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- ID:
- ivo://CDS.VizieR/J/AJ/128/1646
- Title:
- The Galactic Center region at 330MHz
- Short Name:
- J/AJ/128/1646
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a wide-field, subarcminute-resolution VLA image of the Galactic center region at 330MHz. With a resolution of ~7"x12" and an rms noise of 1.6mJy/beam, this image represents a significant increase in resolution and sensitivity over the previously published VLA image at this frequency. The improved sensitivity has more than tripled the census of small-diameter sources in the region, has resulted in the detection of two new nonthermal filaments (NTFs), 18 NTF candidates, and 30 pulsar candidates, reveals previously known extended sources in greater detail, and has resulted in the first detection of Sagittarius A* in this frequency range.
21723. 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.
- ID:
- ivo://astronet.ru/cas/galah_dr2
- Title:
- The GALAH survey: Second data release (Buder+, 2018)
- Short Name:
- galah_dr2
- Date:
- 17 Jun 2006 18:44:05
- Publisher:
- Sternberg Astronomical Institute Virtual Observatory Project
- Description:
- </pre><p>GALAH is a large-scale stellar spectroscopic survey project exploring the history of star formation, chemical evolution, stellar migration and minor mergers in the Milky Way. One of the main science goals of GALAH is to use chemical tagging to identify groups of stars that formed at the same place and time, even though they have dispersed throughout the Galaxy, using the similarity of their chemical abundance patterns. Using the HERMES spectrograph at the Anglo-Australian Telescope, we collect high-resolution (R~28,000) spectra for 360 stars simultaneously. These stars are selected simply in magnitude (14>V>12), Galactic latitude (|b|>10) and declination (dec<+10) to maximise our ability to learn about the underlying structure of the Galaxy. <p>There are 342,682 unique stars in DR2, observed between January 2014 and January 2018. For these stars, we have derived radial velocities, stellar parameters, and the abundances of up to 23 elements per star.
- 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.
- 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.
- 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://svo.cab/cat/gwp
- Title:
- The Garraf Wide Pairs (GWP) catalogue (2016)
- Short Name:
- GWP
- Date:
- 21 Apr 2022 13:26:14
- Publisher:
- SVO/CAB
- Description:
- The Garraf Wide Pairs (GWP) catalogue (2016)
21729. The GAVO ADQL Reference Card
- ID:
- ivo://org.gavo.dc/misc/adqlref
- Title:
- The GAVO ADQL Reference Card
- Short Name:
- GAVO ADQL ref
- Date:
- 27 Dec 2024 08:31:01
- Publisher:
- The GAVO DC team
- Description:
- GAVO's ADQL reference card briefly gives an overview of the SQL dialect used in the VO. It is available as a PDFfile and as Scribus source under the CC-BY license.
21730. The GAVO data centre
- ID:
- ivo://org.gavo.dc
- Title:
- The GAVO data centre
- Short Name:
- GAVO DC
- Date:
- 29 May 2024 06:02:44
- Publisher:
- The GAVO DC team
- Description:
- The GAVO data centre provides VO publication services to all interested parties on behalf of the German Astrophysical Virtual Observatory.
