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1411. Photometry of VVV CL041 cluster
ID:
ivo://CDS.VizieR/J/A+A/584/A31
Title:
Photometry of VVV CL041 cluster
Short Name:
J/A+A/584/A31
Date:
21 Oct 2021
Publisher:
CDS
Description:
The ESO Public Survey VISTA Variables in the Via Lactea (VVV) provides deep multi-epoch infrared observations for an unprecedented 562 sq. deg of the Galactic bulge and adjacent regions of the disk. Nearly 150 new open clusters and cluster candidates have been discovered in this survey. We present the fourth article in a series of papers focussed on young and massive clusters discovered in the VVV survey. This article is dedicated to the cluster VVV CL041, which contains a new very massive star candidate, WR 62-2. Following the methodology presented in the first paper of the series, wide-field, deep JHKs VVV observations, combined with new infrared spectroscopy, are employed to constrain fundamental parameters (distance, reddening, mass, age) of VVV CL041.
1412. Physical properties of CHIMPS clumps
ID:
ivo://CDS.VizieR/J/A+A/632/A58
Title:
Physical properties of CHIMPS clumps
Short Name:
J/A+A/632/A58
Date:
21 Oct 2021
Publisher:
CDS
Description:
The latest generation of high-angular-resolution unbiased Galactic plane surveys in molecular-gas tracers are enabling the interiors of molecular clouds to be studied across a range of environments. The CO Heterodyne Inner Milky Way Plane Survey (CHIMPS) simultaneously mapped a sector of the inner Galactic plane, within 27.8<l<46.2{deg} and |b|<0.5{deg}, in ^13^CO (3-2) and C^18^O (3-2) at an angular resolution of 15 arcsec. The combination of the CHIMPS data with ^12^CO (3-2) data from the CO High Resolution Survey (COHRS) has enabled us to perform a voxel-by-voxel local-thermodynamic-equilibrium (LTE) analysis, determining the excitation temperature, optical depth, and column density of ^13^CO at each l,b,v position. Distances to discrete sources identified by FellWalker in the ^13^CO (3-2) emission maps were determined, allowing the calculation of numerous physical properties of the sources, and we present the first source catalogues in this paper. We find that, in terms of size and density, the CHIMPS sources represent an intermediate population between large-scale molecular clouds identified by CO and dense clumps seen in thermal dust continuum emission, and therefore represent the bulk transition from the diffuse to the dense phase of molecular gas. We do not find any significant systematic variations in the masses, column densities, virial parameters, mean excitation temperature, or the turbulent pressure over the range of Galactocentric distance probed, but we do find a shallow increase in the mean volume density with increasing Galactocentric distance. We find that inter-arm clumps have significantly narrower linewidths, and lower virial parameters and excitation temperatures than clumps located in spiral arms. When considering the most reliable distance-limited subsamples, the largest variations occur on the clump-to-clump scale, echoing similar recent studies that suggest that the star-forming process is largely insensitive to the Galactic-scale environment, at least within the inner disc.
1413. Physical properties of GRS molecular clouds
ID:
ivo://CDS.VizieR/J/ApJ/723/492
Title:
Physical properties of GRS molecular clouds
Short Name:
J/ApJ/723/492
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive the physical properties of 580 molecular clouds based on their ^12^CO and ^13^CO line emission detected in the University of Massachusetts-Stony Brook (UMSB) and Galactic Ring surveys (GRS). We provide a range of values of the physical properties of molecular clouds, and find a power-law correlation between their radii and masses, suggesting that the fractal dimension of the interstellar medium is around 2.36. This relation, M=(228+/-18)R^2.36+/-0.04^, allows us to derive masses for an additional 170 Galactic Ring Survey (GRS) molecular clouds not covered by the UMSB survey. We derive the Galactic surface mass density of molecular gas and examine its spatial variations throughout the Galaxy. We find that the azimuthally averaged Galactic surface density of molecular gas peaks between Galactocentric radii of 4 and 5kpc. Although the Perseus arm is not detected in molecular gas, the Galactic surface density of molecular gas is enhanced along the positions of the Scutum-Crux and Sagittarius arms.
1414. Physical properties of VVDS galaxies
ID:
ivo://CDS.VizieR/J/A+A/495/53
Title:
Physical properties of VVDS galaxies
Short Name:
J/A+A/495/53
Date:
21 Oct 2021
Publisher:
CDS
Description:
We want to derive the mass-metallicity relation of star-forming galaxies up to z~0.9, using data from the VIMOS VLT Deep Survey. The mass-metallicity relation is commonly understood as the relation between the stellar mass and the gas-phase oxygen abundance. Automatic measurement of emission-line fluxes and equivalent widths have been performed on the full spectroscopic sample of the VIMOS VLT Deep Survey. This sample is divided into two sub-samples depending on the apparent magnitude selection: wide (I_AB_<22.5) and deep (I_AB_<24). These two samples span two different ranges of stellar masses. Emission-line galaxies have been separated into star-forming galaxies and active galactic nuclei using emission line ratios. For the star-forming galaxies the emission line ratios have also been used to estimate gas-phase oxygen abundance, using empirical calibrations renormalized in order to give consistent results at low and high redshifts. The stellar masses have been estimated by fitting the whole spectral energy distributions with a set of stellar population synthesis models.
1415. Pi Ghz Sky Survey (PiGSS). I.
ID:
ivo://CDS.VizieR/J/ApJ/725/1792
Title:
Pi Ghz Sky Survey (PiGSS). I.
Short Name:
J/ApJ/725/1792
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Pi GHz Sky Survey (PiGSS) is a key project of the Allen Telescope Array. PiGSS is a 3.1GHz survey of radio continuum emission in the extragalactic sky with an emphasis on synoptic observations that measure the static and time-variable properties of the sky. During the 2.5 year campaign, PiGSS will twice observe ~250000 radio sources in the 10000deg^2^ region of the sky with b>30{deg} to an rms sensitivity of ~1mJy. Additionally, sub-regions of the sky will be observed multiple times to characterize variability on timescales of days to years. We present here observations of a 10deg^2^ region in the Bootes constellation overlapping the NOAO Deep Wide Field Survey field. The PiGSS image was constructed from 75 daily observations distributed over a 4 month period and has an rms flux density between 200 and 250uJy. This represents a deeper image by a factor of 4-8 than we will achieve over the entire 10000deg^2^. We provide flux densities, source sizes, and spectral indices for the 425 sources detected in the image. We identify ~100 new flat-spectrum radio sources; we project that when completed PiGSS will identify 104 flat-spectrum sources. We identify one source that is a possible transient radio source. This survey provides new limits on faint radio transients and variables with characteristic durations of months.
1416. Pi GHz Sky Survey (PiGSS). II.
ID:
ivo://CDS.VizieR/J/ApJ/739/76
Title:
Pi GHz Sky Survey (PiGSS). II.
Short Name:
J/ApJ/739/76
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from daily radio continuum observations of the Bootes field as part of the Pi GHz Sky Survey (PiGSS). These results are part of a systematic and unbiased campaign to characterize variable and transient sources in the radio sky. The observations include 78 individual epochs distributed over five months at a radio frequency of 3.1GHz with a median rms image noise in each epoch of 2.8mJy. We produce five monthly images with a median rms of 0.6mJy. No transient radio sources are detected in the daily or monthly images. At 15mJy, we set an upper limit (2{sigma}) to the surface density of one-day radio transients at 0.025deg^-2^. At 5mJy, we set an upper limit (2{sigma}) to the surface density of one-month radio transients at 0.18deg^-2^. We also produce light curves for 425 sources and explore the variability properties of these sources. Approximately 20% of the sources exhibit some variability on daily and monthly timescales. The maximum rms fractional modulations on the one-day and one-month timescales for sources brighter than 10mJy are 2 and 0.5, respectively. The probability of a daily fluctuation for all sources and all epochs by a factor of 10 is less than 10^-4^. We compare the radio to mid-infrared variability for sources in the field and find no correlation. Finally, we apply the statistics of transient and variable populations to constrain models for a variety of source classes.
1417. PiGSS. III. ELAIS-N1, Coma & Lockman fields
ID:
ivo://CDS.VizieR/J/ApJ/762/93
Title:
PiGSS. III. ELAIS-N1, Coma & Lockman fields
Short Name:
J/ApJ/762/93
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from a total of 459 repeated 3.1GHz radio continuum observations (of which 379 were used in a search for transient sources) of the ELAIS-N1, Coma, Lockman Hole, and NOAO Deep Wide Field Survey fields as part of the Pi GHz Sky Survey. The observations were taken approximately once per day between 2009 May and 2011 April. Each image covers 11.8 square degrees and has 100" FWHM resolution. Deep images for each of the four fields have rms noise between 180 and 310{mu}Jy, and the corresponding catalogs contain ~200 sources in each field. Typically 40-50 of these sources are detected in each single-epoch image. This represents one of the shortest cadence, largest area, multi-epoch surveys undertaken at these frequencies. We compare the catalogs generated from the combined images to those from individual epochs, and from monthly averages, as well as to legacy surveys. We undertake a search for transients, with particular emphasis on excluding false positive sources. We find no confirmed transients, defined here as sources that can be shown to have varied by at least a factor of 10. However, we find one source that brightened in a single-epoch image to at least six times the upper limit from the corresponding deep image. We also find a source associated with a z=0.6 quasar which appears to have brightened by a factor ~3 in one of our deep images, when compared to catalogs from legacy surveys. We place new upper limits on the number of transients brighter than 10mJy: fewer than 0.08 transients deg^-2^ with characteristic timescales of months to years; fewer than 0.02deg^-2^ with timescales of months; and fewer than 0.009deg^-2^ with timescales of days. We also plot upper limits as a function of flux density for transients on the same timescales.
1418. Planck Catalog of Compact Sources Release 1
ID:
ivo://CDS.VizieR/VIII/91
Title:
Planck Catalog of Compact Sources Release 1
Short Name:
VIII/91
Date:
21 Oct 2021
Publisher:
CDS
Description:
Planck is a European Space Agency (ESA) mission, with significant contributions from the U.S. National Aeronautics and Space Agency (NASA). It is the third generation of space-based cosmic microwave background experiments, after the Cosmic Background Explorer (COBE) and the Wilkinson Microwave Anisotropy Probe (WMAP). Planck was launched on 14 May 2009 on an Ariane 5 rocket from Kourou, French Guiana. Following a cruise to the Earth-Sun L2 Lagrange point, cooling and in orbit checkout, Planck initiated the First Light Survey on 13 August 2009. Since then, Planck has been continuously measuring the intensity of the sky over a range of frequencies from 30 to 857GHz (wavelengths of 1cm to 350{mu}m) with spatial resolutions ranging from about 33' to 5' respectively. The Low Frequency Instrument (LFI) on Planck provides temperature and polarization information using radiometers which operate between 30 and 70GHz. The High Frequency Instrument (HFI) uses pairs of polarization-sensitive bolometers at each of four frequencies between 100 and 353GHz but does not measure polarization information in the two upper HFI bands at 545 and 857GHz. The lowest frequencies overlap with WMAP, and the highest frequencies extend far into the submillimeter in order to improve separation between Galactic foregrounds and the cosmic microwave background (CMB). By extending to wavelengths longer than those at which the Infrared Astronomical Satellite (IRAS) operated, Planck is providing an unprecedented window into dust emission at far-infrared and submillimeter wavelengths. The PCCS (Planck Catalog of Compact Sources) is the list of sources detected in the first 15 months of Planck "nominal" mission. It consists of nine single-frequency catalogues of compact sources, both Galactic and extragalactic, detected over the entire sky. The PCCS covers the frequency range 30-857 GHz with higher sensitivity (it is 90% complete at 180mJy in the best channel) and better angular resolution than previous all-sky surveys in the microwave band. By construction its reliability is >80% and more than 65% of the sources have been detected at least in two contiguous Planck channels. Many of the Planck PCCS sources can be associated with stars with dust shells, stellar cores, radio galaxies, blazars, infrared luminous galaxies and Galactic interstellar medium features.
1419. Planck Catalogue of Galactic cold clumps (PGCC)
ID:
ivo://CDS.VizieR/J/A+A/594/A28
Title:
Planck Catalogue of Galactic cold clumps (PGCC)
Short Name:
J/A+A/594/A28
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Planck Catalogue of Galactic Cold Clumps (PGCC), an all-sky catalogue of Galactic cold clump candidates detected by Planck. This catalogue is the full version of the Early Cold Core (ECC) catalogue, which was made available in 2011 with the Early Release Compact Source Catalogue (ERCSC) and which contained 915 high signal-to-noise sources. It is based on the Planck 48-month mission data that are currently being released to the astronomical community. The PGCC catalogue is an observational catalogue consisting exclusively of Galactic cold sources. The three highest Planck bands (857, 454, and 353GHz) have been combined with IRAS data at 3THz to perform a multi-frequency detection of sources colder than their local environment. After rejection of possible extragalactic contaminants, the PGCC catalogue contains 13188 Galactic sources spread across the whole sky, i.e., from the Galactic plane to high latitudes, following the spatial distribution of the main molecular cloud complexes. The median temperature of PGCC sources lies between 13 and 14.5K, depending on the quality of the flux density measurements, with a temperature ranging from 5.8 to 20K after removing the sources with the top 1% highest temperature estimates. Using seven independent methods, reliable distance estimates have been obtained for 5574 sources, which allows us to derive their physical properties such as their mass, physical size, mean density, and luminosity. The PGCC sources are located mainly in the solar neighbourhood, but also up to a distance of 10.5kpc in the direction of the Galactic centre, and range from low-mass cores to large molecular clouds. Because of this diversity and because the PGCC catalogue contains sources in very different environments, the catalogue is useful for investigating the evolution from molecular clouds to cores. Finally, it also includes 54 additional sources located in the Small and Large Magellanic Clouds.
1420. Planck Early Release Compact Source Catalogue
ID:
ivo://CDS.VizieR/VIII/88
Title:
Planck Early Release Compact Source Catalogue
Short Name:
VIII/88
Date:
21 Oct 2021
Publisher:
CDS
Description:
Planck is a European Space Agency (ESA) mission, with significant contributions from the U.S. National Aeronautics and Space Agency (NASA). It is the third generation of space-based cosmic microwave background experiments, after the Cosmic Background Explorer (COBE) and the Wilkinson Microwave Anisotropy Probe (WMAP). Planck was launched on 14 May 2009 on an Ariane 5 rocket from Kourou, French Guiana. Following a cruise to the Earth-Sun L2 Lagrange point, cooling and in orbit checkout, Planck initiated the First Light Survey on 13 August 2009. Since then, Planck has been continuously measuring the intensity of the sky over a range of frequencies from 30 to 857GHz (wavelengths of 1cm to 350{mu}m) with spatial resolutions ranging from about 33' to 5' respectively. The Low Frequency Instrument (LFI) on Planck provides temperature and polarization information using radiometers which operate between 30 and 70GHz. The High Frequency Instrument (HFI) uses pairs of polarization-sensitive bolometers at each of four frequencies between 100 and 353GHz but does not measure polarization information in the two upper HFI bands at 545 and 857GHz. The lowest frequencies overlap with WMAP, and the highest frequencies extend far into the submillimeter in order to improve separation between Galactic foregrounds and the cosmic microwave background (CMB). By extending to wavelengths longer than those at which the Infrared Astronomical Satellite (IRAS) operated, Planck is providing an unprecedented window into dust emission at far-infrared and submillimeter wavelengths. The Planck Early Release Compact Source Catalogue (ERCSC) is a list of all high reliability sources, both Galactic and extragalactic, derived from the first sky coverage. The data that went into this early release comprise all observations undertaken between 13 August 2009 and 6 June 2010, corresponding to Planck operational days 91-389. Since the Planck scan strategy results in the entire sky being observed every 6 months, the data considered in this release correspond to more than the first sky coverage. The source lists have reliability goals of >90% across the entire sky and >95% at high Galactic latitude. The goals on photometric accuracy are 30% while the positional accuracy goal translates to a positional root mean square (RMS) uncertainty that is less than 1/5 of the beam full width at half maximum (FWHM). Detailed explanations about the mission and the catalogs included here can be found in the "Explanatory supplement" (file "ercsc4_3.pdf"). Skymaps of the sources can be found in the "skymaps" subdirectory; postage stamps of the sources in the ECC (Early Cold Cores) catalog and in the different filters are located in the "stamps" subdirectory. The "Byte-by-byte Description" below contain column names standardized according to the conventions used at CDS; the original column names, as defined in the FITS files, are listed, enclosed within parentheses, at the end of the explanations.

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