Jittering jets by negative angular momentum feedback in cooling flows
  I apply the jittering jets in cooling flow scenario to explain the
perpendicular to each other and almost coeval two pairs of bubbles in the
cooling flow galaxy cluster RBS 797, and conclude that the interaction of the
jets with the cold dense clumps that feed the supermassive black hole (SMBH)
takes place in the zone where the gravitational influence of the SMBH and that
of the cluster are about equal. According to the jittering jets in cooling flow
scenario jets uplift and entrain cold and dense clumps, impart the clumps
velocity perpendicular to the original jets' direction, and `drop' them closer
to the jets' axis. The angular momentum of these clumps is at a very high angle
to the original jets' axis. When these clumps feed the SMBH in the next
outburst the new jets' axis is at a high angle to the axis of the first pair of
jets. I apply this scenario to recent observations that show the two
perpendicular pairs of bubbles in RBS 797 to have a small age difference of
<10Myr, and conclude that the jets-clumps interaction takes place in a distance
of about ~10-100 pc from the SMBH. Interestingly, in this zone the escape
velocity from the SMBH is about equal to the sound speed of the intracluster
medium (ICM). I discuss the implications of this finding.
