- ID:
- ivo://CDS.VizieR/J/ApJS/185/198
- Title:
- The Cepheus flare observed with IRAC and MIPS
- Short Name:
- J/ApJS/185/198
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Spitzer Infrared Array Camera (IRAC; ~2deg^2^) and Multiband Imaging Photometer for Spitzer (MIPS; ~8deg^2^) observations of the Cepheus Flare, which is associated with the Gould Belt, at an approximate distance of ~300pc. Around 6500 sources are detected in all four IRAC bands, of which ~900 have MIPS 24um detections. We identify 133 young stellar object (YSO) candidates using color-magnitude diagram techniques, and a large number of the YSO candidates are associated with the NGC 7023 reflection nebula. Cross-identifications were made with the Guide Star Catalog II and the IRAS Faint Source Catalog, and spectral energy distributions (SEDs) were constructed. SED modeling was conducted to estimate the degree of infrared excess. It was found that a large majority of disks were optically thick accreting disks, suggesting that there has been little disk evolution in these sources. Nearest-neighbor clustering analysis identified four small protostellar groups (L1228, L1228N, L1251A, and L1251B) with 5-15 members each and the larger NGC 7023 association with 32 YSO members. The star-formation efficiency for cores with clusters of protostars and for those without clusters was found to be ~8% and ~1%, respectively. The cores L1155, L1241, and L1247 are confirmed to be starless down to our luminosity limit of L_bol_=0.06L_{sun}_.
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- ID:
- ivo://CDS.VizieR/J/ApJS/201/30
- Title:
- The Chandra COSMOS survey. III.
- Short Name:
- J/ApJS/201/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Chandra COSMOS Survey (C-COSMOS) is a large, 1.8Ms, Chandra program that has imaged the central 0.9deg^2^ of the COSMOS field down to limiting depths of 1.9x10^-16^erg/cm^2^/s in the soft (0.5-2keV) band, 7.3x10^-16^erg/cm^2^/s in the hard (2-10keV) band, and 5.7x10^-16^erg/cm^2^/s in the full (0.5-10keV) band. In this paper we report the i, K, and 3.6um identifications of the 1761 X-ray point sources. We use the likelihood ratio technique to derive the association of optical/infrared counterparts for 97% of the X-ray sources. For most of the remaining 3%, the presence of multiple counterparts or the faintness of the possible counterpart prevented a unique association. For only 10 X-ray sources we were not able to associate a counterpart, mostly due to the presence of a very bright field source close by. Only two sources are truly empty fields. The full catalog, including spectroscopic and photometric redshifts and classification described here in detail, is available online.
- ID:
- ivo://CDS.VizieR/J/ApJ/697/1695
- Title:
- The Chandra survey of the SMC "Bar". II.
- Short Name:
- J/ApJ/697/1695
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the most likely optical counterparts of 113 X-ray sources detected in our Chandra survey of the central region of the Small Magellanic Cloud (SMC) based on the OGLE-II and Magellanic Clouds Photometric Survey catalogs. We estimate that the foreground contamination and chance coincidence probability are minimal for the bright optical counterparts (corresponding to OB type stars; 35 in total). We propose here for the first time 13 high-mass X-ray binaries, of which four are Be/X-ray binaries (Be-XRBs), and we confirm the previous classification of 18 Be-XRBs. We estimate that the new candidate Be-XRBs have an age of ~15-85Myr, consistent with the age of Be stars.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/24
- Title:
- The COSMOS2015 catalog
- Short Name:
- J/ApJS/224/24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the COSMOS2015 catalog, which contains precise photometric redshifts and stellar masses for more than half a million objects over the 2deg^2^ COSMOS field. Including new YJHKs images from the UltraVISTA-DR2 survey, Y-band images from Subaru/Hyper-Suprime-Cam, and infrared data from the Spitzer Large Area Survey with the Hyper-Suprime-Cam (SPLASH) Spitzer legacy program, this near-infrared-selected catalog is highly optimized for the study of galaxy evolution and environments in the early universe. To maximize catalog completeness for bluer objects and at higher redshifts, objects have been detected on a {chi}^2^ sum of the YJHKs and z^++^ images. The catalog contains ~6x10^5^ objects in the 1.5deg^2^ UltraVISTA-DR2 region and ~1.5x10^5^ objects are detected in the "ultra-deep stripes" (0.62deg^2^) at Ks<=24.7 (3{sigma}, 3", AB (AB) magnitude). Through a comparison with the zCOSMOS-bright spectroscopic redshifts, we measure a photometric redshift precision of {sigma}_{Delta}z/(1+zs)_=0.007 and a catastrophic failure fraction of {eta}=0.5%. At 3<z<6 , using the unique database of spectroscopic redshifts in COSMOS, we find {sigma}_{Delta}z/(1+zs)_=0.021 and {eta}=13.2% . The deepest regions reach a 90% completeness limit of 10^10^M_{sun}_ to z=4. Detailed comparisons of the color distributions, number counts, and clustering show excellent agreement with the literature in the same mass ranges. COSMOS2015 represents a unique, publicly available, valuable resource with which to investigate the evolution of galaxies within their environment back to the earliest stages of the history of the universe.
- ID:
- ivo://CDS.VizieR/J/ApJ/718/587
- Title:
- The Fermi-AT20G catalog
- Short Name:
- J/ApJ/718/587
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The high-frequency radio sky, like the gamma-ray sky surveyed by the Fermi satellite, is dominated by flat spectrum radio quasars and BL Lac objects at bright flux levels. To investigate the relationship between radio and gamma-ray emission in extragalactic sources, we have cross-matched the Australia Telescope 20 GHz survey catalog (AT20G) with the Fermi-LAT 1 year Point Source Catalog (1FGL). The 6.0sr of sky covered by both catalogs (DEC<0{deg},|b|>1.5{deg}) contains 5890 AT20G radio sources and 604 1FGL gamma-ray sources. The AT20G source positions are accurate to within ~1 arcsec and, after excluding known Galactic sources, 43% of Fermi 1FGL sources have an AT20G source within the 95% Fermi confidence ellipse. Monte Carlo tests imply that at least 95% of these matches are genuine associations. Only five gamma-ray sources (1% of the Fermi catalog) have more than one AT20G counterpart in the Fermi error box. The AT20G matches also generally support the active galactic nucleus (AGN) associations in the First LAT AGN Catalog. We find a trend of increasing gamma-ray flux density with 20GHz radio flux density. The Fermi detection rate of AT20G sources is close to 100% for the brightest 20GHz sources, decreasing to 20% at 1Jy, and to roughly 1% at 100mJy. Eight of the matched AT20G sources have no association listed in 1FGL and are presented here as potential gamma-ray AGNs for the first time. We also identify an alternative AGN counterpart to one 1FGL source. The percentage of Fermi sources with AT20G detections decreases toward the Galactic plane, suggesting that the 1FGL catalog contains at least 50 Galactic gamma-ray sources in the southern hemisphere that are yet to be identified.
- ID:
- ivo://CDS.VizieR/J/ApJ/706/L7
- Title:
- The Fermi LAT sky as seen by INTEGRAL/IBIS
- Short Name:
- J/ApJ/706/L7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this Letter we present the result of the cross correlation between the fourth INTEGRAL/IBIS soft gamma-ray catalog, in the range 20-100keV, and the Fermi LAT bright source list of objects emitting in the 100MeV-100GeV range. The main result is that only a minuscule part of the more than 720 sources detected by INTEGRAL and the population of 205 Fermi LAT sources are detected in both spectral regimes. This is in spite of the mCrab INTEGRAL sensitivity for both galactic and extragalactic sources and the breakthrough, in terms of sensitivity, achieved by Fermi at MeV-GeV energies. The majority of the 14 Fermi LAT sources clearly detected in the fourth INTEGRAL/IBIS catalog are optically identified active galactic nuclei (10) complemented by two isolated pulsars (Crab and Vela) and two high-mass X-ray binaries (LS I +61 303 and LS 5039). Two more possible associations have been found: one is 0FGL J1045.6-5937, possibly the counterpart at high energy of the massive colliding wind binary system Eta Carinae, discovered to be a soft gamma ray emitter by recent INTEGRAL observations and 0FGL J1746.0-2900 coincident with IGR J17459-2902, but still not identified with any known object at lower energy. For the remaining 189 Fermi LAT sources no INTEGRAL counterpart was found and we report the 2{sigma} upper limit in the energy band 20-40keV.
- ID:
- ivo://CDS.VizieR/J/AJ/153/259
- Title:
- The GAMBLES extension of the SLoWPoKES catalog
- Short Name:
- J/AJ/153/259
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The formation and evolution of binary star systems are some of the remaining key questions in modern astronomy. Wide binary pairs (separations >10^3^au) are particularly intriguing because their low binding energies make it difficult for the stars to stay gravitationally bound over extended timescales, and thus to probe the dynamics of binary formation and dissolution. Our previous SLoWPoKES catalogs, I and II, provided the largest and most complete sample of wide-binary pairs of low masses. Here we present an extension of these catalogs to a broad range of stellar masses: the Gaia Assorted Mass Binaries Long Excluded from SloWPoKES (GAMBLES), comprising 8660 statistically significant wide pairs that we make available in a living online database. Within this catalog we identify a subset of 543 long-lived (dissipation timescale >1.5Gyr) candidate binary pairs, of assorted mass, with typical separations between 10^3^ and 10^5.5^ au (0.002-1.5pc), using the published distances and proper motions from the Tycho-Gaia Astrometric Solution and Sloan Digital Sky Survey photometry. Each pair has at most a false positive probability of 0.05; the total expectation is 2.44 false binaries in our sample. Among these, we find 22 systems with 3 components, 1 system with 4 components, and 15 pairs consisting of at least 1 possible red giant. We find the largest long-lived binary separation to be nearly 3.2pc; even so, >76% of GAMBLES long-lived binaries have large binding energies and dissipation lifetimes longer than 1.5Gyr. Finally, we find that the distribution of binary separations is clearly bimodal, corroborating the findings from SloWPoKES and suggesting multiple pathways for the formation and dissipation of the widest binaries in the Galaxy.
- ID:
- ivo://CDS.VizieR/J/ApJ/709/377
- Title:
- The globular cluster system of NGC 4636
- Short Name:
- J/ApJ/709/377
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectroscopic study of the globular clusters (GCs) in the giant elliptical galaxy NGC 4636 in the Virgo Cluster. We selected target GC candidates using the Washington photometry derived from the deep CCD images taken at the KPNO 4m Telescope. Then we obtained the spectra of 164 target objects in the field of NGC 4636 using the Multi-Object Spectroscopy mode of Faint Object Camera and Spectrograph on the Subaru 8.2m Telescope. We have measured the velocities for 122 objects: 105 GCs in NGC 4636, the nucleus of NGC 4636, 11 foreground stars, two background galaxies, and three probable intracluster GCs in the Virgo Cluster. The GCs in NGC 4636 are located in the projected galactocentric radius within 10' (corresponding to 43kpc). The measured velocities for the GCs range from ~300km/s to ~1600km/s, with a mean value of 932^+25^_-22_km/s, which is in good agreement with the velocity for the nucleus of NGC 4636, 928+/-45km/s.
- ID:
- ivo://CDS.VizieR/J/A+A/466/31
- Title:
- The HELLAS2XMM survey. VIII
- Short Name:
- J/A+A/466/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the photometric and spectroscopic identification of 110 hard X-ray selected sources from 5 additional XMM-Newton fields, nearly doubling the original HELLAS2XMM sample. Their 2-10keV fluxes cover the range 6x10^-15^-4x10^-13^erg/cm^2^/s and the total area surveyed is 0.5 square degree at the bright flux limit. We spectroscopically identified 59 new sources, bringing the spectroscopic completeness of the full HELLAS2XMM sample to almost 70% over a total area of 1.4 square degree. We found optical counterparts for 214 out of the 232 X-ray sources of the full sample down to R~25. We measured the flux and luminosity of the [OIII]5007 emission line for 59 of these sources.
- ID:
- ivo://CDS.VizieR/I/324
- Title:
- The Initial Gaia Source List (IGSL)
- Short Name:
- I/324
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Initial Gaia Source List will be the starting point for the Gaia Initial Data Treatment. The Attitude Star Catalog will be used by the first iteration of the on-ground attitude reconstruction.
