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1141. 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.
1142. 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.
1143. 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.
1144. 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.
1145. 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.
1146. 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.
1147. Near-infrared survey around PKS 1343-601
ID:
ivo://CDS.VizieR/J/A+A/466/481
Title:
Near-infrared survey around PKS 1343-601
Short Name:
J/A+A/466/481
Date:
21 Oct 2021
Publisher:
CDS
Description:
The highly obscured radio-bright galaxy PKS 1343-601 at Galactic coordinates of (l,b)=(309.7,+1.8) has been suspected to mark the centre of a hitherto unknown cluster in the wider Great Attractor region. As such it presents an ideal region for a search of galaxies in the near-infrared (NIR) and an in-depth study of their colours as a function of extinction. A visual search of a ~30 square-degree area centred on this radio galaxy on images of the NIR DENIS survey (IJK) revealed 83 galaxies (including two AGNs) and 39 possible candidates. Of these, 49 are also listed in the 2MASS Extended Source Catalog 2MASX. Taking the IRAS/DIRBE extinction values (Schlegel et al., 1998ApJ...500..525S) at face value, the absorption in the optical (AB) ranges from ~2mag to over 100mag across the Galactic Plane. Comparing the detections with other systematic surveys, we conclude that this search is highly complete up to the detection limits of the DENIS survey and certainly surpasses any automatic galaxy finding algorithm applied to crowded areas.
1148. Near-IR catalog of novae in VVV survey area
ID:
ivo://CDS.VizieR/J/A+A/554/A123
Title:
Near-IR catalog of novae in VVV survey area
Short Name:
J/A+A/554/A123
Date:
21 Oct 2021
Publisher:
CDS
Description:
Near-infrared data on classical novae contain useful information about the ejected gas mass and the thermal emission by dust formed during eruption, and provide independent methods to classify the objects according to the colour of their progenitors, and the fading rate and features seen after eruption. The VISTA Variables in the Via Lactea survey (VVV) is a near-IR ESO Public Survey mapping the Milky Way bulge and southern plane. Data taken during 2010-2011 covered the entire area in the JHKs bands plus some epochs in Ks-band of the ongoing VVV variability campaign. We used the VVV data to create a near-IR catalogue of the known Galactic novae in the 562 sq. deg. area covered by VVV. We also compiled the information about novae from the variability tables of the VVV variability campaign.
1149. Near-IR survey of Northern PNs
ID:
ivo://CDS.VizieR/J/A+AS/104/169
Title:
Near-IR survey of Northern PNs
Short Name:
J/A+AS/104/169
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
1150. NEOWISE magnitudes for near-Earth objects
ID:
ivo://CDS.VizieR/J/ApJ/792/30
Title:
NEOWISE magnitudes for near-Earth objects
Short Name:
J/ApJ/792/30
Date:
21 Oct 2021
Publisher:
CDS
Description:
NASA's Wide-field Infrared Survey Explorer (WISE) spacecraft has been brought out of hibernation and has resumed surveying the sky at 3.4 and 4.6 {mu}m. The scientific objectives of the NEOWISE reactivation mission are to detect, track, and characterize near-Earth asteroids and comets. The search for minor planets resumed on 2013 December 23, and the first new near-Earth object (NEO) was discovered 6 days later. As an infrared survey, NEOWISE detects asteroids based on their thermal emission and is equally sensitive to high and low albedo objects; consequently, NEOWISE-discovered NEOs tend to be large and dark. Over the course of its three-year mission, NEOWISE will determine radiometrically derived diameters and albedos for ~2000 NEOs and tens of thousands of Main Belt asteroids. The 32 months of hibernation have had no significant effect on the mission's performance. Image quality, sensitivity, photometric and astrometric accuracy, completeness, and the rate of minor planet detections are all essentially unchanged from the prime mission's post-cryogenic phase.