Oral Presentation
Probing the Environments of Giant Radio Galaxies
Presenter: Ting-Wen Lan (UCSC)
Giant radio galaxies (GRGs) are a rare population of radio galaxies, having enormous radio structures with jets/lobes spanning beyond 1 Mpc scales. While they have been detected for three decades, the origin of such radio structures is still poorly understood. One hypothesis is that GRGs tend to live in low density environments and, therefore, the radio jets/lobes from supermassive black holes can propagate into such a large scale without encountering the intergalactic medium. In this talk, I will show the latest results which challenge this hypothesis. I will show that by cross-correlating about ~100 GRGs identified from the LORAR survey and photometric galaxies detected by the DESI Legacy Imaging Surveys, one can investigate the GRG environments traced by surrounding galaxies. Our results show that the properties of galaxies around GRGs are similar with that around the control samples, demonstrating that external galaxy environments are not the primary driver of the giant radio structures.