A ROSAT HRI STUDY OF THE INTERACTION OF THE X-RAY-EMITTING GAS AND RADIO LOBES OF NGC-1275

A high spatial resolution ROSA T image of NGC 1275 in the centre of th e Perseus cluster of galaxies shows for the first time clear evidence for the interaction of the relativistic particles in the radio lobes w ith the X-ray-emitting intracluster plasma. The thermal plasma is disp laced by the inner parts of the radio lobes, causing a significant dec rease of the X-ray surface brightness in those regions. The equipartit ion pressure in the radio lobes is somewhat less than the pressure in the surrounding intracluster medium unless a high ratio of relativisti c protons to electrons is assumed.