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- 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://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://irsa.ipac/2MASS/Images/Allsky
- Title:
- 2MASS All-Sky Image Atlas
- Short Name:
- 2MASS_Allsky
- Date:
- 01 Oct 2024
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- The 2MASS All-Sky Data Release contains Image and Catalog data covering 99.998% of the sky, derived from all northern and southern Survey observations. The All-Sky Release products include a Point Source Catalog (PSC), containing positions and photometry for 470,992,970 objects, an Extended Source Catalog (XSC), containing positions, photometry and basic shape information for 1,647,599 resolved sources, most of which are galaxies, and the Image Atlas, containing over 4,121,439 J, H and Ks FITS images covering the sky.
- ID:
- ivo://irsa.ipac/2MASS/Images/Cal
- Title:
- 2MASS Calibration Image Atlas
- Short Name:
- 2MASS_Cal
- Date:
- 01 Oct 2024
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- Photometric calibration for 2MASS was performed using observations of calibration fields made at regular intervals during each night of survey operations. Measurements of standard stars in the fields were used to derive the photometric zero point offsets as a function of time during each night. Atmospheric extinction coefficients were derived from 2MASS observations made over long periods. 2MASS calibration fields, or tiles, are 1° long in declination and approximately 8.5' wide in right ascension. There are 35 regular survey calibration fields distributed at approximately two hour intervals in right ascension near declinations of approximately -30°, 0° and +30°. An additional five calibration fields were defined in and around the Large and Small Magellanic Clouds to support the deep observation (6x) campaign towards the end of survey operations. Calibration scan Atlas Images, and Point and Extended Source Working Databases (Cal-PSWDB and Cal-XSWDB), analogous to those from the main survey, were produced from the calibration scan pipeline data reduction.
- ID:
- ivo://irsa.ipac/2MASS/Images/Full
- Title:
- 2MASS Full Survey Image Atlas
- Short Name:
- 2MASS_Full
- Date:
- 01 Oct 2024
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- Photometric calibration for 2MASS was performed using observations of calibration fields made at regular intervals during each night of survey operations. Measurements of standard stars in the fields were used to derive the photometric zero point offsets as a function of time during each night. Atmospheric extinction coefficients were derived from 2MASS observations made over long periods. 2MASS calibration fields, or tiles, are 1° long in declination and approximately 8.5' wide in right ascension. There are 35 regular survey calibration fields distributed at approximately two hour intervals in right ascension near declinations of approximately -30°, 0° and +30°. An additional five calibration fields were defined in and around the Large and Small Magellanic Clouds to support the deep observation (6x) campaign towards the end of survey operations. Calibration scan Atlas Images, and Point and Extended Source Working Databases (Cal-PSWDB and Cal-XSWDB), analogous to those from the main survey, were produced from the calibration scan pipeline data reduction.
- ID:
- ivo://irsa.ipac/2MASS/Images/Sixxfull
- Title:
- 2MASS Long Exposure (6x) Full Survey Image Atlas
- Short Name:
- 2MASS_Sixxfull
- Date:
- 01 Oct 2024
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- During the final months of 2MASS observatory operations, a campaign of targeted "long exposure" observations was carried out during times when no previously unscanned parts of the sky were available for the main survey. These observations used the same freeze-frame scanning technique employed for the survey, but with READ2-READ1 exposures six times longer than was used for normal survey observations (hence they are referred to as "6x" observations). The 2MASS 6x measurements were intended to probe ~1 magnitude deeper than the main survey in unconfused regions. Approximately 590 deg2 of sky distributed in 30 targeted regions were scanned at least once using the long exposures. Most of this area is concentrated in two large, comprehensive surveys of the Large and Small Magellanic Clouds, 383 deg2 and 127 deg2, respectively. Twenty-eight additional smaller fields were mapped in the 6x mode from both observatories, covering targets that include the Pleiades open cluster, galactic star formation complexes, M31, nearby galaxy clusters and the Lockman Hole.
- ID:
- ivo://irsa.ipac/2MASS/Images/Sixxcat
- Title:
- 2MASS Long Exposure (6x) Image Atlas
- Short Name:
- 2MASS_Sixxcat
- Date:
- 01 Oct 2024
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- During the final months of 2MASS observatory operations, a campaign of targeted "long exposure" observations was carried out during times when no previously unscanned parts of the sky were available for the main survey. These observations used the same freeze-frame scanning technique employed for the survey, but with READ2-READ1 exposures six times longer than was used for normal survey observations (hence they are referred to as "6x" observations). The 2MASS 6x measurements were intended to probe ~1 magnitude deeper than the main survey in unconfused regions. Approximately 590 deg2 of sky distributed in 30 targeted regions were scanned at least once using the long exposures. Most of this area is concentrated in two large, comprehensive surveys of the Large and Small Magellanic Clouds, 383 deg2 and 127 deg2, respectively. Twenty-eight additional smaller fields were mapped in the 6x mode from both observatories, covering targets that include the Pleiades open cluster, galactic star formation complexes, M31, nearby galaxy clusters and the Lockman Hole.
- ID:
- ivo://irsa.ipac/Herschel/Images/MESS
- Title:
- Mass-loss of Evolved StarS
- Short Name:
- MESS
- Date:
- 27 Oct 2022 19:00:00
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- Herschel data from the "Mass-loss of Evolved StarS" (MESS) Guaranteed-Time Key Program are available here. IRSA is serving the MESS PACS imaging of 108 evolved stars. This is Herschel program KPGT_mgroen01_1. The sample of AGB stars has been selected to cover all chemical types (M-, S-, C-stars), variability types (irregular, semi-regular, Miras) and periods, and mass-loss rates. Stars have been selected to have high IRAS fluxes and low background levels.
