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  • 1
    In: The Astrophysical Journal, American Astronomical Society, Vol. 859, No. 1 ( 2018-05-23), p. 53-
    Type of Medium: Online Resource
    ISSN: 1538-4357
    Language: Unknown
    Publisher: American Astronomical Society
    Publication Date: 2018
    detail.hit.zdb_id: 2207648-7
    detail.hit.zdb_id: 1473835-1
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  • 2
    Online Resource
    Online Resource
    Oxford University Press (OUP) ; 2016
    In:  Monthly Notices of the Royal Astronomical Society Vol. 458, No. 3 ( 2016-05-21), p. 3210-3220
    In: Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP), Vol. 458, No. 3 ( 2016-05-21), p. 3210-3220
    Type of Medium: Online Resource
    ISSN: 0035-8711 , 1365-2966
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2016
    detail.hit.zdb_id: 2016084-7
    SSG: 16,12
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  • 3
    Online Resource
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    EDP Sciences ; 2020
    In:  Astronomy & Astrophysics Vol. 635 ( 2020-03), p. A194-
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 635 ( 2020-03), p. A194-
    Abstract: Context. One of the major science cases of the Multi Unit Spectroscopic Explorer (MUSE) integral field spectrograph is the detection of Lyman-alpha emitters at high redshifts. The on-going and planned deep fields observations will allow for one large sample of these sources. An efficient tool to perform blind detection of faint emitters in MUSE datacubes is a prerequisite of such an endeavor. Aims. Several line detection algorithms exist but their performance during the deepest MUSE exposures is hard to quantify, in particular with respect to their actual false detection rate, or purity. The aim of this work is to design and validate an algorithm that efficiently detects faint spatial-spectral emission signatures, while allowing for a stable false detection rate over the data cube and providing in the same time an automated and reliable estimation of the purity. Methods. The algorithm implements (i) a nuisance removal part based on a continuum subtraction combining a discrete cosine transform and an iterative principal component analysis, (ii) a detection part based on the local maxima of generalized likelihood ratio test statistics obtained for a set of spatial-spectral profiles of emission line emitters and (iii) a purity estimation part, where the proportion of true emission lines is estimated from the data itself: the distribution of the local maxima in the “noise only” configuration is estimated from that of the local minima. Results. Results on simulated data cubes providing ground truth show that the method reaches its aims in terms of purity and completeness. When applied to the deep 30 h exposure MUSE datacube in the Hubble Ultra Deep Field, the algorithms allows for the confirmed detection of 133 intermediate redshifts galaxies and 248 Ly α emitters, including 86 sources with no Hubble Space Telescope counterpart. Conclusions. The algorithm fulfills its aims in terms of detection power and reliability. It is consequently implemented as a Python package whose code and documentation are available on GitHub and readthedocs.
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    RVK:
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    Language: English
    Publisher: EDP Sciences
    Publication Date: 2020
    detail.hit.zdb_id: 1458466-9
    SSG: 16,12
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  • 4
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 608 ( 2017-12), p. A1-
    Abstract: We present the MUSE Hubble Ultra Deep Survey, a mosaic of nine MUSE fields covering 90% of the entire HUDF region with a 10-h deep exposure time, plus a deeper 31-h exposure in a single 1.15 arcmin 2 field. The improved observing strategy and advanced data reduction results in datacubes with sub-arcsecond spatial resolution (0.̋65 at 7000 Å) and accurate astrometry (0.̋07 rms). We compare the broadband photometric properties of the datacubes to HST photometry, finding a good agreement in zeropoint up to m AB = 28 but with an increasing scatter for faint objects. We have investigated the noise properties and developed an empirical way to account for the impact of the correlation introduced by the 3D drizzle interpolation. The achieved 3 σ emission line detection limit for a point source is 1.5 and 3.1 × 10 -19 erg s -1 cm -2 for the single ultra-deep datacube and the mosaic, respectively. We extracted 6288 sources using an optimal extraction scheme that takes the published HST source locations as prior. In parallel, we performed a blind search of emission line galaxies using an original method based on advanced test statistics and filter matching. The blind search results in 1251 emission line galaxy candidates in the mosaic and 306 in the ultradeep datacube, including 72 sources without HST counterparts ( m AB 〉 31). In addition 88 sources missed in the HST catalog but with clear HST counterparts were identified. This data set is the deepest spectroscopic survey ever performed. In just over 100 h of integration time, it provides nearly an order of magnitude more spectroscopic redshifts compared to the data that has been accumulated on the UDF over the past decade. The depth and high quality of these datacubes enables new and detailed studies of the physical properties of the galaxy population and their environments over a large redshift range.
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    RVK:
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    Language: English
    Publisher: EDP Sciences
    Publication Date: 2017
    detail.hit.zdb_id: 1458466-9
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  • 5
    In: Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP), Vol. 485, No. 2 ( 2019-05-11), p. 1961-1980
    Type of Medium: Online Resource
    ISSN: 0035-8711 , 1365-2966
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2019
    detail.hit.zdb_id: 2016084-7
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  • 6
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 638 ( 2020-06), p. A12-
    Abstract: Context. The Ly α emitter (LAE) fraction, X LAE , is a potentially powerful probe of the evolution of the intergalactic neutral hydrogen gas fraction. However, uncertainties in the measurement of X LAE are still under debate. Aims. Thanks to deep data obtained with the integral field spectrograph Multi Unit Spectroscopic Explorer (MUSE), we can measure the evolution of the LAE fraction homogeneously over a wide redshift range of z  ≈ 3–6 for UV-faint galaxies (down to UV magnitudes of M 1500  ≈ −17.75). This is a significantly fainter range than in former studies ( M 1500  ≤ −18.75) and it allows us to probe the bulk of the population of high-redshift star-forming galaxies. Methods. We constructed a UV-complete photometric-redshift sample following UV luminosity functions and measured the Ly α emission with MUSE using the latest (second) data release from the MUSE Hubble Ultra Deep Field Survey. Results. We derived the redshift evolution of X LAE for M 1500  ∈ [ − 21.75; −17.75] for the first time with a equivalent width range EW (Ly α ) ≥ 65 Å and found low values of X LAE  ≲ 30% at z  ≲ 6. The best-fit linear relation is X LAE = 0.07 +0.06 −0.03 z − 0.22 +0.12 −0.24 . For M 1500  ∈ [ − 20.25; −18.75] and EW (Ly α ) ≥ 25 Å, our X LAE values are consistent with those in the literature within 1 σ at z  ≲ 5, but our median values are systematically lower than reported values over the whole redshift range. In addition, we do not find a significant dependence of X LAE on M 1500 for EW (Ly α ) ≥ 50 Å at z  ≈ 3–4, in contrast with previous work. The differences in X LAE mainly arise from selection biases for Lyman Break Galaxies (LBGs) in the literature: UV-faint LBGs are more easily selected if they have strong Ly α emission, hence X LAE is biased towards higher values when those samples are used. Conclusions. Our results suggest either a lower increase of X LAE towards z  ≈ 6 than previously suggested, or even a turnover of X LAE at z  ≈ 5.5, which may be the signature of a late or patchy reionization process. We compared our results with predictions from a cosmological galaxy evolution model. We find that a model with a bursty star formation (SF) can reproduce our observed LAE fractions much better than models where SF is a smooth function of time.
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    RVK:
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    Language: English
    Publisher: EDP Sciences
    Publication Date: 2020
    detail.hit.zdb_id: 1458466-9
    SSG: 16,12
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  • 7
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 608 ( 2017-12), p. A8-
    Abstract: We report the detection of extended Ly α haloes around 145 individual star-forming galaxies at redshifts 3 ≤ z ≤ 6 in the Hubble Ultra Deep Field observed with the Multi-Unit Spectroscopic Explorer (MUSE) at ESO-VLT. Our sample consists of continuum-faint (− 15 ≥ M UV ≥ −22) Ly α emitters (LAEs). Using a 2D, two-component (continuum-like and halo) decomposition of Ly α emission assuming circular exponential distributions, we measure scale lengths and luminosities of Ly α haloes. We find that 80% of our objects having reliable Ly α halo measurements show Ly α emission that is significantly more extended than the UV continuum detected by HST (by a factor ≈4 to 〉 20). The median exponential scale length of the Ly α haloes in our sample is ≈4.5 kpc with a few haloes exceeding 10 kpc. By comparing the maximal detected extent of the Ly α emission with the predicted dark matter halo virial radii of simulated galaxies, we show that the detected Ly α emission of our selected sample of Ly α emitters probes a significant portion of the cold circum-galactic medium of these galaxies ( 〉 50% in average). This result therefore shows that there must be significant HI reservoirs in the circum-galactic medium and reinforces the idea that Ly α haloes are ubiquitous around high-redshift Ly α emitting galaxies. Our characterization of the Ly α haloes indicates that the majority of the Ly α flux comes from the halo (≈65%) and that their scale lengths seem to be linked to the UV properties of the galaxies (sizes and magnitudes). We do not observe a significant Ly α halo size evolution with redshift, although our sample for z 〉 5 is very small. We also explore the diversity of the Ly α line profiles in our sample and we find that the Ly α lines cover a large range of full width at half maximum (FWHM) from 118 to 512 km s -1 . While the FWHM does not seem to be correlated to the Ly α scale length, most compact Ly α haloes and those that are not detected with high significance tend to have narrower Ly α profiles ( 〈 350 km s -1 ). Finally, we investigate the origin of the extended Ly α emission but we conclude that our data do not allow us to disentangle the possible processes, i.e. scattering from star-forming regions, fluorescence, cooling radiation from cold gas accretion, and emission from satellite galaxies.
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    RVK:
    RVK:
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2017
    detail.hit.zdb_id: 1458466-9
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  • 8
    In: Open Forum Infectious Diseases, Oxford University Press (OUP), Vol. 8, No. 3 ( 2021-03-01)
    Abstract: We aimed to assess the prognostic value of repeated measurements of serum (1–3)-β-D-glucan (BDG), mannan-antigen (mannan-Ag), and antimannan antibodies (antimannan-Ab) for the occurrence of invasive candidiasis (IC) in a high-risk nonimmunocompromised population. Methods This was a preplanned ancillary analysis of the EMPIRICUS Randomized Clinical Trial, including nonimmunocompromised critically ill patients with intensive care unit–acquired sepsis, multiple Candida colonization, and multiple organ failure who were exposed to broad-spectrum antibacterial agents. BDG ( & gt;80 and & gt;250 pg/mL), mannan-Ag ( & gt;125 pg/mL), and antimannan-Ab ( & gt;10 AU) were collected repeatedly. We used cause-specific hazard models. Biomarkers were assessed at baseline in the whole cohort (cohort 1). Baseline covariates and/or repeated measurements and/or increased biomarkers were then studied in the subgroup of patients who were still alive at day 3 and free of IC (cohort 2). Results Two hundred thirty-four patients were included, and 215 were still alive and free of IC at day 3. IC developed in 27 patients (11.5%), and day 28 mortality was 29.1%. Finally, BDG  & gt;80 pg/mL at inclusion was associated with an increased risk of IC (CSHR[IC], 4.67; 95% CI, 1.61–13.5) but not death (CSHR[death] , 1.20; 95% CI, 0.71–2.02). Conclusions Among high-risk patients, a first measurement of BDG & gt;80 pg/mL was strongly associated with the occurrence of IC. Neither a cutoff of 250 pg/mL nor repeated measurements of fungal biomarkers seemed to be useful to predict the occurrence of IC. The cumulative risk of IC in the placebo group if BDG  & gt;80 pg/mL was 25.39%, which calls into question the efficacy of empirical therapy in this subgroup.
    Type of Medium: Online Resource
    ISSN: 2328-8957
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2021
    detail.hit.zdb_id: 2757767-3
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  • 9
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 670 ( 2023-02), p. A4-
    Abstract: We present the second data release of the MUSE Hubble Ultra-Deep Field surveys, which includes the deepest spectroscopic survey ever performed. The MUSE data, with their 3D content, amazing depth, wide spectral range, and excellent spatial and medium spectral resolution, are rich in information. Their location in the Hubble ultra-deep field area, which benefits from an exquisite collection of ancillary panchromatic information, is a major asset. This update of the first release incorporates a new 141-h adaptive-optics-assisted MUSE eXtremely Deep Field (MXDF; 1 arcmin diameter field of view) in addition to the reprocessed 10-h mosaic (3 × 3 arcmin 2 ) and the single 31-h deep field (1 × 1 arcmin 2 ). All three data sets were processed and analyzed homogeneously using advanced data reduction and analysis methods. The 3 σ point-source flux limit of an unresolved emission line reaches 3.1 × 10 −19 and 6.3 × 10 −20  erg s −1  cm −2 at 10- and 141-h depths, respectively. We have securely identified and measured the redshift of 2221 sources, an increase of 41% compared to the first release. With the exception of eight stars, the collected sample consists of 25 nearby galaxies ( z   〈  0.25), 677 [O  II ] emitters ( z = 0.25 − 1.5), 201 galaxies in the MUSE redshift desert range ( z  = 1.5 − 2.8), and 1308 Ly α emitters ( z  = 2.8 − 6.7). This represents an order of magnitude more redshifts than the collection of all spectroscopic redshifts obtained before MUSE in the Hubble ultra-deep field area (i.e., 2221 versus 292). At high redshift ( z   〉  3), the difference is even more striking, with a factor of 65 increase (1308 versus 20). We compared the measured redshifts against three published photometric redshift catalogs and find the photo-z accuracy to be lower than the constraints provided by photo-z fitting codes. Eighty percent of the galaxies in our final catalog have an HST counterpart. These galaxies are on average faint, with a median AB F 775 W magnitude of 25.7 and 28.7 for the [O  II ] and Ly α emitters, respectively. Fits of their spectral energy distribution show that these galaxies tend to be low-mass star-forming galaxies, with a median stellar mass of 6.2 × 10 8   M ⊙ and a median star-formation rate of 0.4  M ⊙ yr −1 . We measured the completeness of our catalog with respect to HST and found that, in the deepest 141-h area, 50% completeness is achieved for an AB magnitude of 27.6 and 28.7 ( F 775 W ) at z = 0.8 − 1.6 and z  = 3.2 − 4.5, respectively. Twenty percent of our catalog, or 424 galaxies, have no HST counterpart. The vast majority of these new sources are high equivalent-width z   〉  2.8 Ly α emitters that are detected by MUSE thanks to their bright and asymmetric broad Ly α line. We release advanced data products, specific software, and a web interface to select and download data sets.
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    RVK:
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    Language: English
    Publisher: EDP Sciences
    Publication Date: 2023
    detail.hit.zdb_id: 1458466-9
    SSG: 16,12
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  • 10
    In: The Astrophysical Journal, American Astronomical Society, Vol. 935, No. 2 ( 2022-08-01), p. 167-
    Abstract: The Astropy Project supports and fosters the development of open-source and openly developed Python packages that provide commonly needed functionality to the astronomical community. A key element of the Astropy Project is the core package astropy , which serves as the foundation for more specialized projects and packages. In this article, we summarize key features in the core package as of the recent major release, version 5.0, and provide major updates on the Project. We then discuss supporting a broader ecosystem of interoperable packages, including connections with several astronomical observatories and missions. We also revisit the future outlook of the Astropy Project and the current status of Learn Astropy. We conclude by raising and discussing the current and future challenges facing the Project.
    Type of Medium: Online Resource
    ISSN: 0004-637X , 1538-4357
    RVK:
    Language: Unknown
    Publisher: American Astronomical Society
    Publication Date: 2022
    detail.hit.zdb_id: 2207648-7
    detail.hit.zdb_id: 1473835-1
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