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15611. The Multi-INstrument Burst ARchive (MINBAR)
ID:
ivo://CDS.VizieR/J/ApJS/249/32
Title:
The Multi-INstrument Burst ARchive (MINBAR)
Short Name:
J/ApJS/249/32
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the largest sample of type I (thermonuclear) X-ray bursts yet assembled, comprising 7083 bursts from 85 bursting sources. The sample is drawn from observations with Xenon-filled proportional counters on the long-duration satellites RXTE, BeppoSAX, and International Gamma-Ray Astrophysics Laboratory between 1996 February 8 and 2012 May 3. The burst sources were drawn from a comprehensive catalog of 115 burst sources, assembled from earlier catalogs and the literature. We carried out a consistent analysis for each burst light curve (normalized to the relative instrumental effective area) and provide measurements of rise time, peak intensity, burst timescale, and fluence. For bursts observed with the RXTE/PCA and BeppoSAX/Wide Field Camera we also provide time-resolved spectroscopy, including estimates of bolometric peak flux and fluence, and spectral parameters at the peak of the burst. For 950 bursts observed with the PCA from sources with previously detected burst oscillations, we include an analysis of the high time resolution data, providing information on the detectability and amplitude of the oscillations, as well as where in the burst they are found. We also present analysis of 118,848 observations of the burst sources within the sample time frame. We extracted 3-25keV X-ray spectra from most observations, and (for observations meeting our signal-to-noise criterion) we provide measurements of the flux, spectral colors, and, for selected sources, the position on the color-color diagram, for the best-fit spectral model. We present a description of the sample, a summary of the science investigations completed to date, and suggestions for further studies.
15612. The multiplicity of M dwarfs in young moving groups
ID:
ivo://CDS.VizieR/J/ApJ/846/93
Title:
The multiplicity of M dwarfs in young moving groups
Short Name:
J/ApJ/846/93
Date:
21 Oct 2021
Publisher:
CDS
Description:
We image 104 newly identified low-mass (mostly M-dwarf) pre-main sequence (PMS) members of nearby young moving groups (YMGs) with Magellan Adaptive Optics (MagAO) and identify 27 stellar binaries with instantaneous projected separation as small as 40mas. Fifteen were previously unknown. The total number of multiple systems in this sample including spectroscopic and visual binaries from the literature is 36, giving a raw stellar multiplicity rate of at least 35_-4_^+5^% for this population. In the separation range of roughly 1-300au in which infrared AO imaging is most sensitive, the raw multiplicity rate is at least 24_-4_^+5^% for binaries resolved by the MagAO infrared camera (Clio). The M-star subsample of 87 stars yields a raw multiplicity of at least 30_-4_^+5^% over all separations, 21_-4_^+5^% for secondary companions resolved by Clio from 1 to 300au (23_-4_^+5^% for all known binaries in this separation range). A combined analysis with binaries discovered by the Search for Associations Containing Young stars shows that stellar multiplicity fraction as a function of mass over the range of 0.2 to 1.2M_{sun}_ appears to be linearly flat, in contrast to the field, where multiplicity increases with mass. After bias corrections are applied, the multiplicity of low-mass YMG members (0.2-0.6M_{sun}_) is in excess of the field. The overall multiplicity fraction is also consistent with being constant in age and across YMGs, which suggests that multiplicity rates for this mass range are largely set by 10Myr without appreciable evolution thereafter.
15613. The MWA view of Fermi blazars
ID:
ivo://CDS.VizieR/J/A+A/588/A141
Title:
The MWA view of Fermi blazars
Short Name:
J/A+A/588/A141
Date:
21 Oct 2021
Publisher:
CDS
Description:
Low-frequency radio arrays are opening a new window for the study of the sky, both to study new phenomena and to better characterize known source classes. Being flat-spectrum sources, blazars are so far poorly studied at low radio frequencies. We characterize the spectral properties of the blazar population at low radio frequency, compare the radio and high-energy properties of the gamma-ray blazar population, and search for radio counterparts of unidentified gamma-ray sources. We cross-correlated the 6100-deg^2^ Murchison Widefield Array Commissioning Survey catalogue with the Roma blazar catalogue, the third catalogue of active galactic nuclei detected by Fermi-LAT, and the unidentified members of the entire third catalogue of gamma-ray sources detected by Fermi-LAT. When available, we also added high-frequency radio data from the Australia Telescope 20GHz catalogue.
15614. The MYStIX IR-Excess Source catalog (MIRES)
ID:
ivo://CDS.VizieR/J/ApJS/209/31
Title:
The MYStIX IR-Excess Source catalog (MIRES)
Short Name:
J/ApJS/209/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Massive Young Star-Forming Complex Study in Infrared and X-rays (MYStIX) project provides a comparative study of 20 Galactic massive star-forming complexes (d=0.4-3.6kpc). Probable stellar members in each target complex are identified using X-ray and/or infrared data via two pathways: X-ray detections of young/massive stars with coronal activity/strong winds or (2) infrared excess (IRE) selection of young stellar objects (YSOs) with circumstellar disks and/or protostellar envelopes. We present the methodology for the second pathway using Spitzer/IRAC, 2MASS, and UKIRT imaging and photometry. Although IRE selection of YSOs is well-trodden territory, MYStIX presents unique challenges. The target complexes range from relatively nearby clouds in uncrowded fields located toward the outer Galaxy (e.g., NGC 2264, the Flame Nebula) to more distant, massive complexes situated along complicated, inner Galaxy sightlines (e.g., NGC 6357, M17). We combine IR spectral energy distribution (SED) fitting with IR color cuts and spatial clustering analysis to identify IRE sources and isolate probable YSO members in each MYStIX target field from the myriad types of contaminating sources that can resemble YSOs: extragalactic sources, evolved stars, nebular knots, and even unassociated foreground/background YSOs. Applying our methodology consistently across 18 of the target complexes, we produce the MYStIX IRE Source (MIRES) Catalog comprising 20719 sources, including 8686 probable stellar members of the MYStIX target complexes. We also classify the SEDs of 9365 IR counterparts to MYStIX X-ray sources to assist the first pathway, the identification of X-ray-detected stellar members.
15615. The 2M-ZoA galaxy catalogue
ID:
ivo://CDS.VizieR/J/MNRAS/482/5167
Title:
The 2M-ZoA galaxy catalogue
Short Name:
J/MNRAS/482/5167
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a homogeneous 2MASS bright galaxy catalogue at low Galactic latitudes (|b|<=10.0{deg}, called Zone of Avoidance) which is complete to a Galactic extinction-corrected magnitude of KS^o^<=11.25m. It also includes galaxies in regions of high foreground extinctions (E(B-V)>0.95mag) situated at higher latitudes. This catalogue forms the basis of studies of large-scale structures, flow fields and extinction across the ZoA and complements the ongoing 2MASS Redshift and Tully-Fisher surveys. It comprises 3763 galaxies, 70% of which have at least one radial velocity measurement in the literature. The catalogue is complete up to star density levels of logN*/deg^2^<4.5 and at least for A(K)<0.6mag and likely as high as A(K)=20mag. Thus the ZoA in terms of bright NIR galaxies covers only 2.5-4% of the whole sky. We use a diameter-dependent extinction correction to compare our sample with an unobscured, high-latitude sample. While the correction to the Ks -band magnitude is sufficient, the corrected diameters are too small by about 4" on average. The omission of applying such a diameter-dependent extinction correction may lead to a biased flow field even at intermediate extinction values as found in the 2MRS survey. A slight dependence of galaxy colour with stellar density indicates that unsubtracted foreground stars make galaxies appear bluer. Furthermore, far-infrared sources in the DIRBE/IRAS extinction maps that were not removed at low latitudes affect the foreground extinction corrections of three galaxies and may weakly affect a further estimated ~20% of our galaxies.
15616. The NAN complex. II. MIPS observations
ID:
ivo://CDS.VizieR/J/ApJS/193/25
Title:
The NAN complex. II. MIPS observations
Short Name:
J/ApJS/193/25
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present observations of ~7deg^2^ of the North American and Pelican Nebulae region at 24, 70, and 160um with the Spitzer Space Telescope Multiband I] ing Photometer for Spitzer (MIPS). We incorporate the MIPS observations with earlier Spitzer Infrared Array Camera (IRAC) observations, as well as archival near-infrared (IR) and optical data. We use the MIPS data to identify 1286 young stellar object (YSO) candidates. IRAC data alone can identify 806 more YSO candidates, for a total of 2076 YSO candidates. Prior to the Spitzer observations, there were only ~200 YSOs known in this region. Three subregions within the complex are highlighted as clusters: the Gulf of Mexico, the Pelican, and the Pelican's Hat. The Gulf of Mexico cluster is subject to the highest extinction (A_V_ at least ~30) and has the widest range of infrared colors of the three clusters, including the largest excesses and by far the most point-source detections at 70um. Just 3% of the cluster members were previously identified; we have redefined this cluster as about 10-100 times larger (in projected area) than was previously realized.
15617. The NAN complex. I. IRAC observations
ID:
ivo://CDS.VizieR/J/ApJ/697/787
Title:
The NAN complex. I. IRAC observations
Short Name:
J/ApJ/697/787
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a 9deg^2^ map of the North American and Pelican Nebulae regions obtained in all four Infrared Array Camera (IRAC) channels with the Spitzer Space Telescope. The resulting photometry is merged with that at JHKs from Two Micron All Sky Survey and a more spatially limited BVI survey from previous ground-based work. We use a mixture of color-color diagrams to select a minimally contaminated set of more than 1600 objects that we claim are young stellar objects (YSOs) associated with the star-forming region. Because our selection technique uses infrared excess as a requirement, our sample is strongly biased against inclusion of Class III YSOs. The distribution of IRAC spectral slopes for our YSOs indicates that most of these objects are Class II, with a peak toward steeper spectral slopes but a substantial contribution from a tail of Flat spectrum and Class I type objects. By studying the small fraction of the sample that is optically visible, we infer a typical age of a few Myr for the low-mass population. The young stars are clustered, with about a third of them located in eight clusters that are located within or near the LDN 935 dark cloud. Half of the YSOs are located in regions with surface densities higher than 1000YSOs/deg^2^. The Class I objects are more clustered than the Class II stars.
15618. The nature of hyper luminous infrared galaxies
ID:
ivo://CDS.VizieR/J/A+A/654/A117
Title:
The nature of hyper luminous infrared galaxies
Short Name:
J/A+A/654/A117
Date:
22 Feb 2022
Publisher:
CDS
Description:
Hyperluminous infrared galaxies (HLIRGs) are shown to have been more abundant in early epochs. The small samples used in earlier studies are not sufficient to draw robust statistical conclusions regarding the physical properties and the power sources of these extreme infrared (IR) bright galaxies. We make use of multi-wavelength data of a large hyper luminous galaxy sample to derive the main physical properties, such as stellar mass, star formation rate (SFR), volume density, and the contribution to the cosmic stellar mass density and the cosmic SFR density. We also study the black hole (BH) growth rate and its relationship with the SFR of the host galaxy. We selected 526 HLIRGs in three deep fields (Bootes, Lockman-Hole, and ELAIS-N1) and adopted two spectral energy distribution (SED) fitting codes: CIGALE, which assumes energy balance, and CYGNUS, which is based on radiative transfer models and does not adopt an energy balance principle. We used two different active galactic nucleus (AGN) models in CIGALE and three AGN models in CYGNUS to compare results that were estimated using different SED fitting codes and a range of AGN models. The stellar mass, total IR luminosity, and AGN luminosity agree well among different models, with a typical median offset of 0.1dex. The SFR estimates show the largest dispersions (up to 0.5dex). This dispersion has an impact on the subsequent analysis, which may suggest that the previous contradictory results could partly have been due to the different choices in methods. HLIRGs are ultra-massive galaxies, with 99% of them having stellar masses larger than 10^11^M_{sun}_. Our results reveal a higher space density of ultra-massive galaxies than what was found by previous surveys or predicted via simulations. We find that HLIRGs contribute more to the cosmic SFR density as redshift increases. In terms of BH growth, the two SED fitting methods provide different results. We can see a clear trend in whereby SFR decreases as AGN luminosity increases when using CYGNUS estimates. This may possibly imply quenching by AGN in this case, whereas this trend is much weaker when using CIGALE estimates. This difference is also influenced by the dispersion between SFR estimates obtained by the two codes.
15619. The Naval Observatory Merged Astrometric Dataset
ID:
ivo://astronet.ru/cas/nomad
Title:
The Naval Observatory Merged Astrometric Dataset
Short Name:
nomad
Date:
17 Jun 2006 18:44:05
Publisher:
Sternberg Astronomical Institute Virtual Observatory Project
Description:
The U.S. Naval Observatory (USNO) announces the release of the first version of the Naval Observatory Merged Astrometric Dataset (NOMAD). The almost 100 GB dataset contains astrometric and photometric data for about 1.1 billion stars derived from the Hipparcos, Tycho-2, UCAC2, Yellow-Blue 6, and USNO-B catalogs for astrometry and optical photometry, supplemented by 2MASS near-infrared photometry. For each unique star the "best" astrometric and photometric data are chosen from the source catalogs and merged into a single dataset. A sequence of priorities is followed and NOMAD contains flags to identify the source catalogs and gives cross-reference identifications. This first release of NOMAD is not a compiled catalog; that is, if a star is identified in more than 1 of the above mentioned catalogs, only 1 catalog entry is chosen. Thus the local and global systematic errors of the various source catalogs will be present in this version of NOMAD. All source catalogs astrometric data are on the International Celestial Reference System within the limitations of the source catalogs. Catalogs used: Hipparcos Catalogue: Positions, proper motions and errors are used; however, no parallaxes are included in NOMAD. Tycho-2: is a compiled catalog with proper motions derived from the combination of Hipparcos satellite measures (mainly its star tracker data) and over 100 ground-based astrometric catalogs which provided the early epoch data. Most of the Tycho B and V magnitudes (which includes Hipparcos stars) went into NOMAD as well. UCAC2: is also a compiled catalog, including all catalogs used for Tycho-2 (thus also including Tycho and Hipparcos astrometric data), plus the recent epoch ground-based observations of the UCAC project. However, only 86\% of the sky are covered by UCAC2 (the north celestial pole area is missing). For stars not in USNO-B, the UCAC2 magnitude has been used as "R" photometry value, although the UCAC2 bandpass is between V and R. YB6: (Yellow-Blue catalog version 6) is unpublished data obtained from complete scans of the NPM and SPM plates performed on the PMM at USNO, Flagstaff Station. The limiting magnitude is about 18 and YB6 is the major source of faint B and V magnitudes in NOMAD. 2MASS: the near IR photometry without errors or flags has been copied into NOMAD. For those stars without optical counterparts, the 2MASS astrometric information was used (no proper motions). USNO-B: provides positions and proper motions for most faint stars in NOMAD. Most R photometry in NOMAD comes from this catalog. For more details, see the catalog introductions for each individual catalog used in NOMAD. NOMAD is not a compiled catalog, no average values are taken if a star appears in more than 1 source catalog. Each astrometric and photometric entry in NOMAD is taken from a specific source catalog. The priority order is as follows: astrometry brighter than 8 mag: Hipparcos Tycho-2 UCAC2 astrometry of fainter stars: Hipparcos UCAC2 Tycho-2 USNO-B YB6 2MASS photometry: optical Tycho-2 (incl. Hipparcos stars) YB6 USNO-B UCAC2 photometry: near IR 2MASS
15620. The 2nd MSFRs Omnibus X-ray Catalog (MOXC2)
ID:
ivo://CDS.VizieR/J/ApJS/235/43
Title:
The 2nd MSFRs Omnibus X-ray Catalog (MOXC2)
Short Name:
J/ApJS/235/43
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the second installment of the Massive Star-forming Regions (MSFRs) Omnibus X-ray Catalog (MOXC2), a compilation of X-ray point sources detected in Chandra/ACIS observations of 16 Galactic MSFRs and surrounding fields. MOXC2 includes 13 ACIS mosaics, three containing a pair of unrelated MSFRs at different distances, with a total catalog of 18396 point sources. The MSFRs sampled range over distances of 1.3kpc to 6kpc and populations varying from single massive protostars to the most massive Young Massive Cluster known in the Galaxy. By carefully detecting and removing X-ray point sources down to the faintest statistically significant limit, we facilitate the study of the remaining unresolved X-ray emission. Through comparison with mid-infrared images that trace photon-dominated regions and ionization fronts, we see that the unresolved X-ray emission is due primarily to hot plasmas threading these MSFRs, the result of feedback from the winds and supernovae of massive stars. The 16 MSFRs studied in MOXC2 more than double the MOXC1 sample, broadening the parameter space of ACIS MSFR explorations and expanding Chandra's substantial contribution to contemporary star formation science.

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