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1181. MUSYC optical imaging in ECDF-S
ID:
ivo://CDS.VizieR/J/ApJS/189/270
Title:
MUSYC optical imaging in ECDF-S
Short Name:
J/ApJS/189/270
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep optical 18-medium-band photometry from the Subaru telescope over the ~30'x30' Extended Chandra Deep Field-South, as part of the Multiwavelength Survey by Yale-Chile (MUSYC). This field has a wealth of ground- and space-based ancillary data, and contains the GOODS-South field and the Hubble Ultra Deep Field. We combine the Subaru imaging with existing UBVRIzJHK and Spitzer IRAC images to create a uniform catalog. Detecting sources in the MUSYC "BVR" image we find ~40,000 galaxies with R_AB_<25.3, the median 5{sigma} limit of the 18 medium bands. Photometric redshifts are determined using the EAzY code and compared to ~2000 spectroscopic redshifts in this field. The medium-band filters provide very accurate redshifts for the (bright) subset of galaxies with spectroscopic redshifts, particularly at 0.1<z<1.2 and at z~>3.5. For 0.1<z<1.2, we find a 1{sigma} scatter in {DELTA}z/(1+z) of 0.007, similar to results obtained with a similar filter set in the COSMOS field. As a demonstration of the data quality, we show that the red sequence and blue cloud can be cleanly identified in rest-frame color-magnitude diagrams at 0.1<z<1.2. We find that ~20% of the red sequence galaxies show evidence of dust emission at longer rest-frame wavelengths. The reduced images, photometric catalog, and photometric redshifts are provided through the public MUSYC Web site (http://www.astro.yale.edu/MUSYC/).
1182. MYStIX candidate protostars
ID:
ivo://CDS.VizieR/J/ApJ/833/193
Title:
MYStIX candidate protostars
Short Name:
J/ApJ/833/193
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Massive Young Star-Forming Complex in Infrared and X-ray (MYStIX) project provides a new census on stellar members of massive star-forming regions within 4kpc. Here the MYStIX Infrared Excess catalog and Chandra-based X-ray photometric catalogs are mined to obtain high-quality samples of Class I protostars using criteria designed to reduce extragalactic and Galactic field star contamination. A total of 1109 MYStIX Candidate Protostars (MCPs) are found in 14 star-forming regions. Most are selected from protoplanetary disk infrared excess emission, but 20% are found from their ultrahard X-ray spectra from heavily absorbed magnetospheric flare emission. Two-thirds of the MCP sample is newly reported here. The resulting samples are strongly spatially associated with molecular cores and filaments on Herschel far-infrared maps. This spatial agreement and other evidence indicate that the MCP sample has high reliability with relatively few "false positives" from contaminating populations. But the limited sensitivity and sparse overlap among the infrared and X-ray subsamples indicate that the sample is very incomplete with many "false negatives." Maps, tables, and source descriptions are provided to guide further study of star formation in these regions. In particular, the nature of ultrahard X-ray protostellar candidates without known infrared counterparts needs to be elucidated.
1183. Nainital-Cape Survey. IV.
ID:
ivo://CDS.VizieR/J/A+A/590/A116
Title:
Nainital-Cape Survey. IV.
Short Name:
J/A+A/590/A116
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Nainital-Cape Survey is a dedicated ongoing Survey programme to search for and study pulsational variability in chemically peculiar (CP) stars to understand their internal structure and evolution. The main aims of this Survey are to find new pulsating Ap and Am stars in the northern and southern hemisphere and to perform asteroseismic studies of these new pulsators. The Survey is conducted using high-speed photometry. The candidate stars were selected on the basis of having Stromgren photometric indices similar to those of known pulsating CP stars. Over the last decade a total of 337 candidate pulsating CP stars were observed for the Nainital-Cape Survey, making it one of the longest ground-based surveys for pulsation in CP stars in terms of time span and sample size. The previous papers of this series presented seven new pulsating variables and 229 null results. In this paper we present the light curves, frequency spectra and various astrophysical parameters of the 108 additional CP stars observed since the last reported results. We also tabulated the basic physical parameters of the known roAp stars. As a part of establishing the detection limits in the Nainital-Cape Survey, we investigated the scintillation noise level at the two observing sites used in this Survey, Sutherland and Nainital, by comparing the combined frequency spectra stars observed from each location. Our analysis shows that both the sites permit the detection of variations of the order of 0.6-milli-magnitude (mmag) in the frequency range 1-4mHz, Sutherland is on average marginally better.
1184. Narrow line Seyfert 1 galaxies from SDSS-DR3
ID:
ivo://CDS.VizieR/J/ApJS/166/128
Title:
Narrow line Seyfert 1 galaxies from SDSS-DR3
Short Name:
J/ApJS/166/128
Date:
21 Oct 2021
Publisher:
CDS
Description:
We carried out a systematic search for narrow line Seyfert 1 galaxies (NLS1s) from objects assigned as "QSOs" or "galaxies" in the spectroscopic sample of the Sloan Digital Sky Survey Data Release 3 (SDSS DR3) by a careful modeling of their emission lines and continua. The result is a uniform sample comprising ~2000 NLS1s. This sample dramatically increases the number of known NLS1s by a factor of ~10 over previous compilations. This paper presents the parameters of the prominent emission lines and continua, which were measured accurately with typical uncertainties <10%. Taking advantage of such an unprecedented large and uniform sample with accurately measured spectral parameters, we carried out various statistical analyses, some of which were only possible for the first time.
1185. Narrow MgII absorption lines from SDSS-DR9Q
ID:
ivo://CDS.VizieR/J/ApJS/221/32
Title:
Narrow MgII absorption lines from SDSS-DR9Q
Short Name:
J/ApJS/221/32
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the Data Release 9 Quasar spectra from the Baryonic Oscillation Spectroscopic Survey, which does not include quasar spectra from the Sloan Digital Sky Survey Data Release 7, we detect narrow MgII{lambda}{lambda}2796,2803 absorption doublets in the spectral data redward of 1250{AA} (quasar rest frame) until the red wing of the MgII{lambda}2800 emission line. Our survey is limited to quasar spectra with a median signal-to-noise ratio <S/N>{>=}4/pixel in the surveyed spectral region, resulting in a sample that contains 43260 quasars. We have detected a total of 18598 MgII absorption doublets with 0.2933<=z_abs_<=2.6529. About 75% of absorbers have an equivalent width at rest frame of W_r_^{lambda}2796^. About 75% of absorbers have doublet ratios (DR=W_r_^{lambda}2796^/W_r_^{lambda}2803^) in the range of 1<=DR<=2, and about 3.2% lie outside the range of 1-{sigma}_DR_<=DR<=2+{sigma}_DR_. We characterize the detection false positives/negatives by the frequency of detected MgII absorption doublets in the limits of the S/N of the spectral data. The S/N=4.5 limit is assigned a completeness fraction of 53% and tends to be complete when the S/N is greater than 4.5. The redshift number densities of all of the detected MgII absorbers moderately increase from z~0.4 to z~1.5, which parallels the evolution of the cosmic star formation rate density. Limiting our investigation to those quasars whose emission redshift can be determined from narrow emission lines, the relative velocities ({beta}) of MgII absorbers have a complex distribution which probably consists of three classes of MgII absorbers: (1) cosmologically intervening absorbers; (2) environmental absorbers that reside within the quasar host galaxies or galaxy clusters; (3) quasar outflow absorbers. After subtracting contributions from cosmologically intervening absorbers and environmental absorbers, the {beta} distribution of the MgII might mainly be contributed by the quasar outflow absorbers and peaks at {upsilon}~1500km/s. This peak velocity is lower than the value of 2000km/s found in statistical analysis of CIV absorbers.
1186. 2nd Digitized Sky Survey (Blue)
ID:
ivo://nasa.heasarc/skyview/dss2
Title:
2nd Digitized Sky Survey (Blue)
Short Name:
DSS2
Date:
25 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
<P> The native projection of these data is described as a high-order polynomial distortion of a gnomonic projection using the same terms as the DSS. Provenance: Data taken by ROE, AAO, and CalTech, Compression and distribution by Space Telescope Science Institute.. This is a service of NASA HEASARC.
1187. 2nd Epoch Molonglo Galactic Plane Survey (MGPS-2)
ID:
ivo://CDS.VizieR/VIII/82
Title:
2nd Epoch Molonglo Galactic Plane Survey (MGPS-2)
Short Name:
VIII/82
Date:
21 Oct 2021
Publisher:
CDS
Description:
The MGPS-2 (second epoch Molonglo Galactic Plane Survey) was carried out with the Molonglo Observatory Synthesis Telescope at a frequency of 843MHz and with a restoring beam of 45"x45"csd|{delta}|, making it he highest resolution large scale radio survey of the southern Galactic plane. It covers the range |b|<10{deg} and 245<l<365{deg}; it is the Galactic counterpart to the SUMSS (Cat. VIII/81) which covers the southern sky ({delta}<-30{deg}, |b|>10{deg}). This catalogue (15-Aug-2007) consists of 48850 compact sources, made by fitting elliptical gaussians in the MGPS-2 mosaics to a limiting peak brightness of 10mJy/beam. We used a custom method (described in the associated publication) to remove extended sources from the catalogue. Positions in the catalogue are accurate to 1-2". See http://www.astrop.physics.usyd.edu.au/mosaics for access to the mosaic images.
1188. Nearby massive early-type galaxies from MATLAS
ID:
ivo://CDS.VizieR/J/MNRAS/498/2138
Title:
Nearby massive early-type galaxies from MATLAS
Short Name:
J/MNRAS/498/2138
Date:
12 Jan 2022 05:42:10
Publisher:
CDS
Description:
The morphology of galaxies gives essential constraints on the models of galaxy evolution. The morphology of the features in the low-surface-brightness (LSB) regions of galaxies has not been fully explored yet because of observational difficulties. Here we present the results of our visual inspections of very deep images of a large volume-limited sample of 177 nearby massive early-type galaxies from the MATLAS survey. The images reach a surface-brightness limit of 28.5-29mag/arcsec^2^ in the g' band. Using a dedicated navigation tool and questionnaire, we looked for structures at the outskirts of the galaxies such as tidal shells, streams, tails, disturbed outer isophotes, or peripheral star-forming discs, and simultaneously noted the presence of contaminating sources, such as Galactic cirrus. We also inspected internal substructures such as bars and dust lanes. We discuss the reliability of this visual classification investigating the variety of answers made by the participants. We present the incidence of these structures and the trends of the incidence with the mass of the host galaxy and the density of its environment. We find an incidence of shells, stream, and tails of approximately 15%, about the same for each category. For galaxies with masses over 10^11^M_{sun}_, the incidence of shells and streams increases about 1.7 times. We also note a strong unexpected anticorrelation of the incidence of Galactic cirrus with the environment density of the target galaxy. Correlations with other properties of the galaxies, and comparisons to model predictions, will be presented in future papers.
1189. Nearby supernova rates
ID:
ivo://CDS.VizieR/J/MNRAS/412/1419
Title:
Nearby supernova rates
Short Name:
J/MNRAS/412/1419
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is the first paper of a series in which we present new measurements of the observed rates of supernovae (SNe) in the local Universe, determined from the Lick Observatory Supernova Search. We have obtained 2.3 million observations of 14 882 sample galaxies over an interval of 11 years (1998 March to 2008 December). We considered 1036 SNe detected in our sample and used an optimal subsample of 726 SNe (274 Type Ia SNe, 116 Type Ibc SNe and Type II 324 SNe) to determine our SN rates. This is the largest and most homogeneous set of nearby SNe ever assembled for this purpose, and ours is the first local SN rate analysis based on CCD imaging and modern image-subtraction techniques. In this paper, we lay the foundation of the study.
1190. Near-Earth Asteriod Tracking System Archive
ID:
ivo://nasa.heasarc/skyview/neat
Title:
Near-Earth Asteriod Tracking System Archive
Short Name:
NEAT
Date:
29 Apr 2022
Publisher:
NASA/GSFC HEASARC
Description:
The NEAT/SkyMorph survey provides access to the archives of the Near Earth Asteroid Tracking (NEAT) project. NEAT is designed to look for potentially hazardous asteroids, i.e., those whose orbits cross the Earth's. Over 200,000 images are available in the NEAT archive. <a href=https://skyview.gsfc.nasa.gov/skymorph/skymorph.html>SkyMorph</a> provides a Web interface to the NEAT images and allows users to select all images in which a given fixed or moving object is found. <p> Unlike most <i>SkyView</i> surveys, the NEAT data are extremely irregular in their spatial distribution. <i>SkyView</i>'s algorithms for mosaicking images together to form large images are not adequate for the NEAT data, so mosaicking is surpressed. Only data within a single NEAT image will be displayed. The system attempts to find the most recent image within which has a offset in both RA and Dec of less than 0.8 degrees. If no such image is found, then an image with the minimum offset is returned, or the search may fail altogether if there are no nearby plates. The NEAT telescope uses an array of 4 CCDs. The backgrounds of the CCDs may differ significantly. <p> The NEAT survey covers approximately 30% of the sky. Extreme southern and low-Galactic latitude regions are unsurveyed. Coverage is otherwise particularly dense in the ecliptic plane. <p> NEAT data consists primarily of groups of three images taken with separations of 20 minutes and almost identical positions. <i> SkyView </i> will normally return the last of a 'triplet'. The SkyMorph site can be used to display an overlay of triplets to look for targets which moved during the interval between images. <p> A catalog of objects detected in the NEAT/SkyMorph pages is accessible through the SkyMorph pages. 'Light-curves' from all images during which an object was in the NEAT field of view can also be generated. <P> The NEAT data values are in arbitrary density units. To enhance the display data are transformed such that all pixels below the median values are scaled linearly to values 0-20, while all pixels above the median are shifted (but not scaled) to values greater than 20.