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Auriga-California Molecular Cloud Catalog
The Auriga-California molecular cloud is a large region of relatively modest star formation that is part of the Gould Belt. The "Auriga-California Molecular Cloud" (ACMC) Herschel program observed a 14.5 square degree area in five far-infrared bands.The ACMC catalog provides photometry for the 60 point-like and very compact sources in each band: PACS 70 and 160 microns, SPIRE 250, 350, and 500 microns.
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Milky Way Molecular Clouds from CO Measurements
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This study presents a catalog of 8107 molecular clouds that covers the entire Galactic plane and includes 98% of the 12CO emission observed within b +/- 5 deg. The catalog was produced using a hierarchical cluster identification method applied to the result of a Gaussian decomposition of the Dame+ (2001ApJ...547..792D) data. The total H2 mass in the catalog is 1.2 x 109 Msun, in agreement with previous estimates. The authors find that 30% of the sight lines intersect only a single cloud, with another 25% intersecting only two clouds. The most probable cloud size is R~30pc. In contrast with the general idea, the authors find a rather large range of values of surface densities, Sigma = 2 to 300 Msun/pc2, and a systematic decrease with increasing Galactic radius, Rgal. The cloud velocity dispersion and the normalization sigma0 = sigmav / R1/2 both decrease systematically with Rgal. When studied over the whole Galactic disk, there is a large dispersion in the line width-size relation and a significantly better correlation between sigmav and SigmaR. The normalization of this correlation is constant to better than a factor of two for Rgal < 20kpc. This relation is used to disentangle the ambiguity between near and far kinematic distances. The authors report a strong variation of the turbulent energy injection rate. In the outer Galaxy it may be maintained by accretion through the disk and/or onto the clouds, but neither source can drive the 100 times higher cloud-averaged injection rate in the inner Galaxy. The data set used in this catalog come from that of Dame+ (2001ApJ...547..792D). Those authors combined observations obtained over a period of 20 yr with two telescopes, one in the north (first located in New York City and then moved to Cambridge, Massachusetts) and one in the south (Cerro Tololo, Chile). These 1.2m telescopes have an angular resolution of ~8.5' at 115GHz, the frequency of the 12CO 1-0 line. For the current study the authors used the data set covering the whole Galactic plane with +/- 5 deg in Galactic latitude. This table was created by the HEASARC in March 2019 based upon the CDS Catalog J/ApJ/834/57 file table1.dat. This is a service provided by NASA HEASARC .
Chandra ACIS Survey for X-Ray AGN in Nearby Galaxies
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The authors searched the public archive of the Chandra X-ray Observatory as of 2016 March and assembled a sample of 719 galaxies within 50 Mpc with available Advanced CCD Imaging Spectrometer observations. By cross-correlation with the optical or near-infrared nuclei of these galaxies, 314 of them are identified to have an X-ray active galactic nucleus (AGN). The majority of them are low-luminosity AGNs and are unlikely X-ray binaries based upon their spatial distribution and luminosity functions. The AGN fraction is around 60% for elliptical galaxies and early-type spirals, but drops to roughly 20% for Sc and later types, consistent with previous findings in the optical. However, the X-ray survey is more powerful in finding weak AGNs, especially from regions with active star formation that may mask the optical AGN signature. For example, 31% of the H II nuclei are found to harbor an X-ray AGN. For most objects, a single power-law model subject to interstellar absorption is adequate to fit the spectrum, and the typical photon index is found to be around 1.8. For galaxies with a non-detection, their stacked Chandra image shows an X-ray excess with a luminosity of a few times 1037 erg/s on average around the nuclear region, possibly composed of faint X-ray binaries. This paper reports on the technique and results of the survey; in-depth analysis and discussion of the results were to be reported in forthcoming papers, e.g., She et al. (2017, ApJ, 842, 131). The sample was assembled based on Chandra/ACIS observations that were publicly available as of 2016 March. The authors first generated a full list of ACIS observations, and then searched in the NASA/IPAC Extragalactic Database (NED) for galaxies within 50 Mpc whose nuclear positions were less than 8 arcminutes from the aim point of any Chandra observation. The adopted distances were taken from NED, in the following order of priority: surface brightness fluctuations, Cepheid variables, tip of the red giant branch, Type Ia supernovae, the fundamental plane, Faber-Jackson relation, Tully-Fisher relation. If more than one reference is available for the distance by the same means, the latest one is selected, unless otherwise specified. Whenever possible, the authors obtain positions of the galaxy nuclei based on measurements from near-infrared images, which suffer from less obscuration by dust or confusion from young star-forming regions. Most of the data come from the Two-Micron All Sky Survey (2MASS) extended source catalog (Skrutskie et al. 2006, AJ, 131, 1163), or NED otherwise. In a few cases, the NED positions come from radio observations. The authors discarded galaxies whose nuclear positions in NED were obtained from X-ray observations. This table was created by the HEASARC in September 2017 based upon the CDS Catalog J/ApJ/835/223 files table1.dat, table2.dat and table4.dat. This is a service provided by NASA HEASARC .
LMC 30 Doradus Complex Chandra X-Ray Point Source Catalog
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This table contains the results of a study of the X-ray point-source population of the 30 Doradus (30 Dor) star-forming complex in the Large Magellanic Cloud (LMC) using high spatial-resolution X-ray images and spatially-resolved spectra obtained with the Advanced CCD Imaging Spectrometer (ACIS) on board the Chandra X-Ray Observatory. The observation of ~21 ks was made on 1999 September 21 and placed the cluster R136 at the aim point of the ACIS Imaging Array (ACIS-I). This table lists the the X-ray sources detected in the 17' x 17' field centered on R136, the massive star cluster which lies at the center of the main 30 Dor nebula. 20 of the 32 Wolf-Rayet stars in the ACIS field are detected. The cluster R136 is resolved at the sub-arcsecond level into almost 100 X-ray sources, including many typical O3-O5 stars, as well as a few bright X-ray sources which had been previously reported. Over 2 orders of magnitude of scatter in the X-ray luminosity Lx (calculated assuming a distance of 50 kpc) is seen among R136 O stars, suggesting that X-ray emission in the most massive stars depends critically on the details of wind properties and the binarity of each system, rather than reflecting the widely reported characteristic value Lx/Lbol ~ 10-7. Such a canonical ratio may exist for single massive stars in R136, but these data are too shallow to confirm this relationship. Through this and more recent X-ray studies of 30 Dor, the complete life cycle of a massive stellar cluster can be revealed. This HEASARC table contains both the primary high-significance X-ray sources as well as some lower-significance tentative X-ray sources. The latter sources should not be considered definitive. A subsequent Chandra observation of this field, with several times the exposure of this observation, will result in a longer, more complete list of point sources than that given in this paper. This table was created by the HEASARC in February 2007 based on the merger of electronic versions of Tables 1, 2 and 5 from the above reference which were obtained from the AJ website. It does not include the results from the spectral analysis of 49 of the X-ray sources having a photometric significance (signal-to-noise ratio) greater than 2 which are presented in Tables 3 and 4 of the reference paper. This is a service provided by NASA HEASARC .
Rosette Molecular Cloud Chandra X-Ray Point Source Catalog
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The authors of this study have explored the young stellar populations in the Rosette Molecular Cloud (RMC) region with high spatial resolution X-ray images from the Chandra X-ray Observatory, which are effective in locating weak-lined T Tauri stars as well as disk-bearing young stars. A total of 395 X-ray point sources are detected, 299 of which (76%) have an optical or near-infrared (NIR) counterpart identified from deep FLAMINGOS images. From X-ray and mass sensitivity limits, the authors infer a total population of ~1700 young stars in the survey region. Based on smoothed stellar surface density maps, they investigate the spatial distribution of the X-ray sources and define three distinctive structures and substructures within them. Structures B and C are associated with previously known embedded IR clusters, while structure A is a new X-ray-identified unobscured cluster. A high-mass protostar RMCX 89 = IRAS 06306+0437 and its associated sparse cluster are studied. The different subregions are not coeval but do not show a simple spatial-age pattern. Disk fractions vary between subregions and are generally <~ 20% of the total stellar population inferred from the X-ray survey. The data are consistent with speculations that triggered star formation around the H II region is present in the RMC, but do not support a simple sequential triggering process through the cloud interior. While a significant fraction of young stars are located in a distributed population throughout the RMC region, it is not clear if they originated in clustered environments. This HEASARC table contains the 348 primary sources listed in Table 1 of the reference paper, as well as the 47 tentative sources listed in Table 2 (the latter having a likelihood > 10-3 of being a spurious background fluctuation based on Poisson statistics), to make a total of 395 X-ray sources. The information on optical and infrared counterparts to these X-ray sources which was provided in Table 4 of the reference paper has also been included herein. In order to allow users to clearly identify these 2 samples, the HEASARC has created a parameter source_sample which is set to 'P' for the Table 1 primary sources and to 'T' for the Table 2 tentative sources. This HEASARC table also contains the X-ray spectroscopic information derived for 158 sources which have photometric significance (the snr parameter) >= 2.0 which was presented in Table 3 of the reference paper. All spectral fits used the "wabs(apec)" model in XSPEC and assumed 0.3 * Z_Sun abundances. The quoted emission measures and X-ray luminosities assume a distance to the Rosette molecular cloud of 1.4 kpc. This table was created by the HEASARC in July 2009 based on the merger of electronic versions of tables 1, 2, 3 and 4 from the above reference which were obtained from the ApJ web site. This is a service provided by NASA HEASARC .
HerMES 500 micron StarFinder Catalog
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The Herschel Multi-tiered Extragalactic Survey (HerMES) is a legacy programme (KPGT_soliver1) designed to map a set of nested fields totalling 380 sq. deg. Fields range in size from 0.01 to 20 sq. deg., using SPIRE at 250, 350 and 500 microns. These bands cover the peak of the redshifted thermal spectral energy distribution from interstellar dust and thus capture the reprocessed optical and ultraviolet radiation from star formation that has been absorbed by dust, and are critical for forming a complete multiwavelength understanding of galaxy formation and evolution.
Atacama Cosmology Telescope 2008 Southern Survey 148/218 GHz Source Catalog
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This table contains a catalog of 191 extragalactic sources detected by the Atacama Cosmology Telescope (ACT) at 148 and/or 218 GHz in the 2008 Southern survey. Flux densities span 14 -1700 mJy, and the authors use source spectral indices derived using ACT-only data to divide their sources into two subpopulations: 167 radio galaxies powered by central active galactic nuclei (AGN) and 24 dusty star-forming galaxies (DSFGs). They cross-identify 97% of their sources (166 of the AGN and 19 of the DSFGs) with those in currently available catalogs. When combined with flux densities from the Australia Telescope 20-GHz survey and follow-up observations with the Australia Telescope Compact Array, the synchrotron-dominated population is seen to exhibit a steepening of the slope of the spectral energy distribution from 20 to 148 GHz, with the trend continuing to 218 GHz. The ACT dust-dominated source population has a median spectral index, alpha148-218GHz, of 3.7+0.62-0.86, and includes both local galaxies and sources with redshift around 6. Dusty sources with no counterpart in existing catalogs likely belong to a recently discovered subpopulation of DSFGs lensed by foreground galaxies or galaxy groups. The ACT experiment (Swetz et al., 2011, ApJS, 194, 41) is situated on the slopes of Cerro Toco in the Atacama Desert of Chile at an elevation of 5190m. ACT's latitude gives access to both the northern and southern celestial hemispheres. Observations occurred simultaneously in three frequency bands, at 148 GHz (2.0 mm), 218 GHz (1.4 mm) and 277 GHz (1.1 mm) with angular resolutions of roughly 1.4, 1.0 and 0.9 arcminutes, respectively. The ACT-detected source list contains 169 sources selected at 148 GHz with S/N > 5, spanning two decades in flux density, from 14 to 1700 mJy. The 218 GHz map independently yielded 133 sources with S/N > 5. The combination of these two independent source lists from which the present table was constructed gives a total count of 191 sources, with 110 galaxies detected with S/N > 5 at both frequencies. This table was created by the HEASARC in May 2015 based on CDS Catalog J/MNRAS/439/1556/ file table4.dat. This is a service provided by NASA HEASARC .
HerMES 350 micron StarFinder Catalog
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The Herschel Multi-tiered Extragalactic Survey (HerMES) is a legacy programme (KPGT_soliver1) designed to map a set of nested fields totalling 380 sq. deg. Fields range in size from 0.01 to 20 sq. deg., using SPIRE at 250, 350 and 500 microns. These bands cover the peak of the redshifted thermal spectral energy distribution from interstellar dust and thus capture the reprocessed optical and ultraviolet radiation from star formation that has been absorbed by dust, and are critical for forming a complete multiwavelength understanding of galaxy formation and evolution.
SMC H-Alpha Emission Stars/Nebulae
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This database table contains a list of H-alpha emission-line stars and small nebulae in the Small Magellanic Cloud (SMC) that were discovered in an objective-prism survey. This survey was performed through an H-alpha + [N II] interference filter using the 0.90m Curtis Schmidt telescope at Cerro Tololo Inter-American Observatory (CTIO). 1898 emission-line objects were detected in the main body of the SMC, almost quadrupling the number of those discovered in previous objective-prism surveys of the same region. Among these 1898 objects are newly discovered planetary nebulae, compact H II regions, and late-type stars. Continuum intensities, the shapes and strengths of the H-alpha emission line, co-ordinates and (where available) cross-identifications are provided for the listed objects. This version of the SMC H-alpha Emission-Line Stars and Small Nebulae Catalog of Meyssonnier and Azzopardi was created by the HEASARC in November 1997 based on the ADC/CDS machine-readable catalog J/A+AS/102/451. This is a service provided by NASA HEASARC .
HerMES 250 micron StarFinder Catalog
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The Herschel Multi-tiered Extragalactic Survey (HerMES) is a legacy programme (KPGT_soliver1) designed to map a set of nested fields totalling 380 sq. deg. Fields range in size from 0.01 to 20 sq. deg., using SPIRE at 250, 350 and 500 microns. These bands cover the peak of the redshifted thermal spectral energy distribution from interstellar dust and thus capture the reprocessed optical and ultraviolet radiation from star formation that has been absorbed by dust, and are critical for forming a complete multiwavelength understanding of galaxy formation and evolution.
Small Magellanic Cloud Deep Fields X-Ray Point Source Catalog
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This table contains the results of a pair of 100 ks Chandra observations of the Small Magellanic Cloud (SMC) to survey high-mass X-ray binaries (HMXBs), stars, and low-mass X-ray binaries (LMXBs)/cataclysmic variables down to LX = 4.3 x 1032 erg s-1. The two SMC Deep Fields (DFs) are located in the most active star-forming region of the SMC bar, with Deep Field-1 positioned at the most pulsar-rich location identified from previous surveys. Two new pulsars were discovered in outburst, CXOU J004929.7-731058 (P = 892 s) and CXOU J005252.2-721715 (P = 326 s), and three new HMXB candidates were identified. Of the 15 Be-pulsars now known in the field, 13 were detected, with pulsations seen in 9 of them. Ephemerides demonstrate that 6 of the 10 pulsars known to exhibit regular outbursts were seen outside their periastron phase, and quiescent X-ray emission at LX = 10(33-34) erg s-1 is shown to be common. Comparison with ROSAT, ASCA, and XMM-Newton catalogs resulted in positive identification of several previously ambiguous sources. Bright optical counterparts exist for 40 of the X-ray sources, of which 33 are consistent with early-type stars (MV < -2, B-V < 0.2), and are the subject of a companion paper to the reference paper. The results point to an underlying HMXB population density up to double that of active systems. The full catalog of 394 point sources is presented in this table; detailed analyses of the source timing and spectral properties are available in the reference paper. The aim-points for these Chandra observations were as follows: DF1 had J2000.0 coordinates of 00 53 34.50 -72 26 43.2 and DF2 had J2000.0 coordinates of 00 50 41.40 -73 16 10.3. This table was created by the HEASARC in August 2010 based on the electronic version of Table 2 from the reference paper which was obtained from the ApJ web site. This is a service provided by NASA HEASARC .