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741. 22 extreme [OIII] emitters at z~0.5 from SDSS-DR14
ID:
ivo://CDS.VizieR/J/ApJ/860/83
Title:
22 extreme [OIII] emitters at z~0.5 from SDSS-DR14
Short Name:
J/ApJ/860/83
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have found a sample of extreme emission-line galaxies (EELGs) with strong [OIII]{lambda}5007 emission at z~0.5. Using broadband photometric selection and requiring small uncertainties in photometry, we searched the 14th Data Release of the Sloan Digital Sky Survey (SDSS) and found 2658 candidates with strong i-band excess (i-z<=r-i-0.7). We further obtained 649 SDSS spectra of these objects, and visually identified 22 [OIII] emitters lying at 0.40<z<0.63. Having constructed their ultraviolet-infrared spectral energy distributions, we found that they have fairly blue r-W2 and red W1-W4 colors, indicative of strong, warm dust emission. Their rest-frame [OIII]{lambda}5007 equivalent widths are mostly 200-600{AA}, and their high [OIII]{lambda}5007/H{beta} ratios put them at the boundary of star-forming galaxies and active galactic nuclei on line ratio classification diagrams. The typical E(B-V) and electron temperature of [OIII] emitters are ~0.1-0.3mag and ~104K, respectively. The lowest metallicity of our [OIII] emitters with S/N[OIII]{lambda}4363>3 is 12+log(O/H)=7.98_-0.02_^+0.12^, with a median value of 8.24_-0.04_^+0.05^. Our [OIII] emitters exhibit remarkably high line luminosity-18/22 have L[OIII]{lambda}5007>5x10^42^erg/s and 5/22 have L[OIII]{lambda}5007>10^43^erg/s. Their estimated volume number density at z~0.5 is ~2x10^-8^Mpc^-3^, with L[OIII]{lambda}5007 down to ~3x10^42^erg/s. The cumulative number distribution of EELGs across different redshifts is indicative of a strong redshift evolution at the bright end of the [OIII] luminosity function.
742. EZ CMa spectroscopy
ID:
ivo://CDS.VizieR/J/A+A/347/583
Title:
EZ CMa spectroscopy
Short Name:
J/A+A/347/583
Date:
21 Oct 2021
Publisher:
CDS
Description:
The table contains the window averaged flux (WAF) in two windows located at the P Cyg absorption component of the NV 4604/4620 doublet and the kurtosis of the HeII 4540 and HeII 4686 lines of the star EZ CMa. The three data sets are stored in three different files with the same format.
743. Faint Emission Lines and Temperature
ID:
ivo://CDS.VizieR/J/ApJS/120/113
Title:
Faint Emission Lines and Temperature
Short Name:
J/ApJS/120/113
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present echelle spectroscopy in the 3500-10300{AA} range of the Hourglass Nebula, which is embedded in the Galactic H II region M8. The data were obtained using the 2.1m telescope at Observatorio Astronomico Nacional in San Pedro Mqrtir, Baja California. We have measured the intensities of 274 emission lines, in particular 88 permitted lines of C^+^, N^0^, N^+^, O^0^, O^+^, Ne^0^, S^0^, S^+^, Si^0^, Si^+^, and Si^++^, some of them produced by recombination only and others mainly by fluorescence. We have determined electron temperatures and densities using different line intensity ratios. We derive the He^+^, C^++^, O^+^, and O^++^ ionic abundances as well as - for the first time in a nebular object - the total O abundance from recombination lines; these nebular values are independent of the temperature structure of the nebula. We have also derived abundances from collisionally excited lines for a large number of ions and elements; these abundances do depend on the temperature structure. Accurate t^2^ values have been derived by comparing the C^++^, O^+^, and O^++^ ionic abundances obtained making use of both collisionally excited lines and recombination lines. A comparison of the solar, Orion Nebula, and M8 chemical abundances is made.
744. Faint emission lines in M16, M20, NGC 3603
ID:
ivo://CDS.VizieR/J/MNRAS/368/253
Title:
Faint emission lines in M16, M20, NGC 3603
Short Name:
J/MNRAS/368/253
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep echelle spectrophotometry of the Galactic HII regions M16, M20 and NGC 3603. The data have been taken with the Very Large Telescope Ultraviolet-Visual Echelle Spectrograph in the 3100-10400{AA} range. We have detected more than 200 emission lines in each region. Physical conditions have been derived using different continuum and line intensity ratios. We have derived He^+^, C^++^ and O^++^ abundances from pure recombination lines as well as collisionally excited lines (CELs) for a large number of ions of different elements.
745. Faint galactic satellites spectroscopic survey
ID:
ivo://CDS.VizieR/J/MNRAS/380/281
Title:
Faint galactic satellites spectroscopic survey
Short Name:
J/MNRAS/380/281
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a spectroscopic survey of the recently discovered faint Milky Way satellites Bootes, Ursa Major I, Ursa Major II and Willman 1 (Wil1). Using the DEep Imaging Multi-Object Spectrograph mounted on the Keck II telescope, we have obtained samples that contain from ~15 to ~85 probable members of these satellites for which we derive radial velocities precise to a few km/s down to i~21-22. About half of these stars are observed with a high enough signal-to-noise ratio to estimate their metallicity to within +/-0.2dex. The characteristics of all the observed stars are made available, along with those of the Canes Venatici I dwarf galaxy that have been analysed in a companion paper.
746. Faint, high-Galactic-latitude red clump stars
ID:
ivo://CDS.VizieR/J/A+A/522/A79
Title:
Faint, high-Galactic-latitude red clump stars
Short Name:
J/A+A/522/A79
Date:
21 Oct 2021
Publisher:
CDS
Description:
With this survey we aim to derive accurate, multi-epoch radial velocities and atmospheric parameters (Teff, logg, [M/H] and V_rot_sini) of a large sample of carefully selected red clump (RC) stars located over a great circle at high Galactic latitudes. We acquired data of the program stars of high signal-to-noise ratio and high resolution with the Asiago Echelle spectrograph. We obtained radial velocities by applying cross-correlation and atmospheric parameters via chi2 fitting to a synthetic spectral library. Extensive tests were carried out by re-observing with the same instrument a large number of standard stars taken from a variety of sources in literature.
747. Faint, high-Galactic-latitude red clump stars
ID:
ivo://CDS.VizieR/J/A+A/527/A40
Title:
Faint, high-Galactic-latitude red clump stars
Short Name:
J/A+A/527/A40
Date:
21 Oct 2021
Publisher:
CDS
Description:
The goal of our survey is to provide accurate and multi-epoch radial velocities, atmospheric parameters (Teff, logg and [M/H]), distances, and space velocities of faint red clump (RC) stars. We recorded high signal-to-noise (S/N>=200) spectra of RC stars over the 4750-5950{AA} range at a resolving power 5500. The target stars are distributed across the great circle of the celestial equator. Radial velocities were obtained via cross-correlation with IAU radial velocity standards. Atmospheric parameters were derived via {chi}^2^ fit to a synthetic spectral library. A large number of RC stars from other surveys were re-observed to check the consistency of our results and the absence of offsets and trends.
748. Faint planetary nebulae in Magellanic Clouds
ID:
ivo://CDS.VizieR/J/ApJ/417/209
Title:
Faint planetary nebulae in Magellanic Clouds
Short Name:
J/ApJ/417/209
Date:
21 Oct 2021
Publisher:
CDS
Description:
The accuracy of spectrophotometry for Magellanic Cloud planetary nebulae is limited by a number of physical effects and operational difficulties: atmospheric dispersion, wavelength-dependent seeing, pointing and guiding errors, and a background of numerous stars and diffuse emission. We describe procedures to minimize the impact of some of these. We then compare our results for both bright and faint objects with published values. There are a few exceptional cases (e.g., LMC 89), but generally we find that bright planetary nebulae in the Clouds have been observed with high accuracy. On the other hand, observations of the faint sample from Jacoby (1980ApJS...42....1J) suffer seriously from many of these effects. We also compare published {lambda}5007 photometry with new CCD photometry for nine faint planetary nebulae. We find the photographic photometry presented by Jacoby (1980ApJS...42....1J) to be accurate to 0.26mag. Fluxes for the fainter objects that are derived from spectrophotometry (Boroson & Liebert, 1989ApJ...339..844B) are found to be less reliable. In comparison, spectrophotometry using the observational techniques presented in this paper provides reliable absolute fluxes. With these improved observations, we review the correlations presented by Kaler & Jacoby (1990ApJ...362..491K, 1991ApJ...382..134K) between abundance ratios and central star mass. The new results fit our earlier correlation for N/O, strengthen that for He/H, and change little about those for C/O and O/H.
749. Faint red galaxies in Coma cluster spectroscopy
ID:
ivo://CDS.VizieR/J/MNRAS/392/1265
Title:
Faint red galaxies in Coma cluster spectroscopy
Short Name:
J/MNRAS/392/1265
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the stellar populations in a sample of 89 faint red galaxies in the Coma cluster, using high signal-to-noise ratio (S/N) spectroscopy from the 6.5-m MMT. Our sample is drawn from two 1{deg} fields, one centred on the cluster core and the other located 1{deg} to the south-west of the cluster centre. The target galaxies are mostly 2-4mag fainter than M*; galaxies with these luminosities have been previously studied only using small samples, or at low S/N. For a comparison sample we use published high-S/N data for red-sequence galaxies in the Shapley supercluster. We use state-of-the-art stellar population models (by R. Schiavon, Cat. <J/ApJS/171/146>) to interpret the absorption-line indices and infer the single-burst-equivalent age and metallicity (Fe/H) for each galaxy, as well as the abundances of the light elements Mg, Ca, C and N.
750. Fairly bright slow rotators chemical compositions
ID:
ivo://CDS.VizieR/J/AJ/158/157
Title:
Fairly bright slow rotators chemical compositions
Short Name:
J/AJ/158/157
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on a detailed abundance study of the fairly bright slow rotators HD 30085 (A0 IV), HD 30963 (B9 III), and HD 174567 (A0 V), hitherto reported as normal stars and the sharp-lined {chi} Lupi A (B9 IV HgMn). In the spectra of HD 30085 and HD 30963, the Hg II line at 3984 {AA} is conspicuous and numerous lines of silicon, manganese, chromium, titanium, iron, strontium, yttrium, and zirconium appear to be strong absorbers. A comparison of the mean spectra of HD 30085 and HD 30963 with a grid of synthetic spectra for selected unblended lines having reliable updated atomic data reveals large overabundances of phosphorus, titanium, chromium, manganese, strontium, yttrium, zirconium, barium, platinum, and mercury, and underabundances of helium, magnesium, scandium, and nickel. The surface abundances of {chi} Lupi A have been rederived on the same effective temperature scale and using the same atomic data for consistency and comparison for HD 30085 and HD 30963. For HD 174567, milder deficiencies and excesses are found. The abundances of sodium, magnesium, and calcium have been corrected for non-LTE (NLTE) effects. The effective temperatures, surface gravities, low projected rotational velocities, and the peculiar abundance patterns of HD 30085 and HD 30963 show that these stars are two new HgMn stars and should be reclassified as such. HD 174567 is most likely a new marginally chemically peculiar star. A list of the identifications of lines absorbing more than 2% in the spectrum of HD 30085 is also provided.

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