- ID:
- ivo://CDS.VizieR/J/MNRAS/490/243
- Title:
- ELAIS N1 field uGMRT 400MHz source catalog
- Short Name:
- J/MNRAS/490/243
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Understanding the low-frequency radio sky in depth is necessary to subtract foregrounds in order to detect the redshifted 21 cm signal of neutral hydrogen from the cosmic dawn, the epoch of reionization and the post-reionization era. In this second paper of the series, we present the upgraded Giant Metrewave Radio Telescope (uGMRT) observation of the ELAIS N1 field made at 300-500MHz. The image covers an area of ~1.8deg^2^ and has a central background rms noise of ~15uJy/beam. We present a radio source catalogue containing 2528 sources (with flux densities >100uJy) and normalized source counts derived from that. A detailed comparison of detected sources with previous radio observations is shown. We discuss flux-scale accuracy, positional offsets, spectral index distribution and correction factors in source counts. The normalized source counts are in agreement with previous observations of the same field, as well as model source counts from the Square Kilometre Array Design Study simulation. It shows a flattening below ~1mJy that corresponds to a rise in populations of star-forming galaxies and radio-quiet active galactic nuclei. For the first time, we estimate the spectral characteristics of the angular power spectrum or multi-frequency angular power spectrum of diffuse Galactic synchrotron emission over a wide frequency bandwidth of 300-500MHz from radio interferometric observations. This work demonstrates the improved capabilities of the uGMRT.
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Search Results
- ID:
- ivo://lam.cesam.aspic/el_cosmos_dr1/q/cone
- Title:
- EL COSMOS DR1 catalogue
- Short Name:
- ELCOSMOS1 SCS
- Date:
- 28 Apr 2022 21:55:18
- Publisher:
- The CeSAM VO team
- Description:
- Modeled magnitudes and emission line fluxes of COSMOS2015 sources
- ID:
- ivo://lam.cesam.aspic/el_cosmos_dr1/q/ssa
- Title:
- EL COSMOS DR1 spectra
- Short Name:
- ELCOSMOS1 SSAP
- Date:
- 28 Apr 2022 21:55:18
- Publisher:
- The CeSAM VO team
- Description:
- Synthetic spectra of COSMOS2015 sources
- ID:
- ivo://CDS.VizieR/J/AJ/135/1580
- Title:
- Element abundances in ten red giants of Car dSph
- Short Name:
- J/AJ/135/1580
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained high-resolution spectroscopy of ten red giants in the Carina dwarf spheroidal (dSph) galaxy with the ultraviolet and visual echelle spectrograph at the European Southern Observatory Very Large Telescope in order to study the detailed chemical evolution of this Galactic satellite. Here we present the abundances of O, Na, Mg, Si, Ca, Ti, and Fe.
- ID:
- ivo://CDS.VizieR/J/AJ/159/46
- Title:
- Elemental abundances of 416 stars in 5 dSphs of M31
- Short Name:
- J/AJ/159/46
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep spectroscopy from Keck/DEIMOS (DEep Imaging Multi-Object Spectrograph) of Andromeda I, III, V, VII, and X, all of which are dwarf spheroidal satellites (dSphs) of M31. The sample includes 256 spectroscopic members across all five dSphs. We confirm previous measurements of the velocity dispersions and dynamical masses, and we provide upper limits on bulk rotation. Our measurements confirm that M31 satellites obey the same relation between stellar mass and stellar metallicity as Milky Way (MW) satellites and other dwarf galaxies in the Local Group. The metallicity distributions show trends with stellar mass that are similar to those of MW satellites, including evidence in massive satellites for external influence, like pre-enrichment or gas accretion. We present the first measurements of individual element ratios, like [Si/Fe], in the M31 system, as well as measurements of the average [{alpha}/Fe] ratio. The trends of [{alpha}/Fe] with [Fe/H] also follow the same galaxy mass-dependent patterns as MW satellites. Less massive galaxies have more steeply declining slopes of [{alpha}/Fe] that begin at lower [Fe/H]. Finally, we compare the chemical evolution of M31 satellites to M31's Giant Stellar Stream and smooth halo. The properties of the M31 system support the theoretical prediction that the inner halo is composed primarily of massive galaxies that were accreted early. As a result, the inner halo exhibits higher [Fe/H] and [{alpha}/Fe] than surviving satellite galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/599/A83
- Title:
- ELG and AGN in WINGS clusters
- Short Name:
- J/A+A/599/A83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of the emission line galaxies members of 46 low-redshift (0.04<z<0.07) clusters observed by WINGS (WIde-field Nearby Galaxy cluster Survey; Fasano et al., 2006A&A...445..805F). Emission line galaxies were identified following criteria that are meant to minimize biases against non-star-forming galaxies and classified employing diagnostic diagrams. We examined the emission line properties and frequencies of star-forming galaxies, transition objects, and active galactic nuclei (AGNs: LINERs and Seyferts), unclassified galaxies with emission lines, and quiescent galaxies with no detectable line emission. A deficit of emission line galaxies in the cluster environment is indicated by both a lower frequency, and a systematically lower Balmer emission line equivalent width and luminosity with respect to control samples; this implies a lower amount of ionized gas per unit mass and a lower star formation rate if the source is classified as Hii region. A sizable population of transition objects and of low-luminosity LINERs (~10-20% of all emission line galaxies) are detected among WINGS cluster galaxies. These sources are a factor of 1.5 more frequent, or at least as frequent, as in control samples with respect to Hii sources. Transition objects and LINERs in clusters are most affected in terms of line equivalent width by the environment and appear predominantly consistent with so-called retired galaxies. Shock heating can be a possible gas excitation mechanism that is able to account for observed line ratios. Specific to the cluster environment, we suggest interaction between atomic and molecular gas and the intracluster medium as a possible physical cause of line-emitting shocks.
- ID:
- ivo://CDS.VizieR/J/ApJ/693/617
- Title:
- Ellipticities of cluster early-type galaxies
- Short Name:
- J/ApJ/693/617
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled a sample of early-type cluster galaxies from 0<z<1.3 and measured the evolution of their ellipticity distributions. Our sample contains 487 galaxies in 17 z>0.3 clusters with high-quality space-based imaging and a comparable sample of 210 galaxies in 10 clusters at z<0.05. We select early-type galaxies (elliptical and S0 galaxies) that fall within the cluster R_200_, and which lie on the red-sequence in the magnitude range -19.3>M_B_>-21, after correcting for luminosity evolution as measured by the fundamental plane.
- ID:
- ivo://CDS.VizieR/J/MNRAS/365/454
- Title:
- Emission line analysis of HII galaxies
- Short Name:
- J/MNRAS/365/454
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a statistical study of a very large sample of HII galaxies taken from the literature. We focus on the differences in several properties between galaxies that show the auroral line [OIII]{lambda}4363 and those that do not present this feature in their spectra.
- ID:
- ivo://CDS.VizieR/J/ApJS/192/5
- Title:
- Emission-line galaxies from HETDEX pilot survey
- Short Name:
- J/ApJS/192/5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of emission-line galaxies selected solely by their emission-line fluxes using a wide-field integral field spectrograph. This work is partially motivated as a pilot survey for the upcoming Hobby-Eberly Telescope Dark Energy Experiment. We describe the observations, reductions, detections, redshift classifications, line fluxes, and counterpart information for 397 emission-line galaxies detected over 169arcmin^2^ with a 3500-5800{AA} bandpass under 5{AA} full-width-half-maximum (FWHM) spectral resolution. The survey's best sensitivity for unresolved objects under photometric conditions is between 4 and 20x10^-17^erg/s/cm^2^ depending on the wavelength, and Ly{alpha} luminosities between 3x10^42^ and 6x10^42^erg/s are detectable. This survey method complements narrowband and color-selection techniques in the search of high-redshift galaxies with its different selection properties and large volume probed. The four survey fields within the COSMOS, GOODS-N, MUNICS, and XMM-LSS areas are rich with existing, complementary data. We find 105 galaxies via their high-redshift Ly{alpha} emission at 1.9<z<3.8, and the majority of the remainder objects are low-redshift [OII]3727 emitters at z<0.56. The classification between low- and high-redshift objects depends on rest-frame equivalent width (EW), as well as other indicators, where available. Based on matches to X-ray catalogs, the active galactic nuclei fraction among the Ly{alpha} emitters is 6%. We also analyze the survey's completeness and contamination properties through simulations. We find five high-z, highly significant, resolved objects with FWHM sizes >44arcmin^2^ which appear to be extended Ly{alpha} nebulae. We also find three high-z objects with rest-frame Ly{alpha} EW above the level believed to be achievable with normal star formation, EW0>240{AA}.
- ID:
- ivo://CDS.VizieR/J/AJ/138/1022
- Title:
- Emission-line galaxies from HST PEARS survey
- Short Name:
- J/AJ/138/1022
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of a search for emission-line galaxies (ELGs) in the southern fields of the Hubble Space Telescope Probing Evolution And Reionization Spectroscopically (PEARS) grism survey. The PEARS South Fields consist of five Advanced Camera for Surveys pointings (including the Hubble Ultra Deep Field) with the G800L grism for a total of 120 orbits, revealing thousands of faint object spectra in the GOODS-South region of the sky. ELGs are one subset of objects that are prevalent among the grism spectra. Using a two-dimensional detection and extraction procedure, we find 320 emission lines originating from 226 galaxy "knots" within 192 individual galaxies. Line identification results in 118 new grism-spectroscopic redshifts for galaxies in the GOODS-South Field. We measure emission-line fluxes using standard Gaussian fitting techniques. The star formation rates of the ELGs are presented, as well as a sample of distinct giant star-forming regions at z~0.1-0.5 across individual galaxies.
