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- ID:
- ivo://org.gavo.dc/emi/q/s
- Title:
- VLBI images of Lockman Hole radio sources
- Short Name:
- VLBI-Lockman
- Date:
- 16 Jan 2024 16:41:20
- Publisher:
- The GAVO DC team
- Description:
- These are 1.4GHz Very Long Baseline Interferometry images of 532 radio sources with a flux density exceeding 100uJy as determined by Ibar et al. (2009, MNRAS, 397, 281), obtained between 2010-06-03 and 2010-09-03. For all fields, we give frames processed using natural weighting to preserve maximal sensitivity. For the 65 detected sources, we additionally give frames processed using uniform weighting to suppress sidelobes (see Middelberg et al. 2013, A&A 551, 97 for details) in flux density measurements. Some sources have larger images to cover a larger area because the initial coordinates were not sufficiently accurate.
- ID:
- ivo://org.gavo.dc/lswscans/res/positions/siap
- Title:
- HDAP -- Heidelberg Digitized Astronomical Plates
- Short Name:
- hdap_siap
- Date:
- 31 Oct 2023 19:15:05
- Publisher:
- The GAVO DC team
- Description:
- Scans of plates kept at Landessternwarte Heidelberg-Königstuhl. They were obtained at location, at the German-Spanish Astronomical Center (Calar Alto Observatory), Spain, and at La Silla, Chile. The plates cover a time span between 1880 and 1999. Specifically, HDAP is essentially complete for the plates taken with the Bruce telescope, the Walz reflector, and Wolf's Doppelastrograph at both the original location in Heidelberg and its later home on Königstuhl.
- ID:
- ivo://fai.kz/fai_agn/q/i
- Title:
- AGN observations obtained at FAI
- Short Name:
- fai_agn siap
- Date:
- 10 Oct 2023 11:48:20
- Publisher:
- Fesenkov Astrophysical Institute
- Description:
- The database of Active Galactic Nuclea (AGN) photometrical observations obtained on defferent telescopes at Fesenkov Astrophysical Institute, Almaty, Kazakhstan since 2016. Observations were carried out in the optical range.
- ID:
- ivo://fai.kz/grb_photometry/q/i
- Title:
- Photometrical observations of GRB
- Short Name:
- grb siap
- Date:
- 10 Oct 2023 11:48:20
- Publisher:
- Fesenkov Astrophysical Institute
- Description:
- The database of Gamma Ray Burst (GRB) photometrical observations obtained on defferent telescopes at Fesenkov Astrophysical Institute, Almaty, Kazakhstan. Observations were carried out in the optical range.
- ID:
- ivo://astron.nl/lotss_dr2/q/query_mosaics
- Title:
- LoTSS-DR2 mosaics
- Short Name:
- "Mosaics"
- Date:
- 28 Sep 2023 14:12:45
- Publisher:
- ASTRON
- Description:
- In this data release from the ongoing LOw-Frequency ARray (LOFAR) Two-metre Sky Survey (LoTSS) we present 120-168 MHz images covering 27% of the northern sky. Our coverage is split into two regions centred at approximately 12h45m +44°30′ and 1h00m +28°00′ and spanning 4178 and 1457 square degrees respectively. The images were derived from 3,451 hrs (7.6 PB) of LOFAR High Band Antenna data which were corrected for the direction-independent instrumental properties as well as direction-dependent ionospheric distortions during extensive, but fully automated, data processing. A catalogue of 4,395,448 radio sources is derived from our total intensity (Stokes I) maps, where the majority of these have never been detected at radio wavelengths before. At 6′′ resolution, our full bandwidth Stokes I continuum maps with a central frequency of 144 MHz have: a median rms sensitivity of 83 μ Jy/beam; a flux density scale accuracy of approximately 10%; an astrometric accuracy of 0.2′′; and we estimate the point-source completeness to be 90% at a peak brightness of 0.8 mJy/beam. By creating three 16 MHz bandwidth images across the band we are able to measure the in-band spectral index of many sources, albeit the error on the derived spectral index is > ±0.2 which is a consequence of our flux-density scale accuracy and small fractional bandwidth. Our circular polarisation (Stokes V) 20′′ resolution 120-168 MHz continuum images have a median rms sensitivity of 95 μ Jy/beam, and we estimate a Stokes I to Stokes V leakage of 0.056%. Our linear polarisation (Stokes Q and Stokes U) image cubes consist of 480 97.6 kHz wide planes and have a median rms sensitivity per plane of 10.8mJy/beam at 4′ and 2.2mJy/beam at 20′′; we estimate the Stokes I to Stokes Q/U leakage to be approximately 0.2%. Here we characterise and publicly release our Stokes I, Q, U and V images in addition to the calibrated uv-data to facilitate the thorough scientific exploitation of this unique dataset. This service queries the Stokes I continuum mosaic images.
- ID:
- ivo://astron.nl/apertif_dr_bootes/q/cutout
- Title:
- Apertif DR Bootes - Mosaic
- Short Name:
- DR Bootes
- Date:
- 23 Jun 2023 13:45:11
- Publisher:
- ASTRON
- Description:
- This service provides mosaic from the images of the Apertif DR Bootes.
- ID:
- ivo://org.gavo.dc/liverpool/res/rawframes/rawframes
- Title:
- Liverpool Quasar Lens Monitoring
- Short Name:
- liverpool.rawfra
- Date:
- 20 Apr 2023 00:19:47
- Publisher:
- The GAVO DC team
- Description:
- This collection includes optical monitorings of gravitationally lensed quasars. The frames can be used to make light curves of quasar images and field objects. From quasar light curves, one may measure time delays and flux ratios, analyse variability and chromaticity, etc. These direct analyses/measurements are basic tools for different astrophysical studies, e.g., expansion rate of the Universe, mechanism of intrinsic variability in quasars, accretion disk structure, supermassive black holes, dark halos of galaxies (dust, collapsed dark matter, smoothly distributed dark matter,...)
- ID:
- ivo://org.gavo.dc/rosat/q/im
- Title:
- ROSAT Survey and Pointed Images
- Short Name:
- ROSAT images
- Date:
- 20 Apr 2023 00:06:45
- Publisher:
- The GAVO DC team
- Description:
- Images taken by the ROSAT x-ray observatory. This comprises both pointed observations and images taken within the all-sky survey.
- ID:
- ivo://org.gavo.dc/boydende/q/data
- Title:
- Boyden Station ADH Plates in Germany
- Short Name:
- boydende.data
- Date:
- 21 Mar 2023 00:03:28
- Publisher:
- The GAVO DC team
- Description:
- The Armagh-Dunsink-Harvard Becker-Schmidt Telescope was deployed at Boyden Station, Maselspoort South Africa between 1965 and 1970. During that time, astronomers from Bamberg, Heidelberg, Hamburg and Münster took astronomical images there, with a focus on old star clusters, the Magellanic clouds, and the southern milky way. This service provides scans of the plates obtained.
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