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- ID:
- ivo://astron.nl/lolss/q/cone
- Title:
- LoLSS source catalog
- Short Name:
- LoLSS catalog
- Date:
- 02 Feb 2023 15:08:05
- Publisher:
- ASTRON
- Description:
- This service provides the source catalogue of the LOFAR LBA Sky Survey (LoLSS).
- ID:
- ivo://astron.nl/lotss_dr2/q/gaus_cone
- Title:
- LoTSS-DR2 Gaussian catalog cone search
- Short Name:
- LoTSS-DR2 Gaus
- 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 gaussian component catalogue.
- 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://org.gavo.dc/lotsspol/q/ssa
- Title:
- LoTSS DR2 Polarization spectra
- Short Name:
- lotsspol SSAP
- Date:
- 27 Dec 2024 08:31:02
- Publisher:
- The GAVO DC team
- Description:
- The LOFAR Two Meter Sky Survey LoTSS DR2 (:bibcode:`2022A&A...659A...1S`) obtained radio data from 27% of the northern sky between 120 and 168 MHz in the year 2014 through 2020. This service publishes polarization spectra of extragalactic radio sources (radio galaxies and blazars) and the rotation measures derived from them. We also give redshifts for all sources. The data has a spatial resolution of 20 arcsec.
- ID:
- ivo://org.gavo.dc/lotsspol/q/cone
- Title:
- LoTSS DR2 Rotation Measures
- Short Name:
- lotsspol SCS
- Date:
- 27 Dec 2024 08:31:02
- Publisher:
- The GAVO DC team
- Description:
- The LOFAR Two Meter Sky Survey LoTSS DR2 (:bibcode:`2022A&A...659A...1S`) obtained radio data from 27% of the northern sky between 120 and 168 MHz in the year 2014 through 2020. This service publishes polarization spectra of extragalactic radio sources (radio galaxies and blazars) and the rotation measures derived from them. We also give redshifts for all sources. The data has a spatial resolution of 20 arcsec.
- ID:
- ivo://astron.nl/lotss_dr2/q/src_cone
- Title:
- LoTSS-DR2 Source catalog cone search
- Short Name:
- LoTSS-DR2 Source
- 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 source catalogue.
- ID:
- ivo://org.gavo.dc/magic/q/ssa
- Title:
- Magic Public Spectra
- Short Name:
- Magic SSAP
- Date:
- 27 Dec 2024 08:31:04
- Publisher:
- The GAVO DC team
- Description:
- The MAGIC project observes the VHE sky (GeV~TeV) through Cherenkov radiation events. The project is operating since 2004 and with the support from the Spain-VO team they provide data access through a VO-SSAP and web services. This service re-publishes the data with homogeneized in flux units (given here in 'erg/(s.cm2)'). Photon energy values in are transfomred to frequencies.
- ID:
- ivo://bsdc.icranet.org/magic/q/ssa
- Title:
- Magic Public Spectra SSAP Interface
- Short Name:
- Magic SSAP
- Date:
- 17 May 2017 10:12:24
- Publisher:
- BSDC
- Description:
- The MAGIC project observes the VHE sky (GeV~TeV) through Cherenkov radiation events. The project is operating since 2004 and with the support from the Spain-VO team they provide data access through a VO-SSAP and web services. Our goal here is to provide the same kind of service with the difference that the data is transformed and homogeneized in its flux units, to values in 'erg/(s.cm2)', and photon energy values in equivalent 'Hz' frequency values.
- ID:
- ivo://wfau.roe.ac.uk/twompz-dsa
- Title:
- 2MASS Photometric Redshift catalogue (2MPZ)
- Date:
- 23 Jan 2024 09:45:12
- Publisher:
- WFAU, Institute for Astronomy, University of Edinburgh
- Description:
- The 2MASS Photometric Redshift catalogue (2MPZ) is constructed by cross-matching 2MASS XSC, WISE and SuperCOSMOS all-sky samples and employing the artificial neural network approach (the ANNz algorithm, Collister & Lahav 2004), trained on several redshift surveys (2MRS, SDSS, 6dFGS, 2dFGRS and ZCAT). The derived photometric redshifts have errors nearly independent of distance, with an all-sky accuracy of Ïz = 0.015, and a very small percentage of outliers. These redshift estimates have a typical precision of 12% for all the 2MASS XSC galaxies that lack spectroscopy. The resulting 2MPZ sample contains almost 1 million galaxies with a median redshift of z=0.07. This catalogue is described in Bilicki et al. 2014, ApJS, 210, 9.
