Powerful yet lonely: 3C 297 a strong radio source without close companions

Like similar sources of the 3CR catalog, 3C 297 (z=1.408) has the typical characteristics of a brightest cluster galaxy (BCG). Indeed, new and archival Chandra observations of 3C 297 and its environment have unveiled a cluster-like extended X-ray halo, and a bright X-ray knot related to the radio jet emanating from 3C 297. Yet, in HST images 3C 297 appears isolated in the field, and no galaxies at the same redshift are known in the literature. Using the Gemini Multi-Object Spectrograph (GMOS), we conducted a redshift survey for 43 targets in the field of 3C 297. Remarkably, none of the galaxies for which a new redshift is derived using the new Gemini data is at the same distance as 3C 297.

This work was supported by Chandra grant GO1-22112B.