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start [2017/05/21 10:51] – [Description] intemastart [2024/01/19 12:05] (current) – [Publications involving TGSS ADR] intema
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 ~~NOTOC~~ ~~NOTOC~~
  
-{{keywords>astronomy,radio,interferometry,galaxy,galaxies,agn,gmrt,giant,metrewave,telescope,tgss,adr,lofar,mwa,ska,ncra,nrao,astron,leiden,oxford,india,huib,intema,preshanth,jagannathan,kunal,mooley,dale,frail,pulsars,150,MHz,megahertz,low,frequency,ionosphere,spam,sources,catalogs,aladin,hips,rms,sensitivity,mjy,vo,virtual,observatory,counts,steep,spectral,index,merging,galaxy,clusters,haloes,halos,relics,interactive,data,products,antenna,dish}}+{{htmlmetatags>metatag-keywords=(keywords>astronomy,radio,interferometry,galaxy,galaxies,agn,gmrt,giant,metrewave,telescope,tgss,adr,lofar,mwa,ska,ncra,nrao,astron,leiden,oxford,india,huib,intema,preshanth,jagannathan,kunal,mooley,dale,frail,pulsars,150,MHz,megahertz,low,frequency,ionosphere,spam,sources,catalogs,aladin,hips,rms,sensitivity,mjy,vo,virtual,observatory,counts,steep,spectral,index,merging,galaxy,clusters,haloes,halos,relics,interactive,data,products,antenna,dish)}}
  
 {{ :tgssadr_front_07Mar2016.jpg?nolink }} {{ :tgssadr_front_07Mar2016.jpg?nolink }}
  
-=== Science team: Huib T. Intema (Leiden/NRAO), Preshanth Jagannathan (NRAO/UCT), Kunal P. Mooley (Oxford) & Dale A. Frail (NRAO) ===+===Science team=== 
 +[[http://www.intema.nl/doku.php?id=huibintema|Huib T. Intema (Leiden/NRAO)]][[http://www.aoc.nrao.edu/~pjaganna/|Preshanth Jagannathan (NRAO/UCT)]][[http://www.astro.caltech.edu/~kunal/|Kunal P. Mooley (Oxford/NRAO)]] [[http://www.aoc.nrao.edu/~dfrail/|Dale A. Frail (NRAO)]]
  
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 ===== Description ===== ===== Description =====
  
-The [[http://gmrt.ncra.tifr.res.in/|Giant Metrewave Radio Telescope (GMRT)]] was used to survey the radio sky at 150 MHz between 2010 and 2012. To date, the data collected by the [[http://tgss.ncra.tifr.res.in/|TIFR GMRT Sky Survey (TGSS)]] project team remained largely unpublished within the scope of that project. We independently reprocessed the TGSS data using the [[https://safe.nrao.edu/wiki/bin/view/Main/HuibIntemaSpam|SPAM pipeline]], which includes corrections for direction-dependent ionospheric phase effects. Our first alternative data release (ADR1) includes continuum stokes I images of 99.5 percent of the radio sky north of -53° DEC (3.6π sr, or 90 percent of the full sky) at a resolution of 25" x 25" north of 19° DEC and 25" x 25" / cos(DEC-19°) south of 19°, and a median noise of 3.5 mJy/beam. The extracted radio source catalog contains positions, flux densities, sizes and more for 0.62 Million sources down to a 7-sigma peak-to-noise threshold. The data processing and products are described in detail in [[http://adsabs.harvard.edu/abs/2017A%26A...598A..78I|Intema et al. (2017)]].+The [[http://gmrt.ncra.tifr.res.in/|Giant Metrewave Radio Telescope (GMRT)]] was used to survey the radio sky at 150 MHz between 2010 and 2012. To date, the data collected by the TIFR GMRT Sky Survey (TGSS) project team remained largely unpublished within the scope of that project. We independently reprocessed the TGSS data using the [[http://www.intema.nl/doku.php?id=huibintemaspampipeline|SPAM pipeline]], which includes corrections for direction-dependent ionospheric phase effects. Our first alternative data release (ADR1) includes continuum stokes I images of 99.5 percent of the radio sky north of -53° DEC (3.6π sr, or 90 percent of the full sky) at a resolution of 25" x 25" north of 19° DEC and 25" x 25" / cos(DEC-19°) south of 19°, and a median noise of 3.5 mJy/beam. The extracted radio source catalog contains positions, flux densities, sizes and more for 0.62 Million sources down to a 7-sigma peak-to-noise threshold. The data processing and products are described in detail in [[http://adsabs.harvard.edu/abs/2017A%26A...598A..78I|Intema et al. (2017)]]. 
 +----- 
 +The TGSS-NVSS spectral index data release page is found [[spidx|here]].
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 News will be posted here and on our [[https://www.facebook.com/TGSSADR/|Facebook page]]. News will be posted here and on our [[https://www.facebook.com/TGSSADR/|Facebook page]].
  
 +   * 22-Aug-2018: Since 1-2 weeks there have been some issues with the VO server where TGSS ADR is hosted. As a result, also NASA SkyView has not been working correctly for TGSS ADR. Please know that the problem is being addressed, and SkyView is expected to properly work again in a matter of days.
 +   * 01-Dec-2017: A special version of TGSS ADR1 has been combined with NVSS to create a spectral index map and catalog of approx. 80 percent of the radio sky. The public data release page is found [[spidx|here]].
    * 15-Nov-2016: The TGSS-based LOFAR Sky Model Creator now has a flux cutoff option to exclude sources below a certain threshold. This can be used to speed up the initial calibration by using fewer model sources.    * 15-Nov-2016: The TGSS-based LOFAR Sky Model Creator now has a flux cutoff option to exclude sources below a certain threshold. This can be used to speed up the initial calibration by using fewer model sources.
    * 14-Oct-2016: The TGSS ADR1 paper is accepted for publication in A&A! The version on arXiv is updated as of today ([[https://arxiv.org/abs/1603.04368|arXiv:1603.04368]])    * 14-Oct-2016: The TGSS ADR1 paper is accepted for publication in A&A! The version on arXiv is updated as of today ([[https://arxiv.org/abs/1603.04368|arXiv:1603.04368]])
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 The TGSS ADR survey products are hosted by the ASTRON virtual observatory (VO) system. This system complies with the VO standard and can be accessed directly by tools like [[http://www.star.bris.ac.uk/~mbt/topcat/|TOPCAT]]. The VO system provides three services, for which web-based interfaces are available: The TGSS ADR survey products are hosted by the ASTRON virtual observatory (VO) system. This system complies with the VO standard and can be accessed directly by tools like [[http://www.star.bris.ac.uk/~mbt/topcat/|TOPCAT]]. The VO system provides three services, for which web-based interfaces are available:
-   * [[http://vo.astron.nl/tgssadr/q_fits/imgs/form|TGSSADR Image Archive]] containing 5336 mosaic images of 5x5 square degrees covering the survey area. +   * [[https://vo.astron.nl/tgssadr/q_fits/imgs/form|TGSSADR Image Archive]] containing 5336 mosaic images of 5x5 square degrees covering the survey area. 
-   * [[http://vo.astron.nl/tgssadr/q_fits/cutout/form|TGSSADR Image Cutout Service]] provides cutout images of up to 1x1 square degrees anywhere in the survey area. +   * [[https://vo.astron.nl/tgssadr/q_fits/cutout/form|TGSSADR Image Cutout Service]] provides cutout images of up to 1x1 square degrees anywhere in the survey area. 
-   * [[http://vo.astron.nl/tgssadr/q/cone/form|TGSSADR Source Catalogue]] provides access to the 0.63 Million radio source catalog extracted from the full survey area.+   * [[https://vo.astron.nl/tgssadr/q/cone/form|TGSSADR Source Catalogue]] provides access to the 0.63 Million radio source catalog extracted from the full survey area.
 The VO service links are given here: The VO service links are given here:
-   * [[http://vo.astron.nl/tgssadr/q/cone/scs.xml|TGSSADR VO Source Cone Search (SCS)]] +   * [[https://vo.astron.nl/tgssadr/q/cone/scs.xml|TGSSADR VO Source Cone Search (SCS)]] 
-   * [[http://vo.astron.nl/tgssadr/q_fits/imgs/siap.xml|TGSSADR VO Simple Image Access (SIA)]]+   * [[https://vo.astron.nl/tgssadr/q_fits/imgs/siap.xml|TGSSADR VO Simple Image Access (SIA)]]
  
 The 5x5 square degree mosaic images that form the basis of TGSS ADR1 are available for direct download [[http://tgssadr.strw.leidenuniv.nl/mosaics/|here]] (5336 FITS images; 32 MB each). Note that there is a factor 3.6(!) redundancy in the sky coverage, mainly to guarantee up to 1x1 square degree cutouts anywhere in the survey area. The 5x5 square degree mosaic images that form the basis of TGSS ADR1 are available for direct download [[http://tgssadr.strw.leidenuniv.nl/mosaics/|here]] (5336 FITS images; 32 MB each). Note that there is a factor 3.6(!) redundancy in the sky coverage, mainly to guarantee up to 1x1 square degree cutouts anywhere in the survey area.
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 <code python> <code python>
 import pyvo as vo import pyvo as vo
-url = 'http://vo.astron.nl/tgssadr/q/cone/scs.xml'+url = 'https://vo.astron.nl/tgssadr/q/cone/scs.xml'
 t = vo.conesearch( url, pos = vo.object2pos( 'NGC 5939' ), radius = 30.0 ) t = vo.conesearch( url, pos = vo.object2pos( 'NGC 5939' ), radius = 30.0 )
 print t.votable print t.votable
 </code> </code>
 +
 +[[https://github.com/aayush3009/TGSS-ADR1-cutouts|Here]] is the github link to a python script written by Aayush Saxena (Leiden) that uses PyVO to get image cutouts.
  
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    * Alternatively, [[http://tgssadr.strw.leidenuniv.nl/catalogs/TGSSADR1_7sigma_catalog.fits|http://tgssadr.strw.leidenuniv.nl/catalogs/TGSSADR1_7sigma_catalog.fits]] to load the TGSS ADR catalog, but this may slow down the Aladin display significantly.    * Alternatively, [[http://tgssadr.strw.leidenuniv.nl/catalogs/TGSSADR1_7sigma_catalog.fits|http://tgssadr.strw.leidenuniv.nl/catalogs/TGSSADR1_7sigma_catalog.fits]] to load the TGSS ADR catalog, but this may slow down the Aladin display significantly.
  
-Note: When using the Aladin Desktop tool, it keeps a local cache (under $HOME/.aladin/Cache). Ocaisionally we will make changes to the HiPS images or catalog, which we will announce in the news section and on Facebook. For this to work, the local Aladin cache needs to be cleared (deleted)As far as we know, this can only be done by deleting the contents of the cache directory. +Note: When using the Aladin Desktop tool, it keeps a local cache (under $HOME/.aladin/Cache). Occaisionally we will make changes to the HiPS images or catalog, which we will announce in the news section and on Facebook. For this to work, the local Aladin disk cache needs to be cleared. In Aladin, this can be done under Edit->User Preferences.
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 ===== LOFAR Sky Model Creator ===== ===== LOFAR Sky Model Creator =====
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 You can use the TGSS ADR source catalog for generating a BBS-compatible Global Sky Model to calibrate your LOFAR data. Either fill out the form below, or run something like \\ You can use the TGSS ADR source catalog for generating a BBS-compatible Global Sky Model to calibrate your LOFAR data. Either fill out the form below, or run something like \\
-//wget -O GSM.txt <nowiki>'http://tgssadr.strw.leidenuniv.nl/cgi-bin/gsmv3.cgi?coord=3c323&radius=3&unit=deg&deconv=y&cutoff=0.3'</nowiki>+//wget -O GSM.txt <nowiki>'http://tgssadr.strw.leidenuniv.nl/cgi-bin/gsmv4.cgi?coord=3c323&radius=3&unit=deg&deconv=y&cutoff=0.3'</nowiki>
 // //
  
 <html> <html>
-<form name="TGSSGSM" method="POST" action="cgi-bin/gsmv3.cgi">  +<form name="TGSSGSM" method="POST" action="cgi-bin/gsmv4.cgi">  
 Position =  <input type="text" name="coord" /> Position =  <input type="text" name="coord" />
 (NED/Simbad Object or RA,Dec)  (NED/Simbad Object or RA,Dec) 
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   - D.A. Frail, P. Jagannathan, K.P. Mooley, H.T. Intema, 2016 (ApJ in press), [[https://arxiv.org/abs/1606.00449|arXiv:1606.00449]], \\ //Known Pulsars Identified in the GMRT 150 MHz All-Sky Survey//   - D.A. Frail, P. Jagannathan, K.P. Mooley, H.T. Intema, 2016 (ApJ in press), [[https://arxiv.org/abs/1606.00449|arXiv:1606.00449]], \\ //Known Pulsars Identified in the GMRT 150 MHz All-Sky Survey//
   - S.J. Tingay, P.J. Hancock, R.B. Wayth, H. Intema, P. Jagannathan, K. Mooley, 2016 (AAS accepted), [[https://arxiv.org/abs/1606.01761|arXiv:1606.01761]] \\ //A multi-resolution, multi-epoch low radio frequency survey of the Kepler K2 mission Campaign 1 field//   - S.J. Tingay, P.J. Hancock, R.B. Wayth, H. Intema, P. Jagannathan, K. Mooley, 2016 (AAS accepted), [[https://arxiv.org/abs/1606.01761|arXiv:1606.01761]] \\ //A multi-resolution, multi-epoch low radio frequency survey of the Kepler K2 mission Campaign 1 field//
 +
 +... and many many more.
  
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 ===== Acknowledgements ===== ===== Acknowledgements =====
  
-If you are using the TGSS ADR survey products for your research, that's great! Please acknowledge our service to the astronomical community by adding this reference (//Intema et al. 2016submitted to A&A; arXiv:1603.04368//) in your publication. +If you are using the TGSS ADR survey products for your research, that's great! Please acknowledge our service to the astronomical community by adding this reference ([[http://adsabs.harvard.edu/abs/2017A%26A...598A..78I|Intema et al. 2017, A&A, 598, A78]]) in your publication. 
  
 Please also add the standard GMRT acknowledgement: //We thank the staff of the GMRT that made these observations possible. GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research.// Please also add the standard GMRT acknowledgement: //We thank the staff of the GMRT that made these observations possible. GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research.//
start.1495363874.txt.gz · Last modified: 2017/05/21 10:51 by intema