Understand
X-ray emission associated with the west lobe of the giant radio galaxy, 3C 236, was investigated with the Suzaku observatory, to evaluate the energetics in the lobe.
- After removing contamination from X-ray sources detected with Chandra and subtracting the X-ray and non-X-ray backgrounds, the Suzaku spectrum from the lobe was reproduced by a power-low model with a photon index of $\Gamma = 2.23_{-0.38-0.12}^{+0.44+0.14}$ where the first and second errors represent the statistical and systematic ones, respectively.
- Within the errors, the X-ray index was consistent with the radio synchrotron one, $\Gamma_{\rm R} = 1.74 \pm 0.07$, estimated in the 326 -- 2695 MHz range.
- This agreement supports that the X-ray emission is attributed to the inverse-Compton (IC) radiation from the synchrotron electrons filling the lobe, where the cosmic microwave background photons are up-scattered.