from other large-area surveys. The calibrated digital spectra cover the wavelength region 3600-10 500 angstrom at a spectral resolution in the range 1300 < R < 2500; the spectra can be retrieved from the SDSS Catalog Archive Server. We also provide a supplemental list of an additional 2376 quasars that have been identified among the galaxy targets of the SDSS-III/BOSS

    Cosmological implications of baryon acoustic oscillation measurements

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    We derive constraints on cosmological parameters and tests of dark energy models from the combination of baryon acoustic oscillation (BAO) measurements with cosmic microwave background (CMB) data and a recent reanalysis of Type Ia supernova (SN) data. In particular, we take advantage of high-precision BAO measurements from galaxy clustering and the Lyman-α forest (LyaF) in the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). Treating the BAO scale as an uncalibrated standard ruler, BAO data alone yield a high confidence detection of dark energy; in combination with the CMB angular acoustic scale they further imply a nearly flat universe. Adding the CMB-calibrated physical scale of the sound horizon, the combination of BAO and SN data into an “inverse distance ladder” yields a measurement of H0 =67.3 ± 1.1 km s-1 Mpc-1, with 1.7% precision. This measurement assumes standard prerecombination physics but is insensitive to assumptions about dark energy or space curvature, so agreement with CMB-based estimates that assume a flat Λ CDM cosmology is an important corroboration of this minimal cosmological model. For constant dark energy (Λ), our BAO + SN + CMB combination yields matter density Ωm = 0.301 ± 0.008 and curvature Ωk = -0.003 ± 0.003. When we allow more general forms of evolving dark energy, the BAO + SN + CMB parameter constraints are always consistent with flat Λ CDM values at ≈1σ. While the overall χ2 of model fits is satisfactory, the LyaF BAO measurements are in moderate (2–2.5σ) tension with model predictions. Models with early dark energy that tracks the dominant energy component at high redshift remain consistent with our expansion history constraints, and they yield a higher H0 and lower matter clustering amplitude, improving agreement with some low redshift observations. Expansion history alone yields an upper limit on the summed mass of neutrino species, ∑mÎœ (95% confidence), improving to ∑mÎœ if we include the lensing signal in the Planck CMB power spectrum. In a flat Λ CDM model that allows extra relativistic species, our data combination yields Neff = 3.43 ± 0.26; while the LyaF BAO data prefer higher Neff when excluding galaxy BAO, the galaxy BAO alone favor Neff ≈ 3. When structure growth is extrapolated forward from the CMB to low redshift, standard dark energy models constrained by our data predict a level of matter clustering that is high compared to most, but not all, observational estimates

    The Baryon Oscillation Spectroscopic Survey of SDSS-III

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    The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the scale of baryon acoustic oscillations (BAO) in the clustering of matter over a larger volume than the combined efforts of all previous spectroscopic surveys of large-scale structure. BOSS uses 1.5 million luminous galaxies as faint as i = 19.9 over 10,000 deg(2) to measure BAO to redshifts z < 0.7. Observations of neutral hydrogen in the Ly alpha forest in more than 150,000 quasar spectra (g < 22) will constrain BAO over the redshift range 2.15 < z < 3.5. Early results from BOSS include the first detection of the large-scale three-dimensional clustering of the Ly alpha forest and a strong detection from the Data Release 9 data set of the BAO in the clustering of massive galaxies at an effective redshift z = 0.57. We project that BOSS will yield measurements of the angular diameter distance d(A) to an accuracy of 1.0% at redshifts z = 0.3 and z = 0.57 and measurements of H(z) to 1.8% and 1.7% at the same redshifts. Forecasts for Ly alpha forest constraints predict a measurement of an overall dilation factor that scales the highly degenerate D-A(z) and H-1(z) parameters to an accuracy of 1.9% at z similar to 2.5 when the survey is complete. Here, we provide an overview of the selection of spectroscopic targets, planning of observations, and analysis of data and data quality of BOSS

    Quasar-Lyman α forest cross-correlation from BOSS DR11: Baryon Acoustic Oscillations

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    We measure the large-scale cross-correlation of quasars with the Lyman alpha forest absorption, using over 164,000 quasars from Data Release 11 of the SDSS-III Baryon Oscillation Spectroscopic Survey. We extend the previous study of roughly 60,000 quasars from Data Release 9 to larger separations, allowing a measurement of the Baryonic Acoustic Oscillation (BAO) scale along the line of sight c/(H(z=2.36) rs)=9.0±0.3c/(H(z=2.36) ~ r_s) = 9.0 \pm 0.3 and across the line of sight DA(z=2.36)/ rs=10.8±0.4D_A(z=2.36) / ~ r_s = 10.8 \pm 0.4, consistent with CMB and other BAO data. Using the best fit value of the sound horizon from Planck data (rs=147.49Mpcr_s=147.49 Mpc), we can translate these results to a measurement of the Hubble parameter of H(z=2.36)=226±8km/s/MpcH(z=2.36) = 226 \pm 8 km/s / Mpc and of the angular diameter distance of DA(z=2.36)=1590±60MpcD_A(z=2.36) = 1590 \pm 60 Mpc. The measured cross-correlation function and an update of the code to fit the BAO scale (baofit) are made publicly available.Comment: 26 pages, 7 figures, version published by JCAP, with some extra comments suggested by the referee. Results unchanged from previous versio

    The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III

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    The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg2 of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg2 of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg2; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra. \ua9 2015. The American Astronomical Society

    Médecine générale et chirurgie ambulatoire (place de l'omnipraticien dans la prise en charge péri-opératoire de l'opéré)

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    MONTPELLIER-BU MĂ©decine (341722104) / SudocMONTPELLIER-BU MĂ©decine UPM (341722108) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

    Contribution des techniques d'anesthésie et de réanimation à la prévention et au traitement des pathologies douloureuses de l'appareil locomoteur

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    MONTPELLIER-BU MĂ©decine UPM (341722108) / SudocPARIS-BIUP (751062107) / SudocMONTPELLIER-BU MĂ©decine (341722104) / SudocSudocFranceF

    Le rÎle du médecin généraliste dans la prise en charge de l'algodystrophie ou syndrome douloureux régional complexe type 1

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    L'algodystrophie, ou syndrome douloureux complexe de type l, est une affection douloureuse chronique invalidante peu frĂ©quente mais Ă  laquelle le mĂ©decin gĂ©nĂ©raliste est confrontĂ©. Nous avons Ă©tudiĂ© les croyances et actions des mĂ©decins gĂ©nĂ©ralistes de la rĂ©gion Languedoc-Roussillon Ă  l'aide d'un questionnaire (22 questions) afin d'Ă©tudier le rĂŽle du mĂ©decin gĂ©nĂ©raliste dans la prise en charge de l algodystrophie en confrontant les rĂ©ponses aux donnĂ©es scientifiques actuelles. 268 mĂ©decins ont rĂ©pondu au questionnaire (taux de rĂ©ponse de 14 %) ce qui nous a permis de confirmer l'existence d'un tel rĂŽle (100 % des mĂ©decins interrogĂ©s pensent avoir un rĂŽle Ă  jouer et les donnĂ©es de la littĂ©rature le confirment) et de prĂ©ciser ce rĂŽle dans chacune des situations rencontrĂ©es : la prĂ©vention, le dĂ©pistage, le diagnostic, le traitement, le suivi et la recherche mĂ©dicale. Si le mĂ©decin gĂ©nĂ©raliste rencontre des difficultĂ©s dans cette prise en charge (80 % des mĂ©decins de notre Ă©tude), des recommandations thĂ©rapeutiques existent et lui permettent, par sa place dans le parcours de soin du patient, de contribuer par de nombreux moyens Ă  l'amĂ©lioration de la prise en charge de l'affection. Ces moyens doivent maintenant ĂȘtre diffusĂ©s (information aux mĂ©decins, aux patients et aux associations de patient), et dĂ©veloppĂ©s (outils d'Ă©valuation) afin de permettre au patient, Ă  son mĂ©decin gĂ©nĂ©raliste et aux nombreux intervenants concernĂ©s de travailler ensembleAlgodystrophy or Complex Regional Pain Syndrome is a painful, chronic, incapacitating and uncommon complaint which General Practitioners nevertheless come across. We have studied the perceptions and actions of General Practitioners throughout the Languedoc-Roussillon region with the help of a questionnaire (22 questions) in order to evaluate the role of General Practitioners in treating algodystrophy by comparing their answers the existing scientific data. 268 doctors filled in the questionnaire which enables us to confrrm the existence of such a role (100 % of the doctors who were questioned believe they play a role and this has been confrrmed by literature) and to clarify this role in different situations such as prevention, screening, diagnosis, treatment, follow up care and medical research. If General Practitioners fmd treating this pathology difficult (80 % of the doctors who answered our questionnaire do), therapeutic recom:rnendations exist and enable them, in different ways, through their position in the patients' care to contribute to a better treatment of this complaint. These recommendations must be spread (information to doctors, patients and patient organisations) and developed (evaluation tools) in order to enable the patient, his General Practitioner and others in the medical team to work togetherMONTPELLIER-BU MĂ©decine UPM (341722108) / SudocMONTPELLIER-BU MĂ©decine (341722104) / SudocSudocFranceF
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