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- ID:
- ivo://CDS.VizieR/J/A+A/640/A106
- Title:
- MUSE MATLAS-2019 spectral datacube
- Short Name:
- J/A+A/640/A106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The MATLAS deep imaging survey has uncovered a plethora of dwarf galaxies in the low density environment it has mapped. A fraction of them are unusually extended and have a low-surface brightness. Among these so-called ultra-diffuse galaxies, a few seem to host an excess of globular clusters. With the integral-field unit spectrograph MUSE we have observed one of these galaxies - MATLAS J15052031+0148447 (MATLAS-2019) - located towards the nearby group NGC 5846 and measured its systemic velocity,age, and metallicity, and that of its globular clusters candidates. For the stellar body of MATLAS-2019 we derive a metallicity of -1.33^+0.19^-_0.01_dex and an age of 11.2^+1.8^_-0.8_Gyr. For some of the individual GCs and the stacked GC population, we derive consistent ages and metallicities. From the 11 confirmed globular clusters and using a Markov Chain Monte Carlo approach we derived a dynamical mass-to-light ratio of 4.2^+8.6^-_3.4_M/L. This is at the lower end of the luminosity-mass scaling relation defined by the Local Group dwarf galaxies. Furthermore, we couldn't confirm nor reject the possibility of a rotational component of the GC system. If present, this would further modify the inferred mass. Follow-up observations of the globular cluster population and of the stellar body of the galaxy are needed to assess whether this galaxy is lacking dark matter like it was suggested for the pair of dwarf galaxies in the field of NGC 1052, or if this is a miss-interpretation arising from systematic uncertainties of the method commonly used for these systems and the large uncertainties of the individual globular cluster velocities.
- ID:
- ivo://CDS.VizieR/J/A+A/606/L11
- Title:
- MUSE observations SBS 0335-052E
- Short Name:
- J/A+A/606/L11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the discovery of ionised gas filaments in the circum-galactic halo of the extremely metal-poor compact starburst SBS 0335-052E in a 1.5h integration with the MUSE integral-field spectrograph. We detect these features in H{alpha} and [OIII] emission down to a limiting surface-brightness of 5x10^-19^erg/s/cm^2^/arcsec^2^. The filaments have projected diameters of 2.1kpc and extend more than 9kpc to the north and north-west from the main stellar body. We also detect extended nebular HeII {lambda}4686 emission that brightens towards the north-west at the rim of a starburst driven super-shell. We also present a velocity field of the ionised gas. The filaments appear to connect seamlessly in velocity space to the kinematical disturbances caused by the shell. Similar to high-z star-forming galaxies, the ionised gas in this galaxy is dispersion dominated. We argue that the filaments were created via feedback from the starburst and that these ionised structures in the halo may act as escape channels for Lyman continuum radiation in this gas-rich system.
- ID:
- ivo://CDS.VizieR/J/A+A/621/A107
- Title:
- MUSE-Wide Lyman alpha luminosity function 3<z<6
- Short Name:
- J/A+A/621/A107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the Lyman{alpha} emitter (LAE) luminosity function (LF) within the redshift range 2.9<=z<=6 from the first instalment of the blind integral field spectroscopic MUSE-Wide survey. This initial part of the survey probes a region of 22.2arcmin^2^ in the CANDELS/GOODS-S field (24 MUSE pointings with 1h integrations). The dataset provided us with 237 LAEs from which we construct the LAE LF in the luminosity range 42.2<=logL_Ly{alpha}_[erg/s]<=43.5 within a volume of 2.3x10^5^Mpc^3^. For the LF construction we utilise three different non-parametric estimators: the classical 1/V_max_ method, the C^-^ method, and an improved binned estimator for the differential LF. All three methods deliver consistent results, with the cumulative LAE LF being {Phi}(logL_Ly{alpha}_[erg/s]=43.5)~=3x10^-6^Mpc^-3^ and {Phi}(logL_Ly{alpha}_[erg/s]=42.2)~=2x10^-3^Mpc^-3^ towards the bright and faint end of our survey, respectively. By employing a non-parametric statistical test, and by comparing the full sample to subsamples in redshift bins, we find no supporting evidence for an evolving LAE LF over the probed redshift and luminosity range. Using a parametric maximum-likelihood technique we determine the best-fitting Schechter function parameters {alpha}=-1.84^+0.42^_-0.41_ and logL^*^[erg/s]=42.2^+0.22^_-0.16_ with the corresponding normalisation log{phi}^*^[Mpc^-3^]=-2.71. However, the dynamic range in Ly{alpha} luminosities probed by MUSE-Wide leads to a strong degeneracy between {alpha} and L^*^. Moreover, we find that a power-law parametrisation of the LF appears to be less consistent with the data compared to the Schechter function, even so when not excluding the X-Ray identified AGN from the sample. When correcting for completeness in the LAE LF determinations, we take into account that LAEs exhibit diffuse extended low surface brightness halos. We compare the resulting LF to one obtained by applying a correction assuming compact point-like emission. We find that the standard correction underestimates the LAE LF at the faint end of our survey by a factor of 2.5. Contrasting our results to the literature we find that at logL_Ly{alpha}_[erg/s]~<42.5 previous LAE LF determinations from narrow-band surveys appear to be affected by a similar bias.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A183
- Title:
- MUSE-Wide+MUSE-Deep EWs of Lyman{alpha} emitters
- Short Name:
- J/A+A/659/A183
- Date:
- 25 Mar 2022 09:08:03
- Publisher:
- CDS
- Description:
- The hydrogen Lyman{alpha} line is often the only measurable feature in optical spectra of high-redshift galaxies. Its shape and strength are influenced by radiative transfer processes and the properties of the underlying stellar population. High equivalent widths of several hundred {AA} are especially hard to explain by models and could point towards unusual stellar populations, for example with low metallicities, young stellar ages, and a top-heavy initial mass function. Other aspects influencing equivalent widths are the morphology of the galaxy and its gas properties. The aim of this study is to better understand the connection between the Lyman{alpha} rest-frame equivalent width (EW0) and spectral properties as well as ultraviolet (UV) continuum morphology by obtaining reliable EW0 histograms for a statistical sample of galaxies and by assessing the fraction of objects with large equivalent widths. We used integral field spectroscopy from the Multi Unit Spectroscopic Explorer (MUSE) combined with broad-band data from the Hubble Space Telescope (HST) to measure EW0 . We analysed the emission lines of 1920 Lyman{alpha} emitters (LAEs) detected in the full MUSE-Wide (one hour exposure time) and MUSE-Deep (ten hour exposure time) surveys and found UV continuum counterparts in archival HST data. We fitted the UV continuum photometric images using the Galfit software to gain morphological information on the rest-UV emission and fitted the spectra obtained from MUSE to determine the double peak fraction, asymmetry, full-width at half maximum, and flux of the Lyman{alpha} line. The two surveys show different histograms of Lyman{alpha} EW0 . In MUSE-Wide, 20% of objects have EW0>240{AA}, while this fraction is only 11% in MUSE-Deep and ~=16% for the full sample. This includes objects without HST continuum counterparts (one-third of our sample), for which we give lower limits for EW0. The object with the highest securely measured EW0 has EW0=589+/-193{AA} (the highest lower limit being EW0=4464{AA}). We investigate the connection between EW0 and Lyman{alpha} spectral or UV continuum morphological properties. The survey depth has to be taken into account when studying EW0 distributions. We find that in general, high EW0 objects can have a wide range of spectral and UV morphological properties, which might reflect that the underlying causes for high EW0 values are equally varied.
- ID:
- ivo://CDS.VizieR/J/A+A/624/A141
- Title:
- MUSE-Wide Survey DR1 catalog
- Short Name:
- J/A+A/624/A141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the MUSE-Wide survey, a blind, 3D spectroscopic survey in the CANDELS/GOODS-S and CANDELS/COSMOS regions. The final survey will cover 100x1arcmin^2^ MUSE fields. Each MUSE-Wide pointing has a depth of one hour and hence targets more extreme and more luminous objects over ten times the area of the MUSE-Deep fields (Bacon et al., 2017A&A...608A...1B). The legacy value of MUSE-Wide lies in providing "spectroscopy of everything" without photometric pre-selection. We describe the data reduction, post-processing and PSF characterization of the first 44 CANDELS/GOODS-S MUSE-Wide pointings released with this publication. Using a 3D matched filtering approach we detect 1602 emission line sources, including 479 Lyman-{alpha} (Lya) emitting galaxies with redshifts 2.9<~z<~6.3. We cross-matched the emission line sources to existing photometric catalogs, finding almost complete agreement in redshifts (photometric and spectroscopic) and stellar masses for our low redshift (z<1.5) emitters. At high redshift, we only find ~55% matches to photometric catalogs. We encounter a higher outlier rate and a systematic offset of {Delta}z~=0.2 when comparing our MUSE redshifts with photometric redshifts from the literature. Cross-matching the emission line sources with X-ray catalogs from the Chandra Deep Field South, we find 127 matches, mostly in agreement with the literature redshifts, including ten objects with no prior spectroscopic identification. Stacking X-ray images centered on our Lya emitters yields no signal; the Lya population is not dominated by even low luminosity AGN. Other cross-matches of our emission-line catalog to radio and submm data, yielded far lower numbers of matches, most of which already were covered by the X-ray catalog. A total of 9205 photometrically selected objects from the CANDELS survey lie in the MUSE-Wide footprint, of which we provide optimally extracted 1D spectra. We are able to determine the spectroscopic redshift of 98% of 772 photometrically selected galaxies brighter than 24th F775W magnitude. All the data in the first data release - datacubes, catalogs, extracted spectra, maps - are available on the website https://musewide.aip.de.
- ID:
- ivo://CDS.VizieR/J/A+A/606/A12
- Title:
- MUSE-Wide survey: 831 emission line galaxies
- Short Name:
- J/A+A/606/A12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a first instalment of the MUSE-Wide survey, covering an area of 22.2 arcmin^2^ (corresponding to ~20% of the final survey) in the CANDELS/Deep area of the Chandra Deep Field South. We use the MUSE integral field spectrograph at the ESO VLT to conduct a full-area spectroscopic mapping at a depth of 1h exposure time per 1-arcmin^2^ pointing. We searched for compact emission line objects using our newly developed LSDCat software based on a 3-D matched filtering approach, followed by interactive classification and redshift measurement of the sources. Our catalogue contains 831 distinct emission line galaxies with redshifts ranging from 0.04 to 6. Roughly one third (237) of the emission line sources are Lyman{alpha} emitting galaxies with 3<z<6, only four of which had previously measured spectroscopic redshifts. At lower redshifts 351 galaxies are detected primarily by their [OII] emission line (0.3<~z<~1.5), 189 by their [OIII] line (0.21<~z<~0.85), and 46 by their H{alpha} line (0.04<~z<~0.42). Comparing our spectroscopic redshifts to photometric redshift estimates from the literature, we find excellent agreement for z<1.5 with a median {Delta}z of only ~4x10^-4^ and an outlier rate of 6%, however a significant systematic offset of {Delta}z=0.26 and an outlier rate of 23% for Ly{alpha} emitters at z>3. Together with the catalogue we also release 1D PSF-weighted extracted spectra and small 3D datacubes centred on each of the 831 sources.
- ID:
- ivo://CDS.VizieR/J/ApJ/772/131
- Title:
- Musket Ball Cluster redshift catalog
- Short Name:
- J/ApJ/772/131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Merging galaxy clusters have become one of the most important probes of dark matter, providing evidence for dark matter over modified gravity and even constraints on the dark matter self-interaction cross-section. To properly constrain the dark matter cross-section it is necessary to understand the dynamics of the merger, as the inferred cross-section is a function of both the velocity of the collision and the observed time since collision. While the best understanding of merging system dynamics comes from N-body simulations, these are computationally intensive and often explore only a limited volume of the merger phase space allowed by observed parameter uncertainty. Simple analytic models exist but the assumptions of these methods invalidate their results near the collision time, plus error propagation of the highly correlated merger parameters is unfeasible. To address these weaknesses I develop a Monte Carlo method to discern the properties of dissociative mergers and propagate the uncertainty of the measured cluster parameters in an accurate and Bayesian manner. I introduce this method, verify it against an existing hydrodynamic N-body simulation, and apply it to two known dissociative mergers: 1ES 0657-558 (Bullet Cluster) and DLSCL J0916.2+2951 (Musket Ball Cluster).
- ID:
- ivo://CDS.VizieR/J/AJ/134/1103
- Title:
- MUSYC deep near-infrared imaging
- Short Name:
- J/AJ/134/1103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep near-infrared JHK imaging of four 10x10 fields. The observations were carried out as part of the Multiwavelength Survey by Yale-Chile (MUSYC) with ISPI on the CTIO 4m telescope. The typical point-source limiting depths are J~22.5, H~21.5, and K~21 (5{sigma}; Vega). The effective seeing in the final images is 1.0". We combine these data with MUSYC UBVRIz imaging to create K-selected catalogs that are unique for their uniform size, depth, filter coverage, and image quality.
- ID:
- ivo://CDS.VizieR/J/ApJS/189/270
- Title:
- MUSYC optical imaging in ECDF-S
- Short Name:
- J/ApJS/189/270
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep optical 18-medium-band photometry from the Subaru telescope over the ~30'x30' Extended Chandra Deep Field-South, as part of the Multiwavelength Survey by Yale-Chile (MUSYC). This field has a wealth of ground- and space-based ancillary data, and contains the GOODS-South field and the Hubble Ultra Deep Field. We combine the Subaru imaging with existing UBVRIzJHK and Spitzer IRAC images to create a uniform catalog. Detecting sources in the MUSYC "BVR" image we find ~40,000 galaxies with R_AB_<25.3, the median 5{sigma} limit of the 18 medium bands. Photometric redshifts are determined using the EAzY code and compared to ~2000 spectroscopic redshifts in this field. The medium-band filters provide very accurate redshifts for the (bright) subset of galaxies with spectroscopic redshifts, particularly at 0.1<z<1.2 and at z~>3.5. For 0.1<z<1.2, we find a 1{sigma} scatter in {DELTA}z/(1+z) of 0.007, similar to results obtained with a similar filter set in the COSMOS field. As a demonstration of the data quality, we show that the red sequence and blue cloud can be cleanly identified in rest-frame color-magnitude diagrams at 0.1<z<1.2. We find that ~20% of the red sequence galaxies show evidence of dust emission at longer rest-frame wavelengths. The reduced images, photometric catalog, and photometric redshifts are provided through the public MUSYC Web site (http://www.astro.yale.edu/MUSYC/).
