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1301. Polarized NVSS sources SEDs
ID:
ivo://CDS.VizieR/J/ApJS/212/15
Title:
Polarized NVSS sources SEDs
Short Name:
J/ApJS/212/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
An understanding of cosmic magnetism requires converting the polarization properties of extragalactic radio sources into the rest-frame in which the corresponding polarized emission or Faraday rotation is produced. Motivated by this requirement, we present a catalog of multiwavelength linear polarization and total intensity radio data for polarized sources from the NRAO VLA Sky Survey. We cross-match these sources with a number of complementary measurements --combining data from major radio polarization and total intensity surveys such as AT20G, B3-VLA, GB6, NORTH6CM, Texas, and WENSS, together with other polarization data published over the last 50 years. For 951 sources, we present spectral energy distributions (SEDs) in both fractional polarization and total intensity, each containing between 3 and 56 independent measurements from 400MHz to 100GHz. We physically model these SEDs, and where available provide the redshift of the optical counterpart. For a superset of 25649 sources we provide the total intensity spectral index, {alpha}. Objects with steep versus flat {alpha} generally have different polarization SEDs: steep-spectrum sources exhibit depolarization, while flat-spectrum sources maintain constant polarized fractions over large ranges in wavelength. This suggests the run of polarized fraction with wavelength is predominantly affected by the local source environment, rather than by unrelated foreground magnetoionic material. In addition, a significant fraction (21%) of sources exhibit "repolarization," which further suggests that polarized SEDs are affected by different emitting regions within the source, rather than by a particular depolarization law. This has implications for the physical interpretation of future broadband polarimetric surveys.
1302. Positions of high-redshift luminous quasars
ID:
ivo://CDS.VizieR/VII/149
Title:
Positions of high-redshift luminous quasars
Short Name:
VII/149
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present finding charts and J2000 positions accurate to ~1" for the 528 high-redshift (z>1), luminous (M_v_<-25.5) quasars investigated in the Hubble Space Telescope Snapshot Survey. The information was produced with the Space Telescope Science Institute's Astrometric Support Program.
1303. POSS Plate Data
ID:
ivo://CDS.VizieR/VI/25
Title:
POSS Plate Data
Short Name:
VI/25
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains plate-center and observational data for all plates of the National Geographic Society and Palomar Observatory Sky Survey (POSS) and its Whiteoak Extension. The POSS proper consists of photographic reproductions of red-sensitive (Kodak 103a-E) and blue-sensitive (Kodak 103a-O) plates taken of 937 different fields with the 48-inch Palomar Schmidt telescope, covering the entire sky above -33 degrees declination. This southern limit was extended to about -45 degrees by J.B. Whiteoak using the same instrument for a series of 100 photographs that have come to be known as the Whiteoak Extension; thus, the survey as a whole includes 1037 fields. This version of the catalogue consists of plate information reproduced from the Catalogue of Plates and plate information on the Whiteoak Extension derived from file headers of the SAOPSS II tape (Lund and Dixon 1973). The fields of the catalog are POSS number, modified Luyten-Palomar (MLP) number, equatorial coordinates of the plate center (B1950), limits of the right ascension on the plate in radians, galactic coordinate of the plate center, number of SAO stars on the plate, observing dates and times, the hour angles for the observations, length of exposure, and seeing rating. The following basic quantities were taken directly from the Catalogue of Plates: POSS number, exposure dates and times, hour angles, seeing ratings, and coordinates in sexagesimal units. The following derived quantities were calculated at the ADC: MLP number, equatorial coordinates in radians, right ascension limits, galactic coordinates, and number of SAO stars.
1304. PPMX Catalog of positions and proper motions
ID:
ivo://CDS.VizieR/I/312
Title:
PPMX Catalog of positions and proper motions
Short Name:
I/312
Date:
21 Oct 2021
Publisher:
CDS
Description:
PPM-Extended (PPMX) is a catalogue of 18,088,919 stars containing astrometric and photometric information. Its limiting magnitude is about 15.2 in the GSC photometric system. PPMX consists of three parts: a) a survey complete down to R_U_=12.8 in the magnitude system of UCAC2; b) additional stars of high-precision proper motions, and c) all other stars from GSC 1.2 identified in 2MASS. The typical accuracy of the proper motions is 2mas/y for 66 percent of the survey stars (a) and the high-precision stars (b), and about 10mas/y for all other stars. PPMX contains photometric information from ASCC-2.5 and 2MASS.
1305. Primordial circumstellar disks in binary systems
ID:
ivo://CDS.VizieR/J/ApJ/696/L84
Title:
Primordial circumstellar disks in binary systems
Short Name:
J/ApJ/696/L84
Date:
21 Oct 2021
Publisher:
CDS
Description:
We combine the results from several multiplicity surveys of pre-main-sequence stars located in four nearby star-forming regions with Spitzer data from three different Legacy Projects. This allows us to construct a sample of 349 targets, including 125 binaries, which we use to to investigate the effect of companions on the evolution of circumstellar disks. We find that the distribution of projected separations of systems with Spitzer excesses is significantly different (P~2.4e-5, according to the K-S test for binaries with separations less than 400AU) from that of systems lacking evidence for a disk. As expected, systems with projected separations less than 40AU are half as likely to retain at least one disk than are systems with projected separations in the 40-400AU range. These results represent the first statistically significant evidence for a correlation between binary separation and the presence of an inner disk (r~1AU). Several factors (e.g., the incompleteness of the census of close binaries, the use of unresolved disk indicators, and projection effects) have previously masked this correlation in smaller samples. We discuss the implications of our findings for circumstellar disk lifetimes and the formation of planets in multiple systems.
1306. Proper motions of Galactic Planetary Nebulae
ID:
ivo://CDS.VizieR/J/A+A/479/155
Title:
Proper motions of Galactic Planetary Nebulae
Short Name:
J/A+A/479/155
Date:
21 Oct 2021
Publisher:
CDS
Description:
More than 1500 Galactic planetary nebulae (PNe) are known but only a tiny fraction of them have measured proper motions. To date, the largest set of proper motion (PM) data for PNe is the one by Cudworth (1974AJ.....79.1384C), which includes 62 objects 25 of which have PM with significance better than 3{sigma}. With our new compilation of 234 PNe we enlarge - compared to Cudworth's 25 - by almost an order of magnitude the number of PNe and central stars (CSs) with reliably measured proper motion (i.e. with significance better than 3{sigma} in at least one component) and confirm some previous measurements. We have used all-sky astrometric catalogues available via the Vizier database to collect proper motion information for a sample of objects selected from the catalogue of PNe positions of Kerber et al. (2003, Cat. <J/A+A/408/1029>).
1307. Proper motion stars survey. XII.
ID:
ivo://CDS.VizieR/J/AJ/107/2240
Title:
Proper motion stars survey. XII.
Short Name:
J/AJ/107/2240
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report new photometry and radial velocities for almost 500 stars from the Lowell Proper Motion Catalog. We combine these results with our prior sample and rederive stellar temperatures based on the photometry, reddening, metallicities (using Chi^2 matching of our 22,500 low S/N high resolution echelle spectra with a grid of synthetic spectra), distances, space motions, and Galactic orbital parameters for 1269 (kinematics) and 1261 (metallicity) of the 1464 stars in the complete survey. The frequency of spectroscopic binaries for the metal-poor ([m/H]<=-1.2) stars with periods shorter than 3000 days is at least 15%. The spectroscopic binary frequency for metal-rich stars ([m/H]>-0.5) appears to be lower, about 9%, but this may be a selection effect. We also discuss special classes of stars, including treatment of the double-lined spectroscopic binaries, and identification of subgiants. Four possible new members of the class of field blue stragglers are noted. We point out the detection of three possible new white dwarfs, six broad-lined (binary) systems, and discuss briefly the three already known nitrogen-rich halo dwarfs.
1308. Properties of late M-dwarfs
ID:
ivo://CDS.VizieR/J/ApJ/789/102
Title:
Properties of late M-dwarfs
Short Name:
J/ApJ/789/102
Date:
21 Oct 2021
Publisher:
CDS
Description:
The distribution of multiplicity among low-mass stars is a key issue to understanding the formation of stars and brown dwarfs, and recent surveys have yielded large enough samples of nearby low-mass stars to study this issue statistically to good accuracy. Previously, we have presented a multiplicity study of ~700 early/mid M-type stars observed with the AstraLux high-resolution Lucky Imaging cameras. Here, we extend the study of multiplicity in M-type stars through studying 286 nearby mid/late M-type stars, bridging the gap between our previous study and multiplicity studies of brown dwarfs. Most of the targets have been observed more than once, allowing us to assess common proper motion to confirm companionship. We detect 68 confirmed or probable companions in 66 systems, of which 41 were previously undiscovered. Detections are made down to the resolution limit of ~100 mas of the instrument. The raw multiplicity in the AstraLux sensitivity range is 17.9%, leading to a total multiplicity fraction of 21%-27% depending on the mass ratio distribution, which is consistent with being flat down to mass ratios of ~0.4, but cannot be stringently constrained below this value. The semi-major axis distribution is well represented by a log-normal function with {mu}_a_= 0.78 and {sigma}_a_= 0.47, which is narrower and peaked at smaller separations than for a Sun-like sample. This is consistent with a steady decrease in average semi-major axis from the highest-mass binary stars to the brown dwarf binaries.
1309. Properties of SDSS QSOs in the ChaMP
ID:
ivo://CDS.VizieR/J/ApJ/690/644
Title:
Properties of SDSS QSOs in the ChaMP
Short Name:
J/ApJ/690/644
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the spectral energy distributions and evolution of a large sample of optically selected quasars from the Sloan Digital Sky Survey that were observed in 323 Chandra images analyzed by the Chandra Multiwavelength Project. Our highest-confidence matched sample includes 1135 X-ray detected quasars in the redshift range 0.2<z<5.4, representing some 36Msec of effective exposure. We provide catalogs of QSO properties, and describe our novel method of calculating X-ray flux upper limits and effective sky coverage. Spectroscopic redshifts are available for about 1/3 of the detected sample; elsewhere, redshifts are estimated photometrically. We detect 56 QSOs with redshift z>3, substantially expanding the known sample. We find no evidence for evolution out to z~5 for either the X-ray photon index {Gamma} or for the ratio of optical/UV to X-ray flux {alpha}_ox_.
1310. Properties of 102 SNe and their 100 hosts
ID:
ivo://CDS.VizieR/J/MNRAS/471/1390
Title:
Properties of 102 SNe and their 100 hosts
Short Name:
J/MNRAS/471/1390
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of the height distributions of the different types of supernovae (SNe) from the plane of their host galaxies. We use a well-defined sample of 102 nearby SNe appearing inside high-inclined (i>=85{deg}), morphologically non-disturbed S0-Sd host galaxies from the Sloan Digital Sky Survey. For the first time, we show that in all the subsamples of spirals, the vertical distribution of core-collapse (CC) SNe is about twice closer to the plane of the host disc than the distribution of SNe Ia. In Sb-Sc hosts, the exponential scale height of CC SNe is consistent with those of the younger stellar population in the Milky Way (MW) thin disc, while the scale height of SNe Ia is consistent with those of the old population in the MW thick disc. We show that the ratio of scale lengths to scale heights of the distribution of CC SNe is consistent with those of the resolved young stars with ages from ~10 up to ~100Myr in nearby edge-on galaxies and the unresolved stellar population of extragalactic thin discs. The corresponding ratio for SNe Ia is consistent with the same ratios of the two populations of resolved stars with ages from a few 100Myr up to a few Gyr and from a few Gyr up to ~10Gyr, as well as with the unresolved population of the thick disc. These results can be explained considering the age-scale height relation of the distribution of stellar population and the mean age difference between Type Ia and CC SNe progenitors.