Browsing by Author "Wisotzki, Lutz"
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- ItemAn atlas of MUSE observations towards twelve massive lensing clusters(Les Ulis : EDP Sciences, 2021) Richard, Johan; Claeyssens, Adélaïde; Lagattuta, David; Guaita, Lucia; Bauer, Franz Erik; Pello, Roser; Carton, David; Bacon, Roland; Soucail, Geneviève; Lyon, Gonzalo Prieto; Kneib, Jean-Paul; Mahler, Guillaume; Clément, Benjamin; Mercier, Wilfried; Variu, Andrei; Tamone, Amélie; Ebeling, Harald; Schmidt, Kasper B.; Nanayakkara, Themiya; Maseda, Michael; Weilbacher, Peter M.; Bouché, Nicolas; Bouwens, Rychard J.; Wisotzki, Lutz; de la Vieuville, Geoffroy; Martinez, Johany; Patrício, VeraContext. Spectroscopic surveys of massive galaxy clusters reveal the properties of faint background galaxies thanks to the magnification provided by strong gravitational lensing. Aims. We present a systematic analysis of integral-field-spectroscopy observations of 12 massive clusters, conducted with the Multi Unit Spectroscopic Explorer (MUSE). All data were taken under very good seeing conditions (~0".6) in effective exposure times between two and 15 h per pointing, for a total of 125 h. Our observations cover a total solid angle of ~23 arcmin2 in the direction of clusters, many of which were previously studied by the MAssive Clusters Survey, Frontier Fields (FFs), Grism Lens-Amplified Survey from Space and Cluster Lensing And Supernova survey with Hubble programmes. The achieved emission line detection limit at 5? for a point source varies between (0.77-1.5) × 10-18 erg s-1 cm-2 at 7000 Å. Methods. We present our developed strategy to reduce these observational data, detect continuum sources and line emitters in the datacubes, and determine their redshifts. We constructed robust mass models for each cluster to further confirm our redshift measurements using strong-lensing constraints, and identified a total of 312 strongly lensed sources producing 939 multiple images. Results. The final redshift catalogues contain more than 3300 robust redshifts, of which 40% are for cluster members and ∼30% are for lensed Lyman-α emitters. Fourteen percent of all sources are line emitters that are not seen in the available HST images, even at the depth of the FFs (∼29 AB). We find that the magnification distribution of the lensed sources in the high-magnification regime (μ = 2–25) follows the theoretical expectation of N(z) ∝ μ−2. The quality of this dataset, number of lensed sources, and number of strong-lensing constraints enables detailed studies of the physical properties of both the lensing cluster and the background galaxies. The full data products from this work, including the datacubes, catalogues, extracted spectra, ancillary images, and mass models, are made available to the community.
- ItemDark Galaxy Candidates at Redshift ∼3.5 Detected with MUSE(London : Institute of Physics Publ., 2018) Anna Marino, Raffaella; Cantalupo, Sebastiano; Lilly, Simon J.; Gallego, Sofia G.; Straka, Lorrie A.; Borisova, Elena; Pezzulli, Gabriele; Bacon, Roland; Brinchmann, Jarle; Carollo, C. Marcella; Caruana, Joseph; Conseil, Simon; Contini, Thierry; Diener, Catrina; Finley, Hayley; Inami, Hanae; Leclercq, Floriane; Muzahid, Sowgat; Richard, Johan; Schaye, Joop; Wendt, Martin; Wisotzki, LutzRecent theoretical models suggest that the early phase of galaxy formation could involve an epoch when galaxies are gas rich but inefficient at forming stars: a "dark galaxy" phase. Here, we report the results of our Multi-Unit Spectroscopic Explorer (MUSE) survey for dark galaxies fluorescently illuminated by quasars at z > 3. Compared to previous studies which are based on deep narrowband (NB) imaging, our integral field survey provides a nearly uniform sensitivity coverage over a large volume in redshift space around the quasars as well as full spectral information at each location. Thanks to these unique features, we are able to build control samples at large redshift distances from the quasars using the same data taken under the same conditions. By comparing the rest-frame equivalent width (EW0) distributions of the Lyα sources detected in proximity to the quasars and in control samples, we detect a clear correlation between the locations of high-EW0 objects and the quasars. This correlation is not seen in other properties, such as Lyα luminosities or volume overdensities, suggesting the possible fluorescent nature of at least some of these objects. Among these, we find six sources without continuum counterparts and EW0 limits larger than 240 ∗ that are the best candidates for dark galaxies in our survey at z > 3.5. The volume densities and properties, including inferred gas masses and star formation efficiencies, of these dark galaxy candidates are similar to those of previously detected candidates at z ≈2.4 in NB surveys. Moreover, if the most distant of these are fluorescently illuminated by the quasar, our results also provide a lower limit of t =60 Myr on the quasar lifetime.
- ItemElevated ionizing photon production efficiency in faint high-equivalent-width Lyman-α emitters(Oxford : Oxford Univ. Press, 2020) Maseda, Michael V; Bacon, Roland; Lam, Daniel; Matthee, Jorryt; Brinchmann, Jarle; Schaye, Joop; Labbe, Ivo; Schmidt, Kasper B; Boogaard, Leindert; Bouwens, Rychard; Cantalupo, Sebastiano; Franx, Marijn; Hashimoto, Takuya; Inami, Hanae; Kusakabe, Haruka; Mahler, Guillaume; Nanayakkara, Themiya; Richard, Johan; Wisotzki, LutzWhile low-luminosity galaxies dominate number counts at all redshifts, their contribution to cosmic reionization is poorly understood due to a lack of knowledge of their physical properties. We isolate a sample of 35 z ≈ 4–5 continuum-faint Lyman-α emitters from deep VLT/MUSE spectroscopy and directly measure their H α emission using stacked Spitzer/IRAC Ch. 1 photometry. Based on Hubble Space Telescope imaging, we determine that the average UV continuum magnitude is fainter than −16 (≈ 0.01 L*), implying a median Lyman-α equivalent width of 259 Å. By combining the H α measurement with the UV magnitude, we determine the ionizing photon production efficiency, ξion, a first for such faint galaxies. The measurement of log10 (ξion [Hz erg−1]) = 26.28 (+−002840) is in excess of literature measurements of both continuum- and emission line-selected samples, implying a more efficient production of ionizing photons in these lower luminosity, Lyman-α-selected systems. We conclude that this elevated efficiency can be explained by stellar populations with metallicities between 4 × 10−4 and 0.008, with light-weighted ages less than 3 Myr.
- ItemHETDEX Public Source Catalog 1: 220 K Sources Including Over 50 K Lyα Emitters from an Untargeted Wide-area Spectroscopic Survey(London : Institute of Physics Publ., 2023) Mentuch Cooper, Erin; Gebhardt, Karl; Davis, Dustin; Farrow, Daniel J.; Liu, Chenxu; Zeimann, Gregory; Ciardullo, Robin; Feldmeier, John J.; Drory, Niv; Jeong, Donghui; Benda, Barbara; Bowman, William P.; Boylan-Kolchin, Michael; Chávez Ortiz, Óscar A.; Debski, Maya H.; Dentler, Mona; Fabricius, Maximilian; Farooq, Rameen; Finkelstein, Steven L.; Gawiser, Eric; Gronwall, Caryl; Hill, Gary J.; Hopp, Ulrich; House, Lindsay R.; Janowiecki, Steven; Khoraminezhad, Hasti; Kollatschny, Wolfram; Komatsu, Eiichiro; Landriau, Martin; Niemeyer, Maja Lujan; Lee, Hanshin; MacQueen, Phillip; Mawatari, Ken; McKay, Brianna; Ouchi, Masami; Poppe, Jennifer; Saito, Shun; Schneider, Donald P.; Snigula, Jan; Thomas, Benjamin P.; Tuttle, Sarah; Urrutia, Tanya; Weiss, Laurel; Wisotzki, Lutz; Zhang, YechiWe present the first publicly released catalog of sources obtained from the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). HETDEX is an integral field spectroscopic survey designed to measure the Hubble expansion parameter and angular diameter distance at 1.88 < z < 3.52 by using the spatial distribution of more than a million Lyα-emitting galaxies over a total target area of 540 deg2. The catalog comes from contiguous fiber spectra coverage of 25 deg2 of sky from 2017 January through 2020 June, where object detection is performed through two complementary detection methods: one designed to search for line emission and the other a search for continuum emission. The HETDEX public release catalog is dominated by emission-line galaxies and includes 51,863 Lyα-emitting galaxy (LAE) identifications and 123,891 [O ii]-emitting galaxies at z < 0.5. Also included in the catalog are 37,916 stars, 5274 low-redshift (z < 0.5) galaxies without emission lines, and 4976 active galactic nuclei. The catalog provides sky coordinates, redshifts, line identifications, classification information, line fluxes, [O ii] and Lyα line luminosities where applicable, and spectra for all identified sources processed by the HETDEX detection pipeline. Extensive testing demonstrates that HETDEX redshifts agree to within Δz < 0.02, 96.1% of the time to those in external spectroscopic catalogs. We measure the photometric counterpart fraction in deep ancillary Hyper Suprime-Cam imaging and find that only 55.5% of the LAE sample has an r-band continuum counterpart down to a limiting magnitude of r ∼ 26.2 mag (AB) indicating that an LAE search of similar sensitivity to HETDEX with photometric preselection would miss nearly half of the HETDEX LAE catalog sample. Data access and details about the catalog can be found online at http://hetdex.org/. A copy of the catalogs presented in this work (Version 3.2) is available to download at Zenodo doi:10.5281/zenodo.7448504.
- ItemThe MUSE Extremely Deep Field: The cosmic web in emission at high redshift(Les Ulis : EDP Sciences, 2021) Bacon, Roland; Mary, David; Garel, Thibault; Blaizot, Jeremy; Maseda, Michael; Schaye, Joop; Wisotzki, Lutz; Conseil, Simon; Brinchmann, Jarle; Leclercq, Floriane; Abril-Melgarejo, Valentina; Boogaard, Leindert; Bouché, Nicolas; Contini, Thierry; Feltre, Anna; Guiderdoni, Bruno; Herenz, Christian; Kollatschny, Wolfram; Kusakabe, Haruka; Matthee, Jorryt; Michel-Dansac, Léo; Nanayakkara, Themiya; Richard, Johan; Roth, Martin; Schmidt, Kasper B.; Steinmetz, Matthias; Tresse, Laurence; Urrutia, Tanya; Verhamme, Anne; Weilbacher, Peter M.; Zabl, Johannes; Zoutendijk, Sebastiaan L.We report the discovery of diffuse extended Lyα emission from redshift 3.1 to 4.5, tracing cosmic web filaments on scales of 2.5-4 cMpc. These structures have been observed in overdensities of Lyα emitters in the MUSE Extremely Deep Field, a 140 h deep MUSE observation located in the Hubble Ultra-Deep Field. Among the 22 overdense regions identified, five are likely to harbor very extended Lyα emission at high significance with an average surface brightness of 5 × 10-20 erg s-1 cm-2 arcsec-2. Remarkably, 70% of the total Lyα luminosity from these filaments comes from beyond the circumgalactic medium of any identified Lyα emitter. Fluorescent Lyα emission powered by the cosmic UV background can only account for less than 34% of this emission at z ≈ 3 and for not more than 10% at higher redshift. We find that the bulk of this diffuse emission can be reproduced by the unresolved Lyα emission of a large population of ultra low-luminosity Lyα emitters (< 1040 erg s-1), provided that the faint end of the Lyα luminosity function is steep (α ⪅ -1.8), it extends down to luminosities lower than 1038 - 1037 erg s-1, and the clustering of these Lyα emitters is significant (filling factor < 1/6). If these Lyα emitters are powered by star formation, then this implies their luminosity function needs to extend down to star formation rates < 10-4M yr-1. These observations provide the first detection of the cosmic web in Lyα emission in typical filamentary environments and the first observational clue indicating the existence of a large population of ultra low-luminosity Lyα emitters at high redshift. © R. Bacon et al. 2021.
- ItemThe MUSE Hubble Ultra Deep Field surveys: Data release II(Les Ulis : EDP Sciences, 2023) Bacon, Roland; Brinchmann, Jarle; Conseil, Simon; Maseda, Michael; Nanayakkara, Themiya; Wendt, Martin; Bacher, Raphael; Mary, David; Weilbacher, Peter M.; Krajnović, Davor; Boogaard, Leindert; Bouché, Nicolas; Contini, Thierry; Epinat, Benoît; Feltre, Anna; Guo, Yucheng; Herenz, Christian; Kollatschny, Wolfram; Kusakabe, Haruka; Leclercq, Floriane; Michel-Dansac, Léo; Pello, Roser; Richard, Johan; Roth, Martin; Salvignol, Gregory; Schaye, Joop; Steinmetz, Matthias; Tresse, Laurence; Urrutia, Tanya; Verhamme, Anne; Vitte, Eloise; Wisotzki, Lutz; Zoutendijk, Sebastiaan L.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 arcmin2) and the single 31-h deep field (1 × 1 arcmin2). All three data sets were processed and analyzed homogeneously using advanced data reduction and analysis methods. The 3σ 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 Lyα 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 F775W magnitude of 25.7 and 28.7 for the [O II] and Lyα 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 × 108 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 (F775W) 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 Lyα emitters that are detected by MUSE thanks to their bright and asymmetric broad Lyα line. We release advanced data products, specific software, and a web interface to select and download data sets.