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3751. The distance modulus of the LMC
ID:
ivo://CDS.VizieR/J/A+A/363/L1
Title:
The distance modulus of the LMC
Short Name:
J/A+A/363/L1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use double-mode RR Lyrae (RRd) stars from the MACHO variable star database of the Large Magellanic Cloud (LMC) to estimate its distance, by utilizing photometric data, linear pulsation and stellar atmosphere models. If we set E_(B-V)_=0.11 and [M/H]=-1.5 for LMC, we get M-m=18.52mag. The fact that the distance moduli obtained in this and in our former studies of cluster RRd and Small Magellanic Cloud beat Cepheids agree so well, implies that the only serious source of error is the zero point of the temperature scale, which should not have larger than +/-0.10mag effect on the distance modulus.
3752. The Extended 12um galaxy sample
ID:
ivo://CDS.VizieR/VII/157
Title:
The Extended 12um galaxy sample
Short Name:
VII/157
Date:
21 Oct 2021
Publisher:
CDS
Description:
The authors have used the IRAS data to compile a sample of 893 galaxies, including 118 Seyfert galaxies. Please refer to the "12micron.doc" (ascii) or "12micron.tex" (LaTeX) file for complete descriptions.
3753. The Extended Virgo Cluster Catalog (EVCC)
ID:
ivo://CDS.VizieR/J/ApJS/215/22
Title:
The Extended Virgo Cluster Catalog (EVCC)
Short Name:
J/ApJS/215/22
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new catalog of galaxies in the wider region of the Virgo cluster, based on the Sloan Digital Sky Survey (SDSS) Data Release 7. The Extended Virgo Cluster Catalog (EVCC) covers an area of 725deg^2^ or 60.1Mpc^2^. It is 5.2 times larger than the footprint of the classical Virgo Cluster Catalog (VCC) and reaches out to 3.5 times the virial radius of the Virgo cluster. We selected 1324 spectroscopically targeted galaxies with radial velocities less than 3000km/s. In addition, 265 galaxies that have been overlooked in the SDSS spectroscopic survey but have available redshifts in the NASA Extragalactic Database are also included. Our selection process secured a total of 1589 galaxies, 676 of which are not included in the VCC. The certain and possible cluster members are defined by means of redshift comparison with a cluster infall model. We employed two independent and complementary galaxy classification schemes: the traditional morphological classification based on the visual inspection of optical images and a characterization of galaxies from their spectroscopic features. SDSS u, g, r, i, and z passband photometry of all EVCC galaxies was performed using Source Extractor. We compare the EVCC galaxies with the VCC in terms of morphology, spatial distribution, and luminosity function. The EVCC defines a comprehensive galaxy sample covering a wider range in galaxy density that is significantly different from the inner region of the Virgo cluster. It will be the foundation for forthcoming galaxy evolution studies in the extended Virgo cluster region, complementing ongoing and planned Virgo cluster surveys at various wavelengths.
3754. The EZOA survey
ID:
ivo://CDS.VizieR/J/MNRAS/489/2907
Title:
The EZOA survey
Short Name:
J/MNRAS/489/2907
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of galaxies in the northern Zone of Avoidance (ZoA), extracted from the shallow version of the blind HI survey with the Effelsberg 100m radio telescope, EBHIS, that has a sensitivity of 23mJy/beam at 10.24km/s velocity resolution. The catalogue comprises 170 detections in the region Dec>=-5{deg} and |b|<6{deg}. About a third of the detections (N=67) have not been previously recorded in HI. While 29 detections have no discernible counterpart at any wavelength other than HI, 48 detections (28%) have a counterpart visible on optical or NIR images but are not recorded as such in the literature. New HI detections were found as close as 7.5Mpc (EZOA J2120+45), and at the edge of the Local Volume, at 10.1Mpc, we have found two previously unknown dwarf galaxies (EZOA J0506+31 and EZOA J0301+56). Existing large-scale structures crossing the northern ZoA have been established more firmly by the new detections, with the possibility of new filaments. We conclude that the high rate of 39% new HI\detections in the northern ZoA, which has been extensively surveyed with targeted observations in the past, proves the power of blind HI surveys. The full EBHIS survey, which will cover the full northern sky with a sensitivity comparable to the HIPASS survey of the southern sky, is expected to add many new detections and uncover new structures in the northern ZoA.
3755. The FIRST bright quasar survey. II.
ID:
ivo://CDS.VizieR/J/ApJS/126/133
Title:
The FIRST bright quasar survey. II.
Short Name:
J/ApJS/126/133
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have used the Very Large Array (VLA) FIRST survey and the Automated Plate Measuring Facility (APM) catalog of the Palomar Observatory Sky Survey I (POSS-I) plates as the basis for constructing a new radio-selected sample of optically bright quasars. This is the first radio-selected sample that is competitive in size with current optically selected quasar surveys. Using only two basic criteria, radio-optical positional coincidence and optical morphology, quasars and BL Lac objects can be identified with 60% selection efficiency; the efficiency increases to 70% for objects fainter than 17 mag. We show that a more sophisticated selection scheme can predict with better than 85% reliability which candidates will turn out to be quasars. This paper presents the second installment of the FIRST Bright Quasar Survey (FBQS), with a catalog of 636 quasars distributed over 2682 deg^2^. The quasar sample is characterized and all spectra are displayed.
3756. The FIRST bright quasar survey. III.
ID:
ivo://CDS.VizieR/J/ApJS/135/227
Title:
The FIRST bright quasar survey. III.
Short Name:
J/ApJS/135/227
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of an extension of the FIRST Bright Quasar Survey (FBQS) to the South Galactic cap, and to a fainter optical magnitude limit. Radio source counterparts with SERC R magnitudes brighter than 18.9 which meet the other FBQS criteria are included. We supplement this list with a modest number of additional objects to test our completeness for quasars with extended radio morphologies. The survey covers 589deg^2^ in two equatorial strips in the southern cap. We have obtained spectra for 86% of the 522 candidates and find 321 radio-selected quasars of which 264 are reported here for the first time. A comparison of this fainter sample with the FBQS sample shows the two to be generally similar. Fourteen new broad absorption line (BAL) quasars are included in this sample. When combined with the previously identified BAL quasars in our earlier papers, we can discern a break in the frequency of BAL quasars with radio loudness, namely that the relative number of high-ionization BAL quasars drops by a factor of 4 for quasars with a radio-loudness parameter R*>100.
3757. The First CEMP star in the Sculptor dSph
ID:
ivo://CDS.VizieR/J/A+A/574/A129
Title:
The First CEMP star in the Sculptor dSph
Short Name:
J/A+A/574/A129
Date:
04 Feb 2022 11:54:02
Publisher:
CDS
Description:
he origin of carbon-enhanced metal-poor (CEMP) stars and their possible connection with the chemical elements produced by the first stellar generation is still highly debated. In contrast to the Galactic halo, not many CEMP stars have been found in the dwarf spheroidal galaxies around the Milky Way. Here we present detailed abundances from ESO VLT/UVES high-resolution spectroscopy for ET0097, the first CEMP star found in the Sculptor dwarf spheroidal, which is one of the best studied dwarf galaxies in the Local Group. This star has [Fe/H]=-2.03+/-0.10, [C/Fe]=0.51+/-0.10 and [N/Fe]=1.18+/-0.20, which is the first nitrogen measurement in this galaxy. The traditional definition of CEMP stars is [C/Fe]>=0.70, but taking into account that this luminous red giant branch star has undergone mixing, it was intrinsically less nitrogen enhanced and more carbon-rich when it was formed, and so it falls under the definition of CEMP stars, as proposed by Aoki et al. (2007ApJ...655..492A, Cat. J/ApJ/655/492) to account for this effect.
3758. The FIRST sample of ultraluminous IR galaxies
ID:
ivo://CDS.VizieR/J/ApJS/131/185
Title:
The FIRST sample of ultraluminous IR galaxies
Short Name:
J/ApJS/131/185
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new sample of distant ultraluminous infrared galaxies. The sample was selected from a positional cross-correlation of the IRAS Faint Source Catalog (Cat. <II/156>) with the FIRST database. Objects from this set were selected for spectroscopy by virtue of following the well-known star-forming galaxy correlation between 1.4 GHz and 60 {mu}m flux, and by being optically faint on the POSS. Optical identification and spectroscopy were obtained for 108 targets at the Lick Observatory 3 m telescope.
3759. The FLAMINGOS Extragalactic Survey
ID:
ivo://CDS.VizieR/J/ApJ/639/816
Title:
The FLAMINGOS Extragalactic Survey
Short Name:
J/ApJ/639/816
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the Florida Multi-object Imaging Near-IR Grism Observational Spectrometer (FLAMINGOS), we have conducted the FLAMINGOS Extragalactic Survey (FLAMEX), a deep imaging survey covering 7.1{deg}^2^ within the 18.6{deg}^2^ NOAO Deep Wide-Field Survey (NDWFS) regions. FLAMEX is the first deep, wide-area, nearinfrared survey to image in both the J and Ks filters, and is larger than any previous NIR survey of comparable depth. The intent of FLAMEX is to facilitate the study of galaxy and galaxy cluster evolution at 1<z<2 by providing rest-frame optical photometry for the massive galaxy population at this epoch. This effort is designed to yield a public data set that complements and augments the suite of existing surveys in the NDWFS fields. We present an overview of FLAMEX and initial results based on ~150,000 Ks-selected sources in the Bootes field. We describe the observations and reductions, quantify the data quality, and verify that the number counts are consistent with results from previous surveys. Finally, we comment on the utility of this sample for detailed study of the ERO population, and present one of the first spectroscopically confirmed z>1 galaxy clusters detected using the joint FLAMEX, NDWFS, and Spitzer IRAC Shallow Survey data sets.
3760. The Fornax Deep Survey with the VST. IX.
ID:
ivo://CDS.VizieR/J/A+A/639/A136
Title:
The Fornax Deep Survey with the VST. IX.
Short Name:
J/A+A/639/A136
Date:
21 Oct 2021
Publisher:
CDS
Description:
A possible pathway for understanding the events and the mechanisms involved in galaxy formation and evolution is an in-depth comprehension of the galactic and inter-galactic fossil sub-structures with long dynamical times-scales: stars in the field and in stellar clusters. This paper continues the series of the Fornax Deep Survey (FDS). Following the previous studies dedicated to extended Fornax cluster members, in this paper we present the catalogs of compact stellar systems in the Fornax cluster as well as extended background sources and point-like sources. We derive ugri photometry of ~1.7 million sources over the ~21 square degree area of FDS centered on the bright central galaxy NGC1399. For a wider area, of ~27 square degrees extending in the direction of NGC1316, we provide gri photometry for ~3.1 million sources. To improve the morphological characterization of sources we generate multi-band image stacks by coadding the best seeing gri-band single exposures with a cut at FWHM<=0.9". We use the multi-band stacks as master detection frames, with a FWHM improved by ~15% and a FWHM variability from field to field reduced by a factor of ~2.5 compared to the pass-band with best FWHM, namely the r-band. The identification of compact sources, in particular of globular clusters (GC), is obtained from a combination of photometric (e.g. colors, magnitudes) and morphometric (e.g. concentration index, elongation, effective radius) selection criteria, by also taking as reference the properties of sources with well-defined classification from spectroscopic or high-resolution imaging data. Using the FDS catalogs, we present a preliminary analysis of globular cluster (GC) distributions in the Fornax area. The study confirms and extends further previous results which were limited to a smaller survey area. We observe the inter-galactic population of GCs, a population of mainly blue GCs centered on NGC1399, extends over ~0.9Mpc, with an ellipticity ~0.65 and a small tilt in the direction of NGC1336. Several sub-structures extend over ~0.5Mpc along various directions. Two of these structures do not cross any bright galaxy; one of them appears to be connected to NGC1404, a bright galaxy close to the cluster core and particularly poor of GCs. Using the gri catalogs we analyze the GC distribution over the extended FDS area, and do not find any obvious GC sub-structure bridging the two brightest cluster galaxies, NGC1316 and NGC1399. Although NGC1316 is more than twice brighter of NGC1399 in optical bands, using gri data, we estimate a factor of ~3-4 richer GC population around NGC1399 compared to NGC1316, out to galactocentric distances of ~40' or ~230kpc