Deep GMRT 150-MHz observations of the LBDS-Lynx region: ultrasteep spectrum radio sources

@article{IshwaraChandra2010DeepG1,
  title={Deep GMRT 150-MHz observations of the LBDS-Lynx region: ultrasteep spectrum radio sources},
  author={C. H. Ishwara-Chandra and Sandeep Kumar Sirothia and Yogesh G. Wadadekar and S. Pal and Ruby J. Wright International Centre for Radio Astronomy Research and Pune and India. and Inter-University Centre for Astronomy and Astrophysics and International Centre for Radio Astronomy Research and University of Western Australia and School of Earth and Space Exploration and Arizona State University Usa},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2010},
  volume={405},
  pages={436-446}
}
It has been known for nearly three decades that high-redshift radio galaxies exhibit steep radio spectra, and hence ultrasteep spectrum radio sources provide candidates for high-redshift radio galaxies. Nearly all radio galaxies with z > 3 have been found using this redshift–spectral index correlation. We have started a programme with the Giant Metrewave Radio Telescope (GMRT) to exploit this correlation at flux density levels about 10 to 100 times deeper than the known high-redshift radio… Expand
High-Redshift Radio Galaxies from Deep Fields
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At the faintest radio flux densities ( S 1.4 < 10 mJy), conflicting results have arisen regarding whether there is a flattening of the average spectral index between a low radio frequency (325 or 610Expand
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Giant radio galaxies (GRGs) are a subclass of radio galaxies, which have grown to megaparsec scales. GRGs are much rarer than normal-sized radio galaxies (<0.7 Mpc) and the reason for their giganticExpand
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We report the discovery of the most distant radio galaxy to date, TGSS1530 at a redshift of $z=5.72$ close to the presumed end of the Epoch of Reionisation. The radio galaxy was selected from theExpand
Radio spectral index from NVSS and TGSS
  • P. Tiwari
  • Physics
  • Research in Astronomy and Astrophysics
  • 2019
We extract the radio spectral index, $\alpha$, from 541,195 common sources observed in the 150 MHz TIFR GMRT Sky Survey (TGSS) and the 1.4 GHz NRAO VLA Sky Survey (NVSS). This large common sourceExpand
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