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2141. Catalog of dense cores in Aquila from Herschel
ID:
ivo://CDS.VizieR/J/A+A/584/A91
Title:
Catalog of dense cores in Aquila from Herschel
Short Name:
J/A+A/584/A91
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present and discuss the results of the Herschel Gould Belt survey (HGBS) observations in an ~11deg^2^ area of the Aquila molecular cloud complex at d~260pc, imaged with the SPIRE and PACS photometric cameras in parallel mode from 70-micron to 500-micron. Using the multi-scale, multi-wavelength source extraction algorithm getsources, we identify a complete sample of starless dense cores and embedded (Class 0-I) protostars in this region, and analyze their global properties and spatial distributions. We find a total of 651 starless cores, ~60% +/-10% of which are gravitationally bound prestellar cores, and they will likely form stars in the future. We also detect 58 protostellar cores. The core mass function (CMF) derived for the large population of prestellar cores is very similar in shape to the stellar initial mass function (IMF), confirming earlier findings on a much stronger statistical basis and supporting the view that there is a close physical link between the stellar IMF and the prestellar CMF. The global shift in mass scale observed between the CMF and the IMF is consistent with a typical star formation efficiency of ~40% at the level of an individual core. By comparing the numbers of starless cores in various density bins to the number of young stellar objects (YSOs), we estimate that the lifetime of prestellar cores is ~1Myr, which is typically ~4 times longer than the core free-fall time, and that it decreases with average core density. We find a strong correlation between the spatial distribution of prestellar cores and the densest filaments observed in the Aquila complex. About 90% of the Herschel-identified prestellar cores are located above a background column density corresponding to A_V_~7, and ~75% of them lie within filamentary structures with supercritical masses per unit length >~16M_{sun}_/pc. These findings support a picture wherein the cores making up the peak of the CMF (and probably responsible for the base of the IMF) result primarily from the gravitational fragmentation of marginally supercritical filaments. Given that filaments appear to dominate the mass budget of dense gas at A_V_>7, our findings also suggest that the physics of prestellar core formation within filaments is responsible for a characteristic "efficiency" SFR/M_dense_~5+/-2x10^-8^yr^-1^ for the star formation process in dense gas.
2142. Catalog of dense cores in Oph molecular cloud
ID:
ivo://CDS.VizieR/J/A+A/638/A74
Title:
Catalog of dense cores in Oph molecular cloud
Short Name:
J/A+A/638/A74
Date:
02 Mar 2022 11:56:27
Publisher:
CDS
Description:
Herschel observations of nearby clouds in the Gould Belt support a paradigm for low-mass star formation, starting with the generation of molecular filaments, followed by filament fragmentation, and the concentration of mass into self-gravitating prestellar cores. With the unique far-infrared and submillimeter continuum imaging capabilities of the Herschel Space observatory, the closeby (d=139pc) Ophiuchus cloud was mapped at five wavelengths from 70 microns to 500 microns with the aim of providing a complete census of dense cores in this region, including unbound starless cores, bound prestellar cores, and protostellar cores. Taking advantage of the high dynamic range and multi-wavelength nature of the Herschel data, we used the multi-scale decomposition algorithms getsources and getfilaments to identify a complete sample of dense cores and filaments in the cloud and study their properties. The densest clouds of the Ophiuchus complex, L1688 and L1689, which thus far are only indirectly described as filamentary regions owing to the spatial distribution of their young stellar objects (YSOs), are confirmed to be dominated by filamentary structures. The tight correlation observed between prestellar cores and filamentary structures in L1688 and L1689 supports the view that solar-type star formation occurs primarily in dense filaments. While the sub clouds of the complex show disparities, L1689 being less efficient than L1688 at forming stars when considering their total mass budgets, both sub clouds share almost the same prestellar core formation efficiency in dense molecular gas. We also find evidence in the Herschel data for a remarkable concentric geometrical configuration in L1688 which is dominated by up to three arc-like compression fronts and presumably created by shockwave events emanating from the Sco OB2 association, including the neighboring massive (O9V) star sigma Sco.
2143. Catalog of dense cores in Oph molecular cloud (Ladjelate+, 2020)
ID:
ivo://CDS.VizieR/J/A+A/438/A74
Title:
Catalog of dense cores in Oph molecular cloud (Ladjelate+, 2020)
Short Name:
J/A+A/438/A74
Date:
16 Jun 2020 07:02:06
Publisher:
CDS
Description:
Based on Herschel Gould Belt survey (Andre et al., 2010A&A...518L.102A) observations of the Ophiuchus Molecular Cloud, and using the multi-scale, multi-wavelength source extraction algorithm getsources (Men'shchikov et al., 2012A&A...542A..81M), we identified a total of 513 dense cores, including 144 starless cores. The observed properties of all dense cores are given in tablea1.dat, and their derived properties are listed in tablea2.dat.
2144. Catalog of dense cores in Orion B from Herschel
ID:
ivo://CDS.VizieR/J/A+A/635/A34
Title:
Catalog of dense cores in Orion B from Herschel
Short Name:
J/A+A/635/A34
Date:
14 Jan 2022 08:07:23
Publisher:
CDS
Description:
We present a detailed study of the Orion B molecular cloud complex (d~400pc), which was imaged with the PACS and SPIRE photometric cameras at wavelengths from 70-micron to 500-micron as part of the Herschel Gould Belt survey (HGBS). We release new high-resolution maps of column density and dust temperature for the whole complex, derived in the same consistent manner as for other HGBS regions. In the filamentary subregions NGC2023 and 2024, NGC2068 and 2071, and L1622, a total of 1768 starless dense cores were identified based on Herschel data, 490-804 (~28-45%) of which are self-gravitating prestellar cores that will likely form stars in the future. A total of 76 protostellar dense cores were also found. The typical lifetime of the prestellar cores was estimated to be t_pre_^OrionB^=1.7(-0.6/+0.8)Myr. The prestellar core mass function (CMF) derived for the whole sample of prestellar cores peaks at ~0.5Msun (in dN/dlogM format) and is consistent with a power-law with logarithmic slope -1.27+/-0.24 at the high-mass end, compared to the Salpeter slope of -1.35. In the Orion B region, we confirm the existence of a transition in prestellar core formation efficiency (CFE) around a fiducial value A_V_^bg^~7mag in background visual extinction, which is similar to the trend observed with Herschel in other regions, such as the Aquila cloud. This is not a sharp threshold, however, but a smooth transition between a regime with very low prestellar CFE at A_V_^bg^<5 and a regime with higher, roughly constant CFE at A_V_^bg^>~10. The total mass in the form of prestellar cores represents only a modest fraction (~20%) of the dense molecular cloud gas above A_V_^bg^>~7mag. About 60-80% of the prestellar cores are closely associated with filaments, and this fraction increases up to >90% when a more complete sample of filamentary structures is considered. Interestingly, the median separation observed between nearest core neighbors corresponds to the typical inner filament width of ~0.1pc, which is commonly observed in nearby molecular clouds, including Orion B. Analysis of the CMF observed as a function of background cloud column density shows that the most massive prestellar cores are spatially segregated in the highest column density areas, and suggests that both higher- and lower-mass prestellar cores may form in denser filaments.
2145. Catalog of distances to molecular clouds
ID:
ivo://CDS.VizieR/J/ApJ/786/29
Title:
Catalog of distances to molecular clouds
Short Name:
J/ApJ/786/29
Date:
21 Oct 2021
Publisher:
CDS
Description:
Distance measurements to molecular clouds are important but are often made separately for each cloud of interest, employing very different data and techniques. We present a large, homogeneous catalog of distances to molecular clouds, most of which are of unprecedented accuracy. We determine distances using optical photometry of stars along lines of sight toward these clouds, obtained from PanSTARRS-1. We simultaneously infer the reddenings and distances to these stars, tracking the full probability distribution function using a technique presented in Green et al. (2014ApJ...783..114G). We fit these star-by-star measurements using a simple dust screen model to find the distance to each cloud. We thus estimate the distances to almost all of the clouds in the Magnani et al. (1985ApJ...295..402M, MBM) catalog, as well as many other well-studied clouds, including Orion, Perseus, Taurus, Cepheus, Polaris, California, and Monoceros R2, avoiding only the inner Galaxy. Typical statistical uncertainties in the distances are 5%, though the systematic uncertainty stemming from the quality of our stellar models is about 10%. The resulting catalog is the largest catalog of accurate, directly measured distances to molecular clouds. Our distance estimates are generally consistent with available distance estimates from the literature, though in some cases the literature estimates are off by a factor of more than two.
2146. Catalog of distant compact groups of galaxies
ID:
ivo://CDS.VizieR/J/AJ/130/425
Title:
Catalog of distant compact groups of galaxies
Short Name:
J/AJ/130/425
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper we present an objectively defined catalog of 459 small, high-density groups of galaxies out to z~0.2 in a region of ~6260deg^2^ in the northern sky derived from the Digitized Second Palomar Observatory Sky Survey. Our catalog extends down to r=19.0 and has a median redshift of z_med_=0.12, making it complementary to Hickson's catalog (Cat. <VII/213>) for the nearby universe (z_med_=0.03).
2147. Catalog of distant galaxy clusters
ID:
ivo://CDS.VizieR/J/ApJ/306/30
Title:
Catalog of distant galaxy clusters
Short Name:
J/ApJ/306/30
Date:
21 Oct 2021
Publisher:
CDS
Description:
A photographic survey for faint galaxies has been carried out with fine-grained photographic emulsions using the 1.2m Schmidt and 5m Hale telescopes, as well as the 4m Mayall telescope. A total of 418 clusters have been found with redshifts mostly in the range from 0.15 to 0.92. The survey was planned to minimize distance-dependent selection effects in the resulting catalog. In areas of sky where the deepest search was made, the sample is complete to about z=0.50; there are 11 clusters per square degree at this limit. At a redshift of 1.0 there should be 63 or 45 clusters per square degree depending on whether q_0_ is 0.0 or 0.5, provided there is no evolution.
2148. Catalog of DMS-type eclipsing binaries
ID:
ivo://CDS.VizieR/V/121
Title:
Catalog of DMS-type eclipsing binaries
Short Name:
V/121
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalogue contains information about 113 detached main-sequence (DMS) type detached binaries with known photometric and geometric elements.
2149. Catalog of double nucleus disk galaxies
ID:
ivo://CDS.VizieR/J/AJ/128/62
Title:
Catalog of double nucleus disk galaxies
Short Name:
J/AJ/128/62
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have compiled a catalog of disk galaxies that have a double nucleus, through systematic examination of existing catalogs and publications. The Catalog of Double Nucleus Disk Galaxies includes 107 objects, together with their basic data. The aim of the catalog is to provide a more systematic and homogeneous basis for the study of the relevance of galaxy interactions and minor mergers in the formation of these double nuclei. We have also investigated possible correlations between geometric and photometric parameters of the double nuclei and their host galaxies. The preliminary results indicate the presence of several significant correlations that should be considered in any theoretical scenario describing minor mergers and disk galaxy evolution
2150. Catalog of early-type contact binaries
ID:
ivo://CDS.VizieR/V/120
Title:
Catalog of early-type contact binaries
Short Name:
V/120
Date:
21 Oct 2021
Publisher:
CDS
Description:
For the first time the early type contact systems were identified as an individual class in M.A. Svechnikov's Catalogue [1] in 1969, which contains 8 systems of this type. The Catalogue of Coch R.H., Plavec M. and Wood F.B. [2] contains 37 systems of the early spectral type. According to Svechnikov's classification [3] a primary component (more massive and hotter) of a CE-system (contact system of early spectral class) has a spectral class earlier than F0-F2 and an orbital period of more than 0.5 day. Usually the spectral class of a primary is earlier than the spectral class of a secondary. Both components fill their Roche-lobes on 90-100%. The following Catalogue of Svechnikov M.A. and Bessonova L.A. [4] contains 38 CE-systems. In 1986 Bondarenko I.I. [5] published the Catalogue of the CE-stars, which contained 83 systems. Physical characteristics of the CE-stars presented in the list of catalogues abovementioned, were obtained by different authors by using different methods of calculation. We propose the Catalogue of the CE-systems with homogeneous absolute physical characteristics, that allows to define accurately general features of this class of binary stars. The comparing of physical characteristics of the CE-systems with other classes` characteristics of binary stars can show the possible evolutionary stages of the CE-systems. The foundation of absolute elements of the CE-systems are the photometric observations (on the whole, the latest multicolour photoelectric, in a few cases photographic and visual observations). The accuracy of modern photometric observations is high, and generally they are processed with the help of reliable computer methods both classical and synthetical methods). But reliable spectral observations (the ray speed curves) are very scarce, especially for both components). We have preferred the spectral class of a primary (usually it is more bright), supposing, that it's spectral class was defined accurately, and photometric and geometrical elements from light curves. All stars from our Catalogue were classified preliminarily as CE-stars by Svechnikov M.A., Istomin L.F. and Grehova O.A. [6]. We have supposed both components fill their Roche-lobes and by using the diagram (q-r[critical]) of Plavec-Kratochvile [7] mass ratio was obtained. The absolute elements were obtained by the approximated method of Svechnikov, which was modernized for CE-stars. Our Catalogue consist of three parts: photometric, geometrical and absolute elements of CE-systems. All stars were divided approximately into two groups: massive (m1>3 solar masses for primary) and less-massive stars (m1<3 solar masses for primary). A Catalogue has a Supplement.

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