- ID:
- ivo://CDS.VizieR/J/ApJ/843/31
- Title:
- MUSCLES Treasury Survey. IV. M dwarf UV fluxes
- Short Name:
- J/ApJ/843/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Characterizing the UV spectral energy distribution (SED) of an exoplanet host star is critically important for assessing its planet's potential habitability, particularly for M dwarfs, as they are prime targets for current and near-term exoplanet characterization efforts and atmospheric models predict that their UV radiation can produce photochemistry on habitable zone planets different from that on Earth. To derive ground-based proxies for UV emission for use when Hubble Space Telescope (HST) observations are unavailable, we have assembled a sample of 15 early to mid-M dwarfs observed by HST and compared their nonsimultaneous UV and optical spectra. We find that the equivalent width of the chromospheric Ca II K line at 3933{AA}, when corrected for spectral type, can be used to estimate the stellar surface flux in ultraviolet emission lines, including HI Ly{alpha}. In addition, we address another potential driver of habitability: energetic particle fluxes associated with flares. We present a new technique for estimating soft X-ray and >10MeV proton flux during far-UV emission line flares (Si IV and He II) by assuming solar-like energy partitions. We analyze several flares from the M4 dwarf GJ 876 observed with HST and Chandra as part of the MUSCLES Treasury Survey and find that habitable zone planets orbiting GJ 876 are impacted by large Carrington-like flares with peak soft X-ray fluxes >=10^-3^W/m^2^ and possible proton fluxes ~10^2^-10^3^pfu, approximately four orders of magnitude more frequently than modern-day Earth.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/473/663
- Title:
- MUSE and HFFs Photometry of A2744
- Short Name:
- J/MNRAS/473/663
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of Multi Unit Spectroscopic Explorer (MUSE) observations obtained on the massive Frontier Fields (FFs) cluster A2744. This new data set covers the entire multiply imaged region around the cluster core. The combined catalogue consists of 514 spectroscopic redshifts (with 414 new identifications). We use this redshift information to perform a strong-lensing analysis revising multiple images previously found in the deep FF images, and add three new MUSE-detected multiply imaged systems with no obvious Hubble Space Telescope counterpart. The combined strong-lensing constraints include a total of 60 systems producing 188 images altogether, out of which 29 systems and 83 images are spectroscopically confirmed, making A2744 one of the most well-constrained clusters to date. Thanks to the large amount of spectroscopic redshifts, we model the influence of substructures at larger radii, using a parametrization including two cluster-scale components in the cluster core and several group scale in the outskirts. The resulting model accurately reproduces all the spectroscopic multiple systems, reaching an rms of 0.67-arcsec in the image plane. The large number of MUSE spectroscopic redshifts gives us a robust model, which we estimate reduces the systematic uncertainty on the 2D mass distribution by up to ~2.5 times the statistical uncertainty in the cluster core. In addition, from a combination of the parametrization and the set of constraints, we estimate the relative systematic uncertainty to be up to 9 per cent at 200kpc.
- ID:
- ivo://CDS.VizieR/J/A+A/654/A80
- Title:
- MUSE Catalog of UV emission line measurement
- Short Name:
- J/A+A/654/A80
- Date:
- 02 Feb 2022 10:08:10
- Publisher:
- CDS
- Description:
- Rest-frame ultraviolet (UV) emission lines probe electron densities, gas-phase abundances, metallicities, and ionization parameters of the emitting star-forming galaxies and their environments. The strongest main UV emission line, Ly{alpha}, has been instrumental in advancing the general knowledge of galaxy formation in the early universe. However, observing Ly{alpha} emission becomes increasingly challenging at z>~6 when the neutral hydrogen fraction of the circumgalactic and intergalactic media increases. Secondary weaker UV emission lines provide important alternative methods for studying galaxy properties at high redshift. We present a large sample of rest-frame UV emission line sources at intermediate redshift for calibrating and exploring the connection between secondary UV lines and the emitting galaxies' physical properties and their Ly{alpha} emission. The sample of 2052 emission line sources with 1.5<z<6.4 was collected from integral field data from the MUSE-Wide and MUSE-Deep surveys taken as part of Guaranteed Time Observations. The objects were selected through untargeted source detection (i.e., no preselection of sources as in dedicated spectroscopic campaigns) in the three-dimensional MUSE data cubes. We searched optimally extracted one-dimensional spectra of the full sample for UV emission features via emission line template matching, resulting in a sample of more than 100 rest-frame UV emission line detections. We show that the detection efficiency of (non-Ly{alpha}) UV emission lines increases with survey depth, and that the emission line strength of HeII {lambda}1640AA, [OIII] {lambda}1661 + OIII] {lambda}1666, and [SiIII] {lambda}1883 + SiIII] {lambda}1892 correlate with the strength of [CIII] {lambda}1907 + CIII] {lambda}1909. The rest-frame equivalent width (EW0 ) of [CIII] {lambda}1907+CIII] {lambda}1909 is found to be roughly 0.22+/-0.18 of EW0 (Ly{alpha}). We measured the velocity offsets of resonant emission lines with respect to systemic tracers. For CIV {lambda}1548 + CIV {lambda}1551 we find that {DELTA}v_CIV_<~250km/s, whereas {nu}v_Ly{alpha}_ falls in the range of 250-500km/s which is in agreement with previous results from the literature. The electron density ne measured from [SiIII] {lambda}1883 + SiIII] {lambda}1892 and [CIII] {lambda}1907 + CIII] {lambda}1909 line flux ratios is generally <10^5^cm^-3^ and the gas-phase abundance is below solar at 12+log10(O/H)~=8. Lastly, we used "PhotoIonization Model Probability Density Functions" to infer physical parameters of the full sample and individual systems based on photoionization model parameter grids and observational constraints from our UV emission line searches. This reveals that the UV line emitters generally have ionization parameter log10(U) ~= -2.5 and metal mass fractions that scatter around Z~=10-2, that is Z~=0.66Z_{sun}_. Value-added catalogs of the full sample of MUSE objects studied in this work (this catalog) and a collection of UV line emitters from the literature are provided with this paper.
1664. MUSE datacube of He 2-10
- ID:
- ivo://CDS.VizieR/J/A+A/604/A101
- Title:
- MUSE datacube of He 2-10
- Short Name:
- J/A+A/604/A101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the physical and dynamical properties of the ionized gas in the prototypical HII galaxy Henize 2-10 using MUSE integral field spectroscopy. The large-scale dynamics are dominated by extended outflowing bubbles that are probably the result of massive gas ejection from the central star forming regions. We derived a mass outflow rate dM_out_/dt~0.30M_{sun}_/yr, corresponding to mass loading factor {eta}~0.4, in the range of similar measurements in local LIRGs. Such a massive outflow has a total kinetic energy that is sustainable by the stellar winds and supernova remnants expected in the galaxy. We studied the dust extinction, electron density, and ionization conditions all across the galaxy with a classical emission line diagnostic, confirming the extreme nature of the highly star forming knots in the core of the galaxy, which show high density and high ionization parameters. We measured the gas-phase metallicity in the galaxy, taking the strong variation of the ionization parameter into account, and found that the external parts of the galaxy have abundances as low as 12+log(O/H)~8.3, while the central star forming knots are highly enriched with super solar metallicity. We found no sign of AGN ionization in the galaxy, despite the recent claim of the presence of a supermassive active black hole in the core of He 2-10. We therefore reanalyzed the X-ray data that were used to propose the presence of the AGN, but we concluded that the observed X-ray emission can be better explained with sources of a different nature, such as a supernova remnant.
- ID:
- ivo://CDS.VizieR/J/A+A/644/A15
- Title:
- MUSE data for MR 2251-178 and PG 1126-041
- Short Name:
- J/A+A/644/A15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use MUSE adaptive optics (AO) data in Narrow Field Mode to study the properties of the ionised gas in MR 2251-178 and PG 1126-041, two nearby (z~0.06) bright quasars hosting sub-pc scale Ultra Fast Outflows (UFOs) detected in the X-ray band. We decompose the optical emission from diffuse gas into a low- and a high-velocity components. The former is characterised by a clean, regular velocity field and a low (~80 km/s) velocity dispersion. It traces regularly rotating gas in PG 1126-041, while in MR 2251-178 it is possibly associated to tidal debris from a recent merger or flyby. The other component is found to be extended up to a few kpc from the nuclei, and shows a high (~800km/s) velocity dispersion and a blue-shifted mean velocity, as expected from AGN-driven outflows. We estimate mass outflow rates up to a few Mo/yr and kinetic efficiencies between 0.1-0.4 per cent, in line with those of galaxies hosting AGNs of similar luminosity. The momentum rates of these ionised outflows are comparable to those measured for the UFOs at sub-pc scales, consistent with a momentum-driven wind propagation. Pure energy-driven winds are excluded unless about 100x additional momentum is locked in massive molecular winds. By comparing the outflow properties of our sources with those of a small sample of well-studied QSOs hosting UFOs from the literature, we find that winds seem to systematically lie either in a momentum-driven or in an energy-driven regime, indicating that these two theoretical models bracket very well the physics of AGN-driven winds.
1666. MUSE 3D view of HDF-S
- ID:
- ivo://CDS.VizieR/J/A+A/575/A75
- Title:
- MUSE 3D view of HDF-S
- Short Name:
- J/A+A/575/A75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We observed Hubble Deep Field South with the new panoramic integral-field spectrograph MUSE that we built and have just commissioned at the VLT. The data cube resulting from 27h of integration covers one arcmin^2^ field of view at an unprecedented depth with a 1{sigma} emission-line surface brightness limit of 1x10^-19^erg/s/cm2/arcsec2, and contains ~90000 spectra. We present the combined and calibrated data cube, and we performed a first-pass analysis of the sources detected in the Hubble Deep Field South imaging. We measured the redshifts of 189 sources up to a magnitude I_814_=29.5, increasing the number of known spectroscopic redshifts in this field by more than an order of magnitude. We also discovered 26 Ly{alpha} emitting galaxies that are not detected in the HST WFPC2 deep broad-band images. The intermediate spectral resolution of 2.3{AA} allows us to separate resolved asymmetric Ly{alpha} emitters, [OII]3727 emitters, and [CIII]1908 emitters, and the broad instantaneous wavelength range of 4500{AA} helps to identify single emission lines, such as [OIII]5007, H{beta}, and H{alpha}, over a very wide redshift range. We also show how the three-dimensional information of MUSE helps to resolve sources that are confused at ground-based image quality. Overall, secure identifications are provided for 83% of the 227 emission line sources detected in the MUSE data cube and for 32% of the 586 sources identified in the HST catalogue. The overall redshift distribution is fairly flat to z=6.3, with a reduction between z=1.5 to 2.9, in the well-known redshift desert. The field of view of MUSE also allowed us to detect 17 groups within the field. We checked that the number counts of [OII]3727 and Ly{alpha} emitters are roughly consistent with predictions from the literature. Using two examples, we demonstrate that MUSE is able to provide exquisite spatially resolved spectroscopic information on the intermediate-redshift galaxies present in the field. This unique data set can be used for a wide range of follow-up studies. We release the data cube, the associated products, and the source catalogue with redshifts, spectra, and emission-line fluxes.
- ID:
- ivo://CDS.VizieR/J/A+A/629/A100
- Title:
- MUSE library of stellar spectra
- Short Name:
- J/A+A/629/A100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Empirical stellar spectral libraries have applications in both extragalactic and stellar studies, and they confer an advantage over theoretical libraries because they naturally include all relevant chemical species and physical processes. In recent years we have seen a stream of new sets of high-quality spectra, but increasing the spectral resolution and widening the wavelength coverage means resorting to multi-order echelle spectrographs. Assembling the spectra from many pieces results in lower fidelity of their shapes. We aim to offer the community a library of high-signal-to-noise spectra with reliable continuum shapes. Furthermore, the use of an integral field unit (IFU) alleviates the issue of slit losses. Our library was built with the MUSE (Multi-Unit Spectroscopic Explorer) IFU instrument. We obtained spectra over nearly the entire visual band ({lambda}~4800-9300{AA}). We assembled a library of 35 high-quality MUSE spectra for a subset of the stars from the X-shooter Spectral Library. We verified the continuum shape of these spectra with synthetic broadband colors derived from the spectra. We also report some spectral indices from the Lick system, derived from the new observations. We offer a high-fidelity set of stellar spectra covering the Hertzsprung-Russell diagram. These can be used for both extragalactic and stellar studies and demonstrate that the IFUs are excellent tools for building reliable spectral libraries.
- 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/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.
