Unveiling New Giant Radio Quasars from the TGSS Sky and Their Large-scale Environment

Abstract Giant radio quasars (GRQs) are radiatively efficient radio-loud active galactic nuclei that propel large-scale radio jets with projected lengths of more than 0.7 Mpc. We report the discovery of 53 new GRQs within a redshift range of 0.14–2.38, as well as 316 new nongiant extended radio quasars (NGERQs) within a redshift range of 0.037–3.356, from the TIFR GMRT Sky Survey Alternative Data Release 1. The projected lengths of the new GRQs range from 0.7 to ∼2.2 Mpc, and the projected lengths of the new NGERQs range from 67 to 695 kpc. We found that the spectral indices of GRQs are statistically similar to those of NGERQs. We have also investigated the large-scale environmental and jet asymmetry properties of the combined sample, which includes new sources and previously discovered extended radio quasars (ERQs) from the literature. The results indicate that at least 13% of GRQs and 14% of NGERQs in the sample are located in galaxy groups and cluster environments. Similar lower-bound percentages reside near large-scale filamentary structures, with median projected distances of 5.9 and 4.3 Mpc from their respective host quasars. At the current survey noise levels, we find that the projected lengths of ERQs in our sample at z ≥ 1 are smaller than those at z < 1. Furthermore, GRQs at z ≥ 1 exhibit greater arm-length asymmetry compared to NGERQs, which may be attributed to an asymmetric environment.