Browsing by Author "Prescott, M"

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    An investigation into the morphology of radio sources
    (University of Western Cape, 2021) Ella, Moloko Malebo; Prescott, M; Santos, M
    Radio galaxies are some of the most unusual and powerful objects in the Universe and are therefore vital for so many reasons. Studies of Radio-Loud Active Galactic Nuclei (AGN) gives us the potential to enhance our understanding of the key processes leading to the ejection of material, connection to the central engine and how the jets are launched. Besides, the energetic input of these sources is thought to have an impact in the star formation history and properties of the ISM and ICM; thus by studying them, we can improve our understanding of their formation, evolution and their environment.
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    MIGHTEE: Are giant radio galaxies more common than we thought?
    (Oxford University Press, 2021) Prescott, M; Delhaize, J; Heywood, I
    We report the discovery of two new giant radio galaxies (GRGs) using the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey. Both GRGs were found within a ∼}1\, deg2 region inside the COSMOS field. They have redshifts of z = 0.1656 and z = 0.3363 and physical sizes of 2.4 and 2.0 Mpc, respectively. Only the cores of these GRGs were clearly visible in previous high-resolution Very Large Array observations, since the diffuse emission of the lobes was resolved out. However, the excellent sensitivity and uv coverage of the new MeerKAT telescope allowed this diffuse emission to be detected. The GRGs occupy an unpopulated region of radio power - size parameter space. Based on a recent estimate of the GRG number density, the probability of finding two or more GRGs with such large sizes at z < 0.4 in a ∼}1\, deg2 field is only 2.7 × 10-6, assuming Poisson statistics. This supports the hypothesis that the prevalence of GRGs has been significantly underestimated in the past due to limited sensitivity to low surface brightness emission.