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Register a new userDiscovery of a suspected giant radio galaxy with the KAT-7 array
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Added by
Sergio Colafrancesco
Publication date
2015
fields
Physics
and research's language is
English
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We detect a new suspected giant radio galaxy (GRG) discovered by KAT-7. The GRG core is identified with the WISE source J013313.50-130330.5, an extragalactic source based on its infrared colors and consistent with a misaligned AGN-type spectrum at $zapprox 0.3$. The multi-$ u$ spectral energy distribution (SED) of the object associated to the GRG core shows a synchrotron peak at $ u approx 10^{14}$ Hz consistent with the SED of a radio galaxy blazar-like core. The angular size of the lobes are $sim 4 ^{prime}$ for the NW lobe and $sim 1.2 ^{prime}$ for the SE lobe, corresponding to projected linear distances of $sim 1078$ kpc and $sim 324$ kpc, respectively. The best-fit parameters for the SED of the GRG core and the value of jet boosting parameter $delta =2$, indicate that the GRG jet has maximum inclination $theta approx 30$ deg with respect to the line of sight, a value obtained for $delta=Gamma$, while the minimum value of $theta$ is not constrained due to the degeneracy existing with the value of Lorentz factor $Gamma$. Given the photometric redshift $z approx 0.3$, this GRG shows a core luminosity of $P_{1.4 GHz} approx 5.52 times 10^{24}$ W Hz$^{-1}$, and a luminosity $P_{1.4 GHz} approx 1.29 times 10^{25}$ W Hz$^{-1}$ for the NW lobe and $P_{1.4 GHz} approx 0.46 times 10^{25}$ W Hz$^{-1}$ for the SE lobe, consistent with the typical GRG luminosities. The radio lobes show a fractional linear polarization $approx 9 %$ consistent with typical values found in other GRG lobes.
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