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- ID:
- ivo://nrao.archive
- Title:
- The National Radio Astronomy Observatory Authority Name
- Short Name:
- NRAO
- Date:
- 04 Apr 2008 11:10:31
- Publisher:
- The National Radio Astronomy Observatory (NRAO)
- Description:
- The authority identifier for NRAO resources.
- ID:
- ivo://nrao/NRAO
- Title:
- The National Radio Astronomy Observatory (NRAO)
- Short Name:
- NRAO
- Date:
- 20 Feb 2014 21:59:32
- Publisher:
- NRAO
- Description:
- Founded in 1956, the NRAO provides state-of-the-art radio telescope facilities for use by the international scientific community. NRAO telescopes are open to all astronomers regardless of institutional or national affiliation. Observing time on NRAO telescopes is available on a competitive basis to qualified scientists after evaluation of research proposals on the basis of scientific merit, the capability of the instruments to do the work, and the availability of the telescope during the requested time. NRAO also provides both formal and informal programs in education and public outreach for teachers, students, the general public, and the media. The NRAO is funded by the National Science Foundation (NSF) under the terms of a cooperative agreement between the NSF and Associated Universities, Inc. (AUI), a science management corporation.
- 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.
- 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
- 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.
- ID:
- ivo://CDS.VizieR/J/AJ/154/200
- Title:
- The nearby white dwarf/red dwarf pair 40 Eri BC
- Short Name:
- J/AJ/154/200
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new relative orbit solution with new dynamical masses is determined for the nearby white dwarf-red dwarf pair 40 Eri BC. The period is 230.29+/-0.68 years. It is predicted to close slowly over the next half-century, getting as close as 1.32" in early 2066. We determine masses of 0.573+/-0.018 M_{sun}_ for the white dwarf and 0.2036+/-0.0064 M_{sun}_ for the red dwarf companion. The inconsistency of the masses determined by gravitational redshift and dynamical techniques, due to a premature orbit calculation, no longer exists.
21908. The N70E catalogue
- ID:
- ivo://CDS.VizieR/I/241
- Title:
- The N70E catalogue
- Short Name:
- I/241
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The N70E catalogue provides improved mean positions and proper motions for the 718 Basic fundamental stars from the FK5 catalogue in the equatorial zone covering the declination range from -30 to +30 degrees. The catalogue is resulted from revision of the FK5 system on the basis of 36 modern absolute and quasi-absolute catalogues and the four fundamental catalogues FK3, FK4, GC, N30, and revision of FK5 individual positions and proper motions by use of 52 catalogues distributed at the time span from 1900 to 1993. Absolute orientation in space of N70E catalogue is defined by the IAU (1976) system of astronomical constants. Only the machine-readable version of the N70E catalogue is distributed. It contains the positions and proper motions of the stars for the epoch and equinox J2000.0, the mean epochs of individual observed right ascensions and declinations used to determine the final positions, and the mean errors of the final positions and proper motions for the reported epochs.
- ID:
- ivo://CDS.VizieR/J/MNRAS/392/733
- Title:
- The NEWPS catalog from WMAP 5-yr survey
- Short Name:
- J/MNRAS/392/733
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have analysed the efficiency in source detection and flux density estimation of blind and non-blind detection techniques exploiting the MHW2 filter applied to the Wilkinson Microwave Anisotropy Probe (WMAP) 5-yr maps. A comparison with the AT20G bright source sample, with a completeness limit of 0.5Jy and accurate flux measurements at 20GHz, close to the lowest frequency of WMAP maps, has allowed us to assess the completeness and the reliability of the samples detected with the two approaches, as well as the accuracy of flux and error estimates, and their variations across the sky.
21910. The new X-Class catalogue
- ID:
- ivo://CDS.VizieR/J/A+A/652/A12
- Title:
- The new X-Class catalogue
- Short Name:
- J/A+A/652/A12
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Cosmological probes based on galaxy clusters rely on cluster number counts and large-scale structure information. X-ray cluster surveys are well suited for this purpose, since they are far less affected than optical surveys by projection effects, and cluster properties can be predicted with good accuracy. The XMM Cluster Archive Super Survey, X-CLASS, is a serendipitous search of X-ray-detected galaxy clusters in 4176 XMM-Newton archival observations until August 2015. All observations are clipped to exposure times of 10 and 20 ks to obtain uniformity and they span ~269 sq. deg. across the high-Galactic latitude sky (|b|>20deg). The main goal of the survey is the compilation of a well-selected cluster sample suitable for cosmological analyses. We describe the detection algorithm, the visual inspection, the verification process and the redshift validation of the cluster sample, as well as the cluster selection function computed by simulations. We also present the various metadata that are released with the catalogue, along with the redshifts of 124 clusters obtained with a dedicated multi-object spectroscopic follow-up programme. With this publication we release the new X-CLASS catalogue of 1646 well-selected X-ray-detected clusters over a wide sky area, along with their selection function. The sample spans a wide redshift range, from the local Universe up to z~1.5, with 982 spectroscopically confirmed clusters, and over 70 clusters above z=0.8. Because of its homogeneous selection and thorough verification, the cluster sample can be used for cosmological analyses, but also as a test-bed for the upcoming eROSITA observations and other current and future large-area cluster surveys. It is the first time that such a catalogue is made available to the community via an interactive database which gives access to a wealth of supplementary information, images, and data.
