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21891. 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used as "R" photometry value, although the UCAC2 bandpass is between V and R. YB6: (Yellow-Blue catalog version 6) is unpublished data obtained from complete scans of the NPM and SPM plates performed on the PMM at USNO, Flagstaff Station.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
21892. 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.
21893. The nearby white dwarf/red dwarf pair 40 Eri BC
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.
21894. 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.
21895. The NEWPS catalog from WMAP 5-yr survey
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.
21896. 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.
21898. The NIR tip of RGB. I. JHK photometry of IC1613
ID:
ivo://CDS.VizieR/J/ApJ/858/11
Title:
The NIR tip of RGB. I. JHK photometry of IC1613
Short Name:
J/ApJ/858/11
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on observations from the FourStar near-infrared camera on the 6.5m Baade-Magellan telescope at Las Campanas, Chile, we present calibrations of the JHK luminosities of stars defining the tip of the red giant branch (TRGB) in the halo of the Local Group dwarf galaxy IC1613. We employ metallicity- independent (rectified) T-band magnitudes-constructed using J-, H-, and K-band magnitudes and both (J-H) and (J-K) colors to flatten the upward-sloping red giant branch tips as otherwise seen in their apparent color-magnitude diagrams. We describe and quantify the advantages of working at these particular near-infrared wavelengths, which are applicable to both the Hubble Space Telescope (HST) and the James Webb Space Telescope (JWST). We also note that these same wavelengths can be accessed from the ground for an eventual tie-in to Gaia for absolute astrometry and parallaxes to calibrate the intrinsic luminosity of the TRGB. Adopting the color terms derived from the IC 1613 data, as well as the zero points from a companion study of the Large Magellanic Cloud, whose distance is anchored to the geometric distances of detached eclipsing binaries, we find a true distance modulus of 24.32+/-0.02 (statistical) +/-0.05mag (systematic) for IC 1613, which compares favorably with the recently published multi-wavelength, multi-method consensus modulus of 24.30+/-0.05mag by Hatt et al. (2017, J/ApJ/845/146).
21899. The 236.6-5400.0nm spectrum of CrI
ID:
ivo://CDS.VizieR/J/ApJ/700/720
Title:
The 236.6-5400.0nm spectrum of CrI
Short Name:
J/ApJ/700/720
Date:
21 Oct 2021
Publisher:
CDS
Description:
Precision laboratory measurements are presented for 1963 CrI lines spanning the near-ultraviolet into the thermal infrared. Classifications, based on the analysis by Kiess (1953, J. Res. Natl Bur. Stand., 51, 247), are presented. The measurements were obtained from Fourier transform spectra in the archives of the National Solar Observatory.
21900. The North 20cm Survey
ID:
ivo://CDS.VizieR/VIII/17
Title:
The North 20cm Survey
Short Name:
VIII/17
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains a list of 30239 radio sources at 1.4GHz over the declination range of -5 to +82 degrees. This catalog is based on the Green Bank 1.4GHz Northern Sky Survey (Condon and Broderick, 1986, Cat. VIII/6) which was generated using the Green Bank 300 foot (91m) telescope. The threshold for identifying a 1.4GHz radio source was set at 100mJy. The catalog data include the source name, a confusion flag, right ascension (1950), declination (1950), 1.4GHz flux, a flag to indicate if the source is extended at 20cm, 4.85GHz flux (from Becker et al., 1991, Cat. VIII/13), a flag to indicate if the source is extended at 6cm, 365MHz flux (from the Texas Survey, Douglas et al. 1980; see Cat. VIII/42)), spectral index between 6 and 20 cm, and spectral index between 20 and 80 cm. Where possible, the source name is derived from the 6cm catalog of Becker et al. 1991 (Cat. VIII/13).

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