Using observations from the Chandra X–ray Observatory and Giant Metrewave Radio Telescope , we examine the interaction between the intracluster medium and central radio source in the poor cluster AWM 4 .
In the Chandra observation a small cool core or galactic corona is resolved coincident with the radio core .
This corona is capable of fuelling the active nucleus , but must be inefficiently heated by jet interactions or conduction , possibly precluding a feedback relationship between the radio source and cluster .
A lack of clearly detected X–ray cavities suggests that the radio lobes are only partially filled by relativistic plasma .
We estimate a filling factor of \phi =0.21 ( 3 \sigma upper limit \phi < 0.42 ) for the better constrained east lobe .
We consider the particle population in the jets and lobes , and find that the standard equipartition assumptions predict pressures and ages which agree poorly with X–ray estimates .
Including an electron population extending to low Lorentz factors either reduces ( \gamma _ { min } = 100 ) or removes ( \gamma _ { min } = 10 ) the pressure imbalance between the lobes and their environment .
Pressure balance can also be achieved by entrainment of thermal gas , probably in the first few kiloparsecs of the radio jets .
We estimate the mechanical power output of the radio galaxy , and find it to be marginally capable of balancing radiative cooling .