- 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.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/811/78
- Title:
- Elemental depletions in the Magellanic Clouds
- Short Name:
- J/ApJ/811/78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of the composition of gas and dust in the Large and Small Magellanic Clouds (LMC and SMC) using UV absorption spectroscopy. We measure PII and FeII along 84 spatially distributed sightlines toward the MCs using archival Far Ultraviolet Spectroscopic Explorer observations. For 16 of those sightlines, we also measure SiII, CrII, and ZnII from new Hubble Space Telescope Cosmic Origins Spectrograph observations. We analyze these spectra using a new spectral line analysis technique based on a semi-parametric Voigt profile model. We have combined these measurements with HI and H_2_ column densities and reference stellar abundances from the literature to derive gas-phase abundances, depletions, and gas-to-dust ratios (GDRs). Of our 84 P and 16 Zn measurements, 80 and 13, respectively, are depleted by more than 0.1dex, suggesting that P and Zn abundances are not accurate metallicity indicators at and above the metallicity of the SMC. Si, Cr, and Fe are systematically less depleted in the SMC than in the Milky Way (MW) or LMC. The minimum Si depletion in the SMC is consistent with zero. We find GDR ranges of 190-565 in the LMC and 480-2100 in the SMC, which is broadly consistent with GDRs from the literature. These ranges represent actual location to location variation and are evidence of dust destruction and/or growth in the diffuse neutral phase of the interstellar medium. Where they overlap in metallicity, the gas-phase abundances of the MW, LMC, and SMC and damped Ly{alpha} systems evolve similarly with metallicity.
- 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/894/53
- Title:
- ELM Survey South. I. RVs for 6 new ELM WDs
- Short Name:
- J/ApJ/894/53
- Date:
- 22 Oct 2021 08:25:16
- Publisher:
- CDS
- Description:
- We begin the search for extremely low mass (M<=0.3M_{sun}_, ELM) white dwarfs (WDs) in the southern sky based on photometry from the VST ATLAS and SkyMapper surveys. We use a similar color selection method as the Hypervelocity star survey. We switched to an astrometric selection once Gaia Data Release 2 became available. We use the previously known sample of ELM white dwarfs to demonstrate that these objects occupy a unique parameter space in parallax and magnitude. We use the SOAR 4.1m telescope to test the Gaia-based selection, and identify more than two dozen low mass white dwarfs, including six new ELM white dwarf binaries with periods as short as 2h. The better efficiency of the Gaia-based selection enables us to extend the ELM Survey footprint to the southern sky. We confirm one of our candidates, J0500-0930, to be the brightest (G=12.6mag) and closest (d=72pc) ELM white dwarf binary currently known. Remarkably, the Transiting Exoplanet Survey Satellite (TESS) full-frame imaging data on this system reveals low-level (<0.1%) but significant variability at the orbital period of this system (P=9.5hr), likely from the relativistic beaming effect. TESS data on another system, J0642-5605, reveals ellipsoidal variations due to a tidally distorted ELM WD. These demonstrate the power of TESS full-frame images in confirming the orbital periods of relatively bright compact object binaries.
665. ELODIE archive
- ID:
- ivo://CDS.VizieR/III/218
- Title:
- ELODIE archive
- Short Name:
- III/218
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a database of 908 stellar spectra of 709 stars in the wavelength range 410 to 680 nm obtained with the ELODIE spectrograph. The archive provides a large coverage of the space of stellar parameters: Spectral types O to M, luminosity classes V to I and metallicities [Fe/H] from -3.0 to +0.8. At the nominal resolution, R=42000, the mean signal-to-noise ratio is 150 per pixel. The spectra given at this resolution are normalized to their pseudo-continuum and are intended to serve for abundance studies, spectral classification and tests of stellar atmosphere models. A lower resolution version of the archive, R=10000, is calibrated in physical flux with a broad-band photometric precision of 2.5% and narrow-band precision of 0.5%. It is scoped for stellar population synthesis of galaxies and clusters, and for kinematical investigations of stellar systems. The archive is also distributed in FITS format through the HYPERCAT database http://www-obs.univ-lyon1.fr/hypercat/spectrophotometry.html .
666. ELODIE archive
- ID:
- ivo://obs-hp.fr/elodie/ssa
- Title:
- ELODIE archive
- Short Name:
- ELODIE
- Date:
- 15 Apr 2008 20:18:49
- Publisher:
- Observatoire de Haute-Provence
- Description:
- The science archive of the ELODIE spectrograph contains all the spectra collected by the instrument between 1993 and 2006 (total life time of the instrument). ELODIE is an echelle spectrograph providing a resolution R=42000 in the spectral range 390-680 nm. The web interface of the archive distribute a variety of products, and the SSA service gives the reconnected 1D spectra in instrumental flux (not physical). This service is given for test: The spectra cannot be viewved with VOSpec because they are not flux-calibrated.
667. ELODIE library V3.1
- ID:
- ivo://CDS.VizieR/III/251
- Title:
- ELODIE library V3.1
- Short Name:
- III/251
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- ELODIE.3.1 is an updated release of the library published in Prugniel & Soubiran (2001A&A...369.1048P, Cat. III/218; and 2004 version, in astro-ph/0409214). The library includes 1959 spectra of 1388 stars obtained with the ELODIE spectrograph at the Observatoire de Haute-Provence 193cm telescope in the wavelength range 390 to 680 nm. It provides a wide coverage of atmospheric parameters: Teff from 3100K to 50000K, logg from -0.25 to 4.9 and [Fe/H] from -3 to +1. The library is given at two resolutions: R around 42000, with the flux normalized to the pseudo-continuum. A lower resolution version of the spectra (R around 10000), is calibrated in physical flux (reduced above earth atmosphere) with a broad-band photometric precision of 2.5% and narrow-band precision of 0.5%. In this new release the data-reduction (flux calibration, reconnection of the echelle orders) has been improved, and in particular the blue region, between 390 and 400nm has been added. The FITS files for each spectra, and the measured atmospheric parameters are publicly available. See the ELODIE.3.1 page for more details: http://www.obs.u-bordeaux1.fr/m2a/soubiran/elodie library.html
- ID:
- ivo://CDS.VizieR/J/ApJ/871/258
- Title:
- ELQS in SDSS. III. The full ELQS quasar catalog
- Short Name:
- J/ApJ/871/258
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have designed the Extremely Luminous Quasar Survey (ELQS) to provide a highly complete census of unobscured UV-bright quasars during the cosmic noon, z=2.8-5.0. Here we report the discovery of 70 new quasars in the ELQS South Galactic Cap (ELQS-S) quasar sample, doubling the number of known extremely luminous quasars in 4237.3deg^2^ of the Sloan Digital Sky Survey footprint. These observations conclude the ELQS and we present the properties of the full ELQS quasar catalog, containing 407 quasars over 11838.5deg^2^. Our novel ELQS quasar selection strategy resulted in unprecedented completeness at the bright end and allowed us to discover 109 new quasars in total. This marks an increase of ~36% (109/298) in the known population at these redshifts and magnitudes, while we further are able to retain a selection efficiency of ~80%. On the basis of 166 quasars from the full ELQS quasar catalog, which adhere to the uniform criteria of the Two Micron All Sky Survey point source catalog, we measure the bright-end quasar luminosity function (QLF) and extend it one magnitude brighter than previous studies. Assuming a single power law with exponential density evolution for the functional form of the QLF, we retrieve the best-fit parameters from a maximum likelihood analysis. We find a steep bright-end slope of {beta}~-4.1, and we can constrain the bright-end slope to {beta}<=-3.4 with 99% confidence. The density is well modeled by the exponential redshift evolution, resulting in a moderate decrease with redshift ({gamma}~-0.4).
- ID:
- ivo://CDS.VizieR/J/A+A/620/A30
- Title:
- 12 embedded protostellar systems APEX spectra
- Short Name:
- J/A+A/620/A30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Simulations suggest that gas heating due to radiative feedback is a key factor in whether or not multiple protostellar systems will form. Chemistry is a good tracer of the physical structure of a protostellar system, since it depends on the temperature structure. We aim to study the relationship between envelope gas temperature and protostellar multiplicity. Single dish observations of various molecules that trace the cold, warm and UV-irradiated gas are used to probe the temperature structure of multiple and single protostellar systems on 7000 AU scales. Single, close binary, and wide multiples present similar current envelope gas temperatures, as estimated from H_2_CO and DCO^+^ line ratios. The temperature of the outflow cavity, traced by c-C_3_H_2_, on the other hand, shows a relation with bolometric luminosity and an anticorrelation with envelope mass. Although the envelope gas temperatures are similar for all objects surveyed, wide multiples tend to exhibit a more massive reservoir of cold gas compared to close binary and single protostars. Although the sample of protostellar systems is small, the results suggest that gas temperature may not have a strong impact on fragmentation. We propose that mass, and density, may instead be key factors in fragmentation.
- ID:
- ivo://CDS.VizieR/J/ApJS/149/157
- Title:
- EMILI line-identification in IC 418 spectrum
- Short Name:
- J/ApJS/149/157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The identification of spectral lines can be a tedious process requiring the interrogation of large spectroscopic databases, but it does lend itself to software algorithms that can determine the characteristics of candidate line identifications. We present here criteria used for the identification of lines and a logic developed for a line identification software package called EMILI, which uses the v2.04 Atomic Line List as the basic line database. EMILI considers all possible database transitions within the wavelength uncertainties for observed optical emission lines and computes an approximate intensity for each candidate line. It searches for other multiplet members that are expected to be seen with each candidate line, and rank-orders all of the tentative line identifications for each observed line based on a set of criteria. When applied to the spectra of the Orion Nebula and the planetary nebula IC 418, EMILI's recommended line IDs agree well with those of previous traditional manual line assignments. The existence of a semiautomated procedure should give impetus to the study of very high signal-to-noise spectra, enabling the identification of previously unidentified spectral lines to be handled with ease and consistency.