Chandra Observations of Cygnus A: Magnetic Field Strengths in the Hot Spots of a Radio Galaxy

摘要: We report X-ray observations of the powerful radio galaxy Cygnus A with Chandra X-Ray Observatory. This Letter focuses on hot spots, all four which are detected in X-rays a very similar morphology to their structure. spectra have been obtained for two brighter spots (A and D). Both well described by power law photon index Γ = 1.8 ± 0.2 absorbed Galactic column direction A. Thermal models require too high gas densities may be ruled out. The images strongly support synchrotron self-Compton emission, as proposed Harris, Carilli, & Perley basis ROSAT imaging observations. Such indicate that magnetic field each is 1.5 × 10^(-4) G, an uncertainty few tens percent. value close equipartition strengths assuming no protons present. possibility radiation briefly discussed but not favored. speculate production γ ~ 107 electrons necessary from inhibited when external density high, case within cooling flow.