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arXiv · 0910.3021

Chandra Observations of the Radio Galaxy 3C 445 and the Hotspot X-ray Emission Mechanism

Eric S. Perlman·Markos Georganopoulos·Emily M. May·Demosthenes Kazanas
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Abstract

We present new {\it Chandra} observations of the radio galaxy 3C 445, centered on its southern radio hotspot. Our observations detect X-ray emission displaced upstream and to the west of the radio-optical hotspot. Attempting to reproduce both the observed spectral energy distribution (SED) and the displacement, excludes all one zone models. Modeling of the radio-optical hotspot spectrum suggests that the electron distribution has a low energy cutoff or break approximately at the proton rest mass energy. The X-rays could be due to external Compton scattering of the cosmic microwave background (EC/CMB) coming from the fast (Lorentz factor $\Gamma\approx 4$) part of a decelerating flow, but this requires a small angle between the jet velocity and the observer's line of sight ($\theta\approx 14^{\circ}$). Alternatively, the X-ray emission can be synchrotron from a separate population of electrons. This last interpretation does not require the X-ray emission to be beamed.

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Eric S. Perlman, Markos Georganopoulos, Emily M. May, Demosthenes Kazanas. 2009-10-16. Chandra Observations of the Radio Galaxy 3C 445 and the Hotspot X-ray Emission Mechanism. https://doi.org/10.1088/0004-637x%2F708%2F1%2F1

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