2001/01/24 by Christopher P. O'Dea, C. P. O’Dea, Anton M. Koekemoer +11 · 1 citation
Medicine · Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Medicine #Radio Astronomy Observations and Technology #astro-ph
paper · pdf · doi:10.1086/319953
arxiv created 2001/01/24 · openalex publication_date 2001/04/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Astronomical Journal, in press We present new HST STIS/MAMA near-UV images and archival WFPC2 V and R band images which reveal the presence of four star forming regions in an arc along the edge of the dust lane in the giant (4 Mpc) radio galaxy 3C 236. Two of the star forming regions are relatively young with ages of order ∼ 10 7 yr, while the other two are older with ages of order ∼ 10 8 − 10 9 yr which is comparable to the estimated age of the giant radio source. Based on dynamical and spectral aging arguments, we suggest that the fuel supply to the AGN was interrupted for ∼ 10 7 yr and has now been restored, resulting in the formation of the inner 2 kpc scale radio source. This time scale is similar to that of the age of the youngest of the star forming regions. We suggest that the transport of gas in the disk is non-steady and that this produces both the multiple episodes of star formation in the disk as well as the multiple epochs of radio source activity. If the inner radio source and the youngest star forming region