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1991. The fourth U.S. Naval Observatory CCD Astrograph Catalog (UCAC4)
ID:
ivo://org.gavo.dc/ucac4/q/s
Title:
The fourth U.S. Naval Observatory CCD Astrograph Catalog (UCAC4)
Short Name:
ucac4 scs
Date:
27 Dec 2024 08:31:12
Publisher:
The GAVO DC team
Description:
UCAC4 is a compiled, all-sky star catalog covering mainly the 8 to 16 magnitude range in a single bandpass between V and R. Positional errors are about 15 to 20 mas for stars in the 10 to 14 mag range. Proper motions have been derived for most of the about 113 million stars utilizing about 140 other star catalogs with significant epoch difference to the UCAC CCD observations. These data are supplemented by 2MASS photometric data for about 110 million stars and 5-band (B,V,g,r,i) photometry from the APASS (AAVSO Photometric All-Sky Survey) for over 50 million stars. UCAC4 also contains error estimates and various flags. All bright stars not observed with the astrograph have been added to UCAC4 from a set of Hipparcos and Tycho-2 stars. Thus UCAC4 should be complete from the brightest stars to about R=16, with the source of data indicated in flags.
1992. The Gaia-PS1-SDSS (GPS1) Proper Motion Catalog
ID:
ivo://org.gavo.dc/gps1/q/cone
Title:
The Gaia-PS1-SDSS (GPS1) Proper Motion Catalog
Short Name:
GPS1
Date:
27 Dec 2024 08:31:00
Publisher:
The GAVO DC team
Description:
This catalog combines Gaia DR1, Pan-STARRS 1, SDSS and 2MASS astrometry to compute proper motions for 350 million sources across three-fourths of the sky down to a magnitude of mr≈20. Positions of galaxies from Pan-STARRS 1 are used to build a reference frame for PS1, SDSS, and 2MASS data. Gaia DR1 is adapted to that reference frame by exploiting that locally, proper motions are linear. GPS1 has a characteristic systematic error of less than 0.3 mas/yr, and a typical precision of 1.5−2.0 mas/yr. The proper motions have been validated using galaxies, open clusters, distant giant stars and QSOs. In comparison with other published faint proper motion catalogs, GPS1's systematic error (<0.3 mas/yr) is about 10 times better than that of PPMXL and UCAC4 (>2.0 mas/yr). Similarly, its precision (~1.5 mas/yr) is an improvement by ∼ 4 times relative to PPMXL and UCAC4 (∼6.0 mas/yr). For QSOs, the precision of GPS1 is found to be worse (∼2.0−3.0 mas/yr), possibly due to their particular differential chromatic refraction (DCR).
1993. The Galactic Bulge Survey: X-ray observations
ID:
ivo://CDS.VizieR/J/ApJS/194/18
Title:
The Galactic Bulge Survey: X-ray observations
Short Name:
J/ApJS/194/18
Date:
21 Oct 2021
Publisher:
CDS
Description:
We introduce the Galactic Bulge Survey (GBS) and we provide the Chandra source list for the region that has been observed to date. Among the goals of the GBS are constraining the neutron star (NS) equation of state and the black hole (BH) mass distribution via the identification of eclipsing NS and BH low-mass X-ray binaries (LMXBs). The GBS targets two strips of 6{deg}x1{deg} (12deg^2^ in total), one above (1{deg}<b<2{deg}) and one below (-2{deg}<b<-1{deg}) the Galactic plane in the direction of the Galactic center at both X-ray and optical wavelengths. By avoiding the Galactic plane (-1{deg}<b<1{deg}) we limit the influence of extinction on the X-ray and optical emission but still sample relatively large number densities of sources. The survey is designed such that a large fraction of the X-ray sources can be identified from their optical spectra. The X-ray survey, by design, covers a large area on the sky while the depth is shallow using 2ks per Chandra pointing. In this way we maximize the predicted number ratio of (quiescent) LMXBs to cataclysmic variables. The survey is approximately homogeneous in depth to a 0.5-10keV flux of 7.7x10^-14^erg/cm^2^/s. So far, we have covered about two-thirds (8.3deg^2^) of the projected survey area with Chandra providing over 1200 unique X-ray sources. We discuss the characteristics and the variability of the brightest of these sources.
1994. The GALAH+ Survey DR3
ID:
ivo://CDS.VizieR/J/MNRAS/506/150
Title:
The GALAH+ Survey DR3
Short Name:
J/MNRAS/506/150
Date:
12 Jan 2022 13:26:47
Publisher:
CDS
Description:
The ensemble of chemical element abundance measurements for stars, along with precision distances and orbit properties, provides high-dimensional data to study the evolution of the MilkyWay.With this third data release of the Galactic Archaeology with HERMES (GALAH) survey, we publish 678 423 spectra for 588 571 mostly nearby stars (81.2 per cent of stars are within <2 kpc), observed with the HERMES spectrograph at the Anglo-Australian Telescope. This release (hereafter GALAH+ DR3) includes all observations from GALAH Phase 1 (bright, main, and faint survey, 70 per cent), K2-HERMES (17 per cent), TESS-HERMES (5 per cent), and a subset of ancillary observations (8 per cent) including the bulge and >75 stellar clusters. We derive stellar parameters Teff, logg, [Fe/H], vmic, vbroad, and vrad using our modified version of the spectrum synthesis code Spectroscopy Made Easy (SME) and 1D MARCS model atmospheres. We break spectroscopic degeneracies in our spectrum analysis with astrometry from Gaia DR2 and photometry from 2MASS. We report abundance ratios [X/Fe] for 30 different elements (11 of which are based on non-LTE computations) covering five nucleosynthetic pathways. We describe validations for accuracy and precision, flagging of peculiar stars/measurements and recommendations for using our results. Our catalogue comprises 65 per cent dwarfs, 34 per cent giants, and 1 per cent other/unclassified stars. Based on unflagged chemical composition and age, we find 62 per cent young low-alpha, 9 per cent young high-alpha, 27 per cent old high-alpha, and 2 per cent stars with [Fe/H]<=-1. Based on kinematics, 4 per cent are halo stars. Several Value-Added-Catalogues, including stellar ages and dynamics, updated after Gaia eDR3, accompany this release and allow chrono-chemodynamic analyses, as we showcase.
1995. The GALFA-HI compact cloud catalog
ID:
ivo://CDS.VizieR/J/ApJ/758/44
Title:
The GALFA-HI compact cloud catalog
Short Name:
J/ApJ/758/44
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of 1964 isolated, compact neutral hydrogen clouds from the Galactic Arecibo L-Band Feed Array Survey Data Release One. The clouds were identified by a custom machine-vision algorithm utilizing the difference of Gaussian kernels to search for clouds smaller than 20'. The clouds have velocities typically between |V_LSR_|=20 and 400km/s, line widths of 2.5-35km/s, and column densities ranging from 1 to 35x10^18^/cm2. The distances to the clouds in this catalog may cover several orders of magnitude, so the masses may range from less than a solar mass for clouds within the Galactic disk, to greater than 10^4^M_{sun}_for high-velocity clouds (HVCs) at the tip of the Magellanic Stream. To search for trends, we separate the catalog into five populations based on position, velocity, and line width: HVCs; galaxy candidates; cold low-velocity clouds (LVCs); warm, low positive-velocity clouds in the third Galactic quadrant; and the remaining warm LVCs. The observed HVCs are found to be associated with previously identified HVC complexes. We do not observe a large population of isolated clouds at high velocities as some models predict. We see evidence for distinct histories at low velocities in detecting populations of clouds corotating with the Galactic disk and a set of clouds that is not corotating.
1996. The GALFA-HI survey data release 2
ID:
ivo://CDS.VizieR/J/ApJS/234/2
Title:
The GALFA-HI survey data release 2
Short Name:
J/ApJS/234/2
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Galactic Arecibo L-Band Feed Array HI (GALFA-HI) survey data release 2 (DR2). The survey covers the 21cm hyperfine transition of Galactic HI from -650 to 650km/s, with 0.184km/s channel spacing, 4' angular resolution, and 150mK rms noise per 1km/s velocity channel. DR2 covers the entirety of the sky available from the William E. Gordon 305m antenna at Arecibo, from decl. -1{deg}17' to decl. +37{deg}57' across all R.A.: 4 steradians or 32% of the sky. DR2 differs in a number of ways from data release 1, which was released in 2011. DR2 is built from a largely separate set of observations from DR1, which were taken in a much more consistent mode. This consistency, coupled with more careful attention to systematics and more advanced data reduction algorithms, leads to a much higher-quality DR2 data product. We present three data sets for public use: HI data cubes, far- sidelobe stray-radiation-corrected column density maps, and results of the Rolling Hough Transform linear feature detection algorithm.
1997. The GBNCC pulsar survey. V. Pulsar census
ID:
ivo://CDS.VizieR/J/ApJ/892/76
Title:
The GBNCC pulsar survey. V. Pulsar census
Short Name:
J/ApJ/892/76
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Green Bank North Celestial Cap (GBNCC) pulsar survey will cover the entire northern sky ({delta}>-40{deg}) at 350MHz, and is one of the most uniform and sensitive all-sky pulsar surveys to date. We have created a pipeline to reanalyze GBNCC survey data to take a 350MHz census of all pulsars detected by the survey, regardless of their discovery survey. Of the 1413 pulsars in the survey region, we were able to recover 670. For these we present measured signal-to-noise ratios (S/N), flux densities, pulse widths, profiles, and where appropriate, refined measurements of dispersion measures (DMs) (656 out of 670) and new or improved spectral indices (339 out of 670 total, 47 new, 292 improved). We also measure the period-pulse width relation at 350MHz to scale as W{propto}P^-0.27^. Detection scans for several hundred sources were reanalyzed in order to inspect pulsars' single pulse behavior and 223 were found to exhibit evidence of nulling. With a detailed analysis of measured and expected S/N values and the evolving radio frequency interference environment at 350MHz, we assess the GBNCC survey's sensitivity as a function of spin period, DM, and sky position. We find the sky-averaged limiting flux density of the survey to be 0.74mJy. Combining this analysis with PsrPopPy pulsar population simulations, we predict 60/5 nonrecycled/MSP discoveries in the survey's remaining 21000 pointings, and we begin to place constraints on population model parameters.
1998. The GBT 67-93.6GHz spectral line survey of Orion-KL
ID:
ivo://CDS.VizieR/J/AJ/149/162
Title:
The GBT 67-93.6GHz spectral line survey of Orion-KL
Short Name:
J/AJ/149/162
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a 67-93.6GHz spectral line survey of Orion-KL with the new 4mm Receiver on the Green Bank Telescope (GBT). The survey reaches unprecedented depths and covers the low-frequency end of the 3mm atmospheric window which has been relatively unexplored previously. The entire spectral-line survey is published electronically for general use by the astronomical community. The calibration and performance of the 4mm Receiver on the GBT is also summarized.
1999. The 2.3GHz continuum survey of the GEM project
ID:
ivo://CDS.VizieR/J/A+A/556/A1
Title:
The 2.3GHz continuum survey of the GEM project
Short Name:
J/A+A/556/A1
Date:
21 Oct 2021
Publisher:
CDS
Description:
Determining the spectral and spatial characteristics of the radio continuum of our Galaxy is an experimentally challenging endeavour for improving our understanding of the astrophysics of the interstellar medium. This knowledge has also become of paramount significance for cosmology, since Galactic emission is the main source of astrophysical contamination in measurements of the Cosmic Microwave Background radiation. In this paper we present the scope of the Galactic Emission Mapping (GEM) project and its results at 2.3GHz. Its observational program was conceived and developed to reveal the large scale properties of Galactic synchrotron radiation in total intensity and polarisation through a self-consistent set of radio continuum surveys between 408MHz and 10GHz. GEM's unique observational strategy and experimental design aim at the production of foreground templates in order to address the mutual inconsistencies between existing surveys.
2000. The GLEAM 4-Jy (G4Jy) Sample
ID:
ivo://CDS.VizieR/VIII/105
Title:
The GLEAM 4-Jy (G4Jy) Sample
Short Name:
VIII/105
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Murchison Widefield Array (MWA) has observed the entire southern sky (Declination, {delta}<30{deg}) at low radio-frequencies, over the range 72-231MHz. These observations constitute the GaLactic and Extragalactic All-sky MWA (GLEAM) Survey, and we use the extragalactic catalogue (Galactic latitude, |b|>10{deg}) to define the GLEAM 4-Jy (G4Jy) Sample. This is a complete sample of the 'brightest' radio-sources (S_151MHz_>4Jy), the majority of which are active galactic nuclei with powerful radio-jets. Crucially, low-frequency observations allow the selection of such sources in an orientation-independent way (i.e. minimising the bias caused by Doppler boosting, inherent in high-frequency surveys). We then use higher-resolution radio images, and information at other wavelengths, to morphologically classify the brightest components in GLEAM. We also conduct cross-checks against the literature, and perform internal matching, in order to improve sample completeness (which is estimated to be >95.5%). This results in a catalogue of 1,863 sources, making the G4Jy Sample over 10 times larger than that of the revised Third Cambridge Catalogue of Radio Sources (3CRR; S_178MHz_>10.9Jy). Of these G4Jy sources, 78 are resolved by the MWA (Phase-I) synthesised beam (~2' at 200MHz), and we label 67% of the sample as 'single', 26% as 'double', 4% as 'triple', and 3% as having 'complex' morphology at ~1GHz (45" resolution). We characterise the spectral behaviour of these objects in the radio, and find that the median spectral-index is {alpha}=-0.740+/-0.012 between 151MHz and 843MHz, and {alpha}=-0.786+/-0.006 between 151MHz and 1400MHz (assuming a power-law description, S_{nu}_{prop.to}{nu}^{alpha}^), compared to {alpha}=-0.829+/-0.006 within the GLEAM band. Alongside this, our value-added catalogue provides mid-infrared source associations (subject to 6" resolution at 3.4um) for the radio emission, as identified through visual inspection and thorough checks against the literature. As such, the G4Jy Sample can be used as a reliable training set for cross-identification via machine-learning algorithms. We also estimate the angular size of the sources, based on their associated components at ~1GHz, and perform a flux-density comparison for 67 G4Jy sources that overlap with 3CRR. Analysis of multi-wavelength data, and spectral curvature between 72MHz and 20GHz, will be presented in subsequent papers, and details for accessing all G4Jy overlays are provided at https://github.com/svw26/G4Jy.

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