J1432+158: the most distant giant quasar

Abstract

We present low-frequency, GMRT (Giant Metrewave Radio Telescope) observations at 333 and 617 MHz of the most-distant giant quasar, J1432+158, which is at a redshift of 1.005. The radio source has a total angular extent of 168 arcsec, corresponding to a projected linear size of 1.35 Mpc. This makes it presently the largest single object observed beyond a redshift of one. The objectives of the GMRT observations were to investigate the possibility of detecting a bridge of emission at low frequencies, which may be suppressed due to inverse-Compton losses against the cosmic microwave background radiation. We detect a jet-like structure connecting the core to the western hotspot, while the eastern hotspot is found to be largely tail-less with no significant bridge emission. The estimated life-time for the radiating electrons in the tail of the western lobe appears smaller than the travel time of the radiating particles from the hotspot, suggesting either in-situ acceleration or dissipation of energy by the jet at this location. The pressure of the intergalactic medium at $z\sim 1$ estimated from the minimum energy density calculations appears to be marginally lower than the value extrapolated from nearby giant radio galaxies.

4 pages, 3 figures, 1 table, accepted for publication in MNRAS Letters

References in corpus (7)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• The Nature and Evolution of Classical Double Radio Sources from Complete Samples
• Giant Radio Sources
• A new sample of giant radio galaxies from the WENSS survey: I - Sample definition, selection effects and first results
• The new sample of Giant radio sources: I. Radio imaging, optical identification and spectroscopy of selected candidates
• On the cosmological evolution of the FRII radio source population
• A radio and optical study of Molonglo radio sources

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