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121. Catalog of high extinction clouds
ID:
ivo://CDS.VizieR/J/A+A/515/A42
Title:
Catalog of high extinction clouds
Short Name:
J/A+A/515/A42
Date:
21 Oct 2021
Publisher:
CDS
Description:
The earliest phases of massive star formation are found in cold and dense infrared dark clouds (IRDCs). Since the detection method of IRDCs is very sensitive to the local properties of the background emission, we present here an alternative method to search for high column density in the Galactic plane by using infrared extinction maps. We find clouds between 1 and 5kpc, of which many were missed by previous surveys. By studying the physical conditions of a subsample of these clouds, we aim at a better understanding of the initial conditions of massive star formation. We made extinction maps of the Galactic plane based on the 3.6-4.5 microns color excess between the two shortest wavelength Spitzer IRAC bands, reaching to visual extinctions of ~100mag and column densities of 9x10^22^cm^-2^. From this we compiled a new sample of cold and compact high extinction clouds. We used the MAMBO array at the IRAM 30m telescope to study the morphology, masses, and densities of the clouds and the dense clumps within them. The latter were followed up by pointed ammonia observations with the 100m Effelsberg telescope to determine rotational temperatures and kinematic distances. Extinction maps of the Galactic plane trace large scale structures such as the spiral arms. The extinction method probes lower column densities, N(H_2)~4x10^22^cm^-2^, than the 1.2mm continuum, which reaches up to N(H_2)~3x10^23^cm^-2^ but is less sensitive to large scale structures. The 1.2mm emission maps reveal that the high extinction clouds contain extended cold dust emission, from filamentary structures to still diffuse clouds. Most of the clouds are dark in 24 microns, but several show already signs of star formation via maser emission or bright infrared sources, suggesting that the high extinction clouds contain a variety of evolutionary stages. The observations suggest an evolutionary scheme from dark, cold and diffuse clouds, to clouds with a stronger 1.2mm peak and to finally clouds with many strong 1.2mm peaks, which are also warmer, more turbulent, and already have some star formation signposts.
122. Catalog of Infrared Dark Clouds
ID:
ivo://CDS.VizieR/J/PASP/132/E4301
Title:
Catalog of Infrared Dark Clouds
Short Name:
J/PASP/132/E4301
Date:
21 Oct 2021
Publisher:
CDS
Description:
The field of computer vision has greatly matured in the past decade, and many of the methods and techniques can be useful for astronomical applications. One example is in searching large imaging surveys for objects of interest, especially when it is difficult to specify the characteristics of the objects being searched for. We have developed a method using contour finding and convolution neural networks (CNNs) to search for Infrared Dark Clouds (IRDCs) in the Spitzer Galactic plane survey data. IRDCs can vary in size, shape, orientation, and optical depth, and are often located near regions with complex emission from molecular clouds and star formation, which can make the IRDCs difficult to reliably identify. False positives can occur in regions where emission is absent, rather than from a foreground IRDC. The contour finding algorithm we implemented found most closed figures in the mosaic and we developed rules to filter out some of the false positive before allowing the CNNs to analyze them. The method was applied to the Spitzer data in the Galactic plane surveys, and we have constructed a catalog of IRDCs which includes additional parts of the Galactic plane that were not included in earlier surveys.
123. Catalog of Infrared Observations, Edition 5
ID:
ivo://CDS.VizieR/II/225
Title:
Catalog of Infrared Observations, Edition 5
Short Name:
II/225
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Catalog of Infrared Observations and its associated data base comprise a summary of infrared astronomical observations published in the scientific literature from 1965 through 1997 in the wavelength range 1 micrometer - 1 mm. The database contains infrared observational data for sources outside the Solar System, constructed through a search of the most active scientific journals, IR surveys and catalogs. To date, about 6200 journal articles and 10 major survey catalogs have been included in the data base, which contains 374,653 individual observations of about 62,000 different infrared sources. More than 8,000 of these sources are identifiable with visible objects. The bibliographical files link observations in the catalog with the original articles published in the literature. References give the standard information plus full titles. The Index of Infrared Source Positions is ordered alphabetically by source name and can be used to quickly locate sources in the position-ordered catalog. For sources with no published IR source position, a nominal position may have been given based on other sources. Nominal positions are usually the best available, but not necessarily the true IR positions. Nominal position references are indicated in the index.
124. Catalog of Infrared Observations, Edition 4 (CIO)
ID:
ivo://CDS.VizieR/II/216
Title:
Catalog of Infrared Observations, Edition 4 (CIO)
Short Name:
II/216
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Catalog of Infrared Observations and its associated data base comprise a summary of infrared astronomical observations published in the scientific literature from 1965 through 1995 in the wavelength range 1 micrometer - 1 mm. The database contains infrared observational data for sources outside the Solar System, constructed through a search of the most active scientific journals, IR surveys and catalogs. To date, about 6195 journal articles and 10 major survey catalogs have been included in the data base, which contains more than 325,000 individual observations of about 55,000 different infrared sources. More than 8,000 of these sources are identifiable with visible objects. The bibliographical files link observations in the catalog with the original articles published in the literature. References give the standard information plus full titles. The Index of Infrared Source Positions is ordered alphabetically by source name and can be used to quickly locate sources in the position-ordered catalog. For sources with no published IR source position, a nominal position may have been given based on other sources. Nominal positions are usually the best available, but not necessarily the true IR positions. Nominal position references are indicated in the index.
125. Catalog of Positions of IR Stellar Sources (CPIRSS)
ID:
ivo://CDS.VizieR/I/270
Title:
Catalog of Positions of IR Stellar Sources (CPIRSS)
Short Name:
I/270
Date:
21 Oct 2021
Publisher:
CDS
Description:
The U.S. Naval Observatory Catalog of Positions of Infrared Stellar Sources (CPIRSS) was originally compiled in 1994 to provide astrometry at the sub-arcsecond level for many of the point sources in the 1987 version of the IRAS Point Source Catalog (NASA RP-1190). This was accomplished by the identification of IRAS sources with bright optical stars, checked by requiring the color V-[12] (with [12] being a magnitude derived from the IRAS flux) to be consistent with the optical colors or spectral type. Additionally, the K magnitude (2.2 microns) has been estimated. This version, completed in 2001, contains 37,700 stars and includes the Hipparcos and Tycho-2 astrometry and photometry which was unavailable at the time of the original compilation.
126. Catalog of SDSS-DR5/2MASS spectroscopic quasars
ID:
ivo://CDS.VizieR/J/MNRAS/382/412
Title:
Catalog of SDSS-DR5/2MASS spectroscopic quasars
Short Name:
J/MNRAS/382/412
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 13444 SDSS-DR5 spectroscopic quasars which have an 2MASS near-IR counterpart within 5" of their position.
127. Catalog of Star-Forming Regions in the Galaxy
ID:
ivo://CDS.VizieR/V/112A
Title:
Catalog of Star-Forming Regions in the Galaxy
Short Name:
V/112A
Date:
21 Oct 2021
Publisher:
CDS
Description:
This Catalog of Star-Forming Regions in the Galaxy contains coordinates and fluxes of young objects in the radio and infrared, as well as data on the radial velocities of recombination and molecular lines, for more than three thousand star-forming regions. In addition to photometric and kinematic data, we present information on diffuse and reflecting nebulae, dark and molecular clouds, and other objects related to young stars. The catalog consists of two parts. The main catalog lists star-forming regions in order of Galactic longitude and is supplemented by analogous information for star-forming regions in complexes of dark clouds with large angular sizes that are closest to the Sun. In our preliminary study of the catalog data using a formal classification of the star-forming regions, we subdivided these objects into several classes and characterized them as being populated primarily by massive or low-mass stars at early or late stages of the star-formation process. We also distinguish between relatively nearby and distant complexes.
128. Catalog of super star clusters in IRAS 17138-1017
ID:
ivo://CDS.VizieR/J/A+A/639/A28
Title:
Catalog of super star clusters in IRAS 17138-1017
Short Name:
J/A+A/639/A28
Date:
21 Oct 2021
Publisher:
CDS
Description:
Currently, the global characteristics and evolution of super star clusters (SSCs) are not well understood, due to the large distances to their host galaxies. We aim to study the population of SSCs in IRAS 17138-1017, a luminous infrared galaxy (LIRG), in terms of age, extinction, mass, and luminosity distribution. We analyzed imaging data in the near-infrared from the GeMS/GSAOI instrument on the Gemini telescope and generated simulations with the radiative transfer code MontAGN. The extraction of SSCs from the images and their photometry in J, H, and Ks allowed us to derive color-color and color-magnitude diagrams. Comparison with a theoretical stellar evolutionary track gives a first hint into the extinction towards each SSC, as well as their ages, despite some degeneracy between those two quantities. Spectra given by our radiative transfer code MontAGN, which includes dust emission, also provide insightful predictions and comparisons. We detect with a fair degree of confidence 54 SSCs of m_Ks between 16 mag and 21 mag with a median instrumental uncertainty of 0.05 mag. When plotted on a color-color diagram and a color-magnitude diagram, it appears that most of the sources are very much extinct with respect to an intrinsic theoretical evolutionary track. Once de-reddened, the colors point unambiguously to two distinct and very recent starburst episodes at 2.8 and 4.5Myr. While the SSCs in the 4.5Myr starburst are distributed along the spiral arms, the 2.8Myr SSCs are concentrated in the central region. The luminosity and mass functions present a classical power-law behavior, although with shallower slopes than generally observed in LIRGs. Comparison with radiative transfer simulations shows that, especially for the youngest SSCs, the thermal emission by dust is not negligible and could explain the few very red SSCs that could not be de-reddened safely. This effect could lead to a misevaluation of the age of the starburst by at most 1 or 2Myr.
129. Catalog of 24um sources toward Galactic Center
ID:
ivo://CDS.VizieR/J/ApJS/181/227
Title:
Catalog of 24um sources toward Galactic Center
Short Name:
J/ApJS/181/227
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a ~1.5x8{deg}^2^ (220x1195pc^2^) multiband imaging photometer for Spitzer 24um image of the Galactic center (GC) and an accompanying point-source list. This image is the highest spatial resolution (6"~0.25pc) and sensitivity map ever taken across the GC at this wavelength, showing the emission by warm dust in unprecedented detail. Over 120000 point sources are identified in this catalog with signal-to-noise ratios greater than five and flux densities from 0.6mJy to 9Jy.

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