- ID:
- ivo://CDS.VizieR/J/ApJS/123/233
- Title:
- Catalog of Optically selected cores
- Short Name:
- J/ApJS/123/233
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalog of 406 dense cores optically selected by using the STScI Digitized Sky Survey (DSS). In this catalog 306 cores have neither an embedded young stellar object (EYSO) nor a pre-main-sequence (PMS) star, 94 cores have EYSOs (one core has both an EYSO and a PMS star), and six cores have PMS stars only. Our sample of dense cores in the catalog is fairly complete within a category of northern Lynds class 5 and 6 clouds and southern Hartley et al. class A clouds, providing a database useful for the systematic study of dense cores. Most of the cores listed in the catalog have diameters between 0.05 and 0.36 pc with a mean of ~0.24pc. The sizes (~0.33pc in the mean) of cores with EYSOs are found to be usually larger than the sizes (~0.22pc in the mean) of starless cores. The typical mean gas density of the cores is ~7x10^3^cm^-3^. Most of the cores are more likely elongated than spherical (mean aspect ratio: ~2.4). The ratio of the number of cores with EYSOs to the number of starless cores for our sample is about 0.3, suggesting that the typical lifetime of starless cores is 0.3-1.6Myr, about 3 times longer than the duration of the class 0 and class I phases. This lifetime is shorter than expected from models of ambipolar diffusion, by factors of 2-44.
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- ID:
- ivo://CDS.VizieR/J/A+A/383/631
- Title:
- Catalogue of dust clouds in the Galaxy
- Short Name:
- J/A+A/383/631
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The file cdn.dat is an unified dust cloud catalogue of the Galaxy. Considering an initial list of approximately 6500 entries we condensed them into a cross-identified all-sky catalogue containing 5004 dust clouds.
- ID:
- ivo://CDS.VizieR/J/A+A/463/1227
- Title:
- Catalogue of far-infrared loops in the Galaxy
- Short Name:
- J/A+A/463/1227
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An all-sky survey of loop- and arc-like intensity enhancements has been performed in order to investigate the large-scale structure of the diffuse far-infrared emission. We used maps made of 60 and 100um processed IRAS data (Sky Survey Atlas and dust infrared emission maps) to identify large-scale structures: loops, arcs or cavities, in the far-infrared emission in the Galaxy. Distances were attributed to a subsample of loops using associated objects. We identified 462 far-infrared loops, analyzed their individual FIR properties and their distribution. This data forms the Catalogue of Far-Infrared Loops in the Galaxy. We obtained observational estimates of f_in~30% and f_out~5% for the hot gas volume filling factor of the inward and outward Galactic neighbourhood of the Solar System. We obtained a slope of the power law size luminosity function {beta}=1.37 for low Galactic latitudes in the outer Milky Way. Deviations in the celestial distribution of far-infrared loops clearly indicate, that violent events frequently overwrite the structure of the interstellar matter in the inner Galaxy. Our objects trace out the spiral arm structure of the Galaxy in the neighbourhood of the Sun and their distribution clearly suggests that there is an efficient process that can generate loop-like features at high Galactic latitudes. Power law indices of size luminosity distributions suggest, that the structure of the ISM is ruled by supernovae and stellar winds at low Galactic latitudes while it is governed by supersonic turbulence above the Galactic plane.
- ID:
- ivo://CDS.VizieR/J/A+A/426/503
- Title:
- Catalogue of high velocity molecular outflows (Update)
- Short Name:
- J/A+A/426/503
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog is an up-date of Wu et al., 1996, Cat. <J/A+AS/115/283>.
- ID:
- ivo://CDS.VizieR/J/A+A/405/5
- Title:
- Catalogue of ISM content of normal galaxies
- Short Name:
- J/A+A/405/5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled a catalogue of the gas content for a sample of 1916 galaxies, considered to be a fair representation of normality. The definition of a normal galaxy adopted in this work implies that we have purposely excluded from the catalogue galaxies having distorted morphology (such as interaction bridges, tails or lopsidedness) and/or any signature of peculiar kinematics (such as polar rings, counterrotating disks or other decoupled components). In contrast, we have included systems hosting active galactic nuclei (AGN) in the catalogue. This catalogue revises previous compendia on the ISM content of galaxies published by Bregman et al. (1992ApJ...387..484B) and Casoli et al. (1998A&A...331..451C), and compiles data available in the literature from several small samples of galaxies. Masses for warm dust, atomic and molecular gas, as well as X-ray luminosities have been converted to a uniform distance scale taken from the Catalogue of Principal Galaxies (PGC). We have used two different normalization factors to explore the variation of the gas content along the Hubble sequence: the blue luminosity (LB) and the square of linear diameter (D_25_^2^). Our catalogue significantly improves the statistics of previous reference catalogues and can be used in future studies to define a template ISM content for normal galaxies along the Hubble sequence.
- ID:
- ivo://CDS.VizieR/J/ApJS/194/15
- Title:
- CCCP: Carina's diffuse X-ray emission
- Short Name:
- J/ApJS/194/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 1.42deg^2^ mosaic of diffuse X-ray emission in the Great Nebula in Carina from the Chandra X-ray Observatory Advanced CCD Imaging Spectrometer camera. After removing >14000 X-ray point sources from the field, we smooth the remaining unresolved emission, tessellate it into segments of similar apparent surface brightness, and perform X-ray spectral fitting on those tessellates to infer the intrinsic properties of the X-ray-emitting plasma. By modeling faint resolved point sources, we estimate the contribution to the extended X-ray emission from unresolved point sources and show that the vast majority of Carina's unresolved X-ray emission is truly diffuse. Line-like correlated residuals in the X-ray spectral fits suggest that substantial X-ray emission is generated by charge exchange at the interfaces between Carina's hot, rarefied plasma and its many cold neutral pillars, ridges, and clumps.
- ID:
- ivo://CDS.VizieR/J/PASJ/67/90
- Title:
- Central Molecular Zone in H^13^CO^+^
- Short Name:
- J/PASJ/67/90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a high-resolution wide-field imaging observation of the Central Molecular Zone (CMZ) in H^13^CO^+^ J=1-0 and SiO v=0, J=2-1 emission lines using the 45-m telescope at the Nobeyama Radio Observatory in order to depict the high-density molecular gas mass distribution and explore molecular gas affected by interstellar shocks. By using the clumpfind algorithm we identify 114 molecular clumps in the H^13^CO^+^ data cube.
- ID:
- ivo://CDS.VizieR/J/A+A/602/A8
- Title:
- Cepheus E CO, OH and OI spectra
- Short Name:
- J/A+A/602/A8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Protostellar jets and outflows are key features of the star-formation process, and primary processes of the feedback of young stars on the interstellar medium. Understanding the underlying shocks is necessary to explain how jet and outflow systems are launched, and to quantify their chemical and energetic impacts on the surrounding medium. We performed a high-spectral resolution study of the [OI]63um emission in the outflow of the intermediate-mass Class 0 protostar Cep E-mm. The goal is to determine the structure of the outflow, to constrain the chemical conditions in the various components, and to understand the nature of the underlying shocks, thus probing the origin of the mass-loss phenomenon. We present observations of the OI ^3^P_1_ -> ^3^P_2_, OH between ^2^{Pi}_1/2_ J=3/2 and J=1/2 at 1837.8GHz, and CO (16-15) lines with the GREAT receiver onboard SOFIA towards three positions in the Cep E protostellar outflow: Cep E-mm (the driving protostar), Cep E-BI (in the southern lobe), and Cep E-BII (the terminal position in the southern lobe).
- ID:
- ivo://CDS.VizieR/J/ApJS/163/306
- Title:
- Chandra study of the Cep B star-forming region
- Short Name:
- J/ApJS/163/306
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Cepheus B (Cep B) molecular cloud and a portion of the nearby Cep OB3b OB association, one of the most active regions of star formation within 1kpc, have been observed with the ACIS detector on board the Chandra X-Ray Observatory. We detect 431 X-ray sources, of which 89% are confidently identified as clustered premain-sequence (PMS) stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/660/1556
- Title:
- Characterization of dusty debris disks
- Short Name:
- J/ApJ/660/1556
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dusty debris disks around main-sequence stars are signposts for the existence of planetesimals and exoplanets. From cross-correlating Hipparcos stars with the IRAS catalogs, we identify 146 stars within 120pc of Earth that show excess emission at 60um. This search took special precautions to avoid false positives. Our sample is reasonably well distributed from late B to early K-type stars, but it contains very few later type stars. Even though IRAS flew more than 20 years ago and many astronomers have cross-correlated its catalogs with stellar catalogs, we were still able to newly identify debris disks at as many as 33 main-sequence stars; of these, 32 are within 100pc of Earth. The power of an all-sky survey satellite like IRAS is evident when comparing our 33 new debris disks with the total of only 22 dusty debris disk stars first detected with the more sensitive, but pointed, satellite ISO. Our investigation focuses on the mass, dimensions, and evolution of dusty debris disks.
