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141. Asteroidal I, J, K in the DENIS Survey
ID:
ivo://CDS.VizieR/J/A+A/423/381
Title:
Asteroidal I, J, K in the DENIS Survey
Short Name:
J/A+A/423/381
Date:
21 Oct 2021
Publisher:
CDS
Description:
I, J, K magnitudes of 767 asteroids (numbered between 1 and 8000) are presented here. These asteroids have been recovered in the DENIS Survey (Deep European Near-Infrared southern sky Survey) on the basis of their predicted ephemerides. The observations were performed with the 1m-telescope at ESO, La Silla (Chile). The limiting magnitudes of the three bands I, J, K centered at 0.8, 1.25 and 2.15 microns are respectively 18.5, 16.5 and 13.5.
142. Asteroid light curves from PTF survey
ID:
ivo://CDS.VizieR/J/AJ/150/75
Title:
Asteroid light curves from PTF survey
Short Name:
J/AJ/150/75
Date:
21 Oct 2021
Publisher:
CDS
Description:
We fit 54296 sparsely sampled asteroid light curves in the Palomar Transient Factory survey to a combined rotation plus phase-function model. Each light curve consists of 20 or more observations acquired in a single opposition. Using 805 asteroids in our sample that have reference periods in the literature, we find that the reliability of our fitted periods is a complicated function of the period, amplitude, apparent magnitude, and other light-curve attributes. Using the 805-asteroid ground-truth sample, we train an automated classifier to estimate (along with manual inspection) the validity of the remaining ~53000 fitted periods. By this method we find that 9033 of our light curves (of ~8300 unique asteroids) have "reliable" periods. Subsequent consideration of asteroids with multiple light-curve fits indicates a 4% contamination in these "reliable" periods. For 3902 light curves with sufficient phase-angle coverage and either a reliable fit period or low amplitude, we examine the distribution of several phase-function parameters, none of which are bimodal though all correlate with the bond albedo and with visible-band colors. Comparing the theoretical maximal spin rate of a fluid body with our amplitude versus spin-rate distribution suggests that, if held together only by self-gravity, most asteroids are in general less dense than ~2g/cm^3^, while C types have a lower limit of between 1 and 2g/cm3. These results are in agreement with previous density estimates. For 5-20km diameters, S types rotate faster and have lower amplitudes than C types. If both populations share the same angular momentum, this may indicate the two types' differing ability to deform under rotational stress. Lastly, we compare our absolute magnitudes (and apparent-magnitude residuals) to those of the Minor Planet Center's nominal (G=0.15, rotation-neglecting) model; our phase-function plus Fourier-series fitting reduces asteroid photometric rms scatter by a factor of ~3.
143. A survey for quasars near quasars - QNQ
ID:
ivo://CDS.VizieR/J/A+A/487/539
Title:
A survey for quasars near quasars - QNQ
Short Name:
J/A+A/487/539
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of our slitless spectroscopic survey for quasars near 18 known high-redshift quasars (QNQ). The three tables list the survey fields (26.2'x33.5'), the newly confirmed quasars and the remaining unconfirmed quasar candidates, respectively. For each confirmed quasar we give the equatorial coordinates, the redshift measured from the follow-up slit spectra, the redshift uncertainty and the Johnson B magnitude with uncertainty. The redshift uncertainty has been determined from the redshift dispersions of several emission lines. For the remaining candidates we list the equatorial coordinates, the approximate V magnitude, the redshift based on the slitless spectrum and our assessment of the redshift confidence.
144. A Survey of HII Regions in M31
ID:
ivo://CDS.VizieR/J/A+AS/31/439
Title:
A Survey of HII Regions in M31
Short Name:
J/A+AS/31/439
Date:
21 Oct 2021
Publisher:
CDS
Description:
An H-alpha survey, using a focal reducer and narrow-band interference filters, has resulted in the detection of nearly a thousand HII regions in M31. The catalog gives their positions, dimensions, and surface brightnesses. The surface brightnesses are on an absolute scale; the photographic measures were calibrated by using photoelectric measures from two different sources. The detection limit reached corresponds to an emission measure of 40cm^-6^pc at a temperature of 10000K.
145. A Survey of Radio H II Regions in the Northern Sky
ID:
ivo://CDS.VizieR/VIII/58
Title:
A Survey of Radio H II Regions in the Northern Sky
Short Name:
VIII/58
Date:
21 Oct 2021
Publisher:
CDS
Description:
Nearly 500 radio continuum sources near the Galactic plane at declinations greater than -37 degrees were examined for radio recombination line emission to see if they might be HII regions. A total of 462 were detected, about half of these for the first time. The data are presented in an extensive table. Among the newly discovered nebulae are several with recombinations lines so narrow that their electron temperature must be less than 4600 K. In one case the line width (in several transitions) is only 11.6 km/s, requiring electron temperatures less than about 2900 K.
146. A survey of stellar families
ID:
ivo://CDS.VizieR/J/ApJS/190/1
Title:
A survey of stellar families
Short Name:
J/ApJS/190/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a comprehensive assessment of companions to solar-type stars. A sample of 454 stars, including the Sun, was selected from the Hipparcos catalog with {pi}>40mas, {sigma}{pi}/{pi}<0.05, 0.5<=B-V<=1.0 (~F6-K3), and constrained by absolute magnitude and color to exclude evolved stars. These criteria are equivalent to selecting all dwarf and subdwarf stars within 25pc with V-band flux between 0.1 and 10 times that of the Sun, giving us a physical basis for the term "solar-type". New observational aspects of this work include surveys for (1) very close companions with long-baseline interferometry at the Center for High Angular Resolution Astronomy Array, (2) close companions with speckle interferometry, and (3) wide proper-motion companions identified by blinking multi-epoch archival images. In addition, we include the results from extensive radial-velocity monitoring programs and evaluate companion information from various catalogs covering many different techniques. The results presented here include four new common proper-motion companions discovered by blinking archival images. Additionally, the spectroscopic data searched reveal five new stellar companions. Our synthesis of results from many methods and sources results in a thorough evaluation of stellar and brown dwarf companions to nearby Sun-like stars. The overall observed fractions of single, double, triple, and higher-order systems are 56%+/-2%, 33%+/-2%, 8%+/-1%, and 3%+/-1%, respectively, counting all confirmed stellar and brown dwarf companions.
147. A 2011-2013 survey of trans-Neptunian objects
ID:
ivo://CDS.VizieR/J/AJ/152/111
Title:
A 2011-2013 survey of trans-Neptunian objects
Short Name:
J/AJ/152/111
Date:
21 Oct 2021
Publisher:
CDS
Description:
The trans-Neptunian objects (TNOs) preserve evidence of planet building processes in their orbital and size distributions. While all populations show steep size distributions for large objects, a relative deficit of Neptunian trojans and scattering objects with diameters of D<100km has been detected. We investigated this deficit with a 32 square degree survey, in which we detected 77 TNOs that are brighter than a limiting r-band magnitude of 24.6. Our plutino sample (18 objects in 3:2 mean-motion resonance with Neptune) shows a deficit of D<100km objects, rejecting a single power-law size distribution at >99% confidence. Combining our survey with the Canada-France Ecliptic Plane Survey, we perform a detailed analysis of the allowable parameters for the plutino size distribution, including knees and divots. We surmise the existence of 9000+/-3000 plutinos with an absolute magnitude of H_r_{<=}8.66 and 37000_-10000_^+12000^ with H_r_{<=}10.0 (95% confidence). Our survey also discovered one temporary Uranian trojan, one temporary Neptunian trojan, and one stable Neptunian trojan, for which we estimate populations of 110_-100_^+500^, 210_-200_^+900^, and 150_-140_^+600^ with H_r_{<=}10.0, respectively. All three populations are thus less numerous than the main belt asteroids (592 asteroids with H_r_{<=}10.0). With such population sizes, the temporary Neptunian trojans cannot be previously stable trojans diffusing out of the resonance now; they must be recently captured Centaurs or scattering objects. As the bias against the detection of objects grows with larger semimajor axes, our discovery of three 3:1 resonators and one 4:1 resonator adds to the growing evidence that the high-order resonances are far more populated than is typically predicted.
148. ATCA 18GHz pilot survey first results
ID:
ivo://CDS.VizieR/J/MNRAS/354/305
Title:
ATCA 18GHz pilot survey first results
Short Name:
J/MNRAS/354/305
Date:
21 Oct 2021
Publisher:
CDS
Description:
As a pilot study for the first all-sky radio survey at short wavelengths, we have observed 1216deg^2^ of the southern sky at 18GHz (16mm) using a novel wide-band (3.4-GHz bandwidth) analogue correlator on one baseline of the Australia Telescope Compact Array. We scanned a region of sky between declination -71{deg} and -59{deg} with an rms noise level of 15mJy. Follow-up radio imaging of candidate sources above a 4{sigma} detection limit of 60mJy resulted in 221 confirmed detections, for which we have measured accurate positions and flux densities. For extragalactic sources, the survey is roughly 70 per cent complete at a flux density of 126mJy and 95 per cent complete above 300mJy. Almost half the detected sources lie within a few degrees of the Galactic plane, but there are 123 sources with |b|>5{deg}, which can be assumed to be extragalactic.
149. ATESP 5 GHz radio survey. IV.
ID:
ivo://CDS.VizieR/J/A+A/621/A19
Title:
ATESP 5 GHz radio survey. IV.
Short Name:
J/A+A/621/A19
Date:
21 Oct 2021
Publisher:
CDS
Description:
It is now established that the faint radio population is a mixture of star-forming galaxies and faint active galactic nuclei (AGNs), with the former dominating below S_1.4GHz_~100uJy and the latter at larger flux densities. The faint radio AGN component can itself be separated into two main classes, mainly based on the host-galaxy properties: sources associated with red/early-type galaxies (like radio galaxies) are the dominant class down to ~100uJy; quasar/Seyfert-like sources contribute an additional 10-20%. One of the major open questions regarding faint radio AGNs is the physical process responsible for their radio emission. This work aims at investigating this issue, with particular respect to the AGN component associated with red/early-type galaxies. Such AGNs show, on average, flatter radio spectra than radio galaxies and are mostly compact (<=30kpc in size). Various scenarios have been proposed to explain their radio emission. For instance they could be core/core-jet dominated radio galaxies, low-power BL LACs, or advection dominated accretion flow (ADAF) systems. We used the Australia Telescope Compact Array (ATCA) to extend a previous follow-up multi-frequency campaign to 38 and 94GHz. This campaign focuses on a sample of 28 faint radio sources associated with early-type galaxies extracted from the ATESP 5GHz survey. Such data, together with those already at hand, are used to perform radio spectral and variability analyses. Both analyses can help us to disentangle between core- and jet-dominated sources, as well as to verify the presence of ADAF/ADAF+jet systems. Additional high-resolution observations at 38GHz were carried out to characterise the radio morphology of these sources on kiloparsec scales. Most of the sources (25/28) were detected at 38GHz, while only one (ATESP5J224547-400324) of the twelve sources observed at 94 GHz was detected. From the analysis of the radio spectra we confirmed our previous findings that pure ADAF models can be ruled out. Only eight out of the 28 sources were detected in the 38-GHz high-resolution (0.6 arcsec) radio images and of those eight only one showed a tentative core-jet structure. Putting together spectral, variability, luminosity, and linear size information we conclude that different kinds of sources compose our AGN sample: (a) luminous and large (>=100kpc) classical radio galaxies (~18% of the sample); (b) compact (confined within their host galaxies), low-luminosity, power-law (jet-dominated) sources (~46% of the sample); and (c) compact, flat (or peaked) spectrum, presumably core-dominated, radio sources (~36% of the sample). Variability is indeed preferentially associated with the latter.
150. ATESP radio survey. II.
ID:
ivo://CDS.VizieR/VIII/63
Title:
ATESP radio survey. II.
Short Name:
VIII/63
Date:
21 Oct 2021
Publisher:
CDS
Description:
The ATESP survey is a radio survey accomplished with the Australia Telescope Compact Array (ATCA) at 1.4 GHz over a region of 26 square degrees centered at -40 and ranging in RA from 22h30m to 01h15m. The survey consists of 16 radio mosaics with 8x14 arcsec resolution and uniform sensitivity (1 sigma noise = 79 microJy). The final 6 sigmas catalogue contains 2960 sources down to a detection limit of 0.5 mJy. This region is superposed to the redshift survey ESO Slice Project (ESP) and is partly covered by the EIS survey (Patch A; see Cat. J/A+AS/130/323). Table 3 summarizes the main parameters for the final 16 mosaics: for each mosaic are listed the number of fields composing it (columns x rows), the tangent point (sky position used for geometry calculations) and the synthesized beam (size and position angle). The spatial resolution can vary from mosaic to mosaic depending on the particular array (6A, 6C or 6D) used in the observations. The mean value for the synthesized beam is 8"x14". The last three columns of Table 3 show the results of the noise analysis. For each mosaic we report the minimum (negative) flux (S_min) recorded on the image (typically |S_min| is of the order of 0.5 mJy, corresponding to the value at which we have stopped the cleaning) and the noise level. This has been evaluated either as the FWHM of the Gaussian fit to the flux distribution of the pixels (in the range +/-S_min), in order to check for correlated noise (sigma_fit), or as the standard deviation of the average flux in several source-free sub-regions of the mosaics, in order to verify uniformity (<sigma>).

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