3C 401 is a powerful radio galaxy located in the constellation Draco. It is near the center of a rich cluster of galaxies and dominates the cluster. That is, it is the type-cD galaxy of its cluster. It has a double nucleus, indicating that it is merging with another galaxy.^[1]

3C 401 is classified as a Faranoff and Riley class II radio source (FR II),^[2] but has characteristics of both types of sources. FR II radio sources are brightest at the ends of their radio lobes while FR I sources are brightest toward their centers. 3C 401 has hot spots at the ends of its two extended radio lobes, but also has a bright one-sided jet like a FR I source.^[3] The spectra of this jet is also intermediate between the spectra of jets in the two types of sources.^[4]

References

sk:3C 401 zh:QSO B1939+605