  I propose a model for the formation of slow-massive-wide (SMW) jets by
accretion disks around compact objects. This study is motivated by claims for
the existence of SMW jets in some astrophysical objects such as in planetary
nebulae (PNs) and in some active galactic nuclei in galaxies and in cooling
flow clusters. In this model the energy still comes from accretion onto a
compact object. The accretion disk launches two opposite jets with velocity of
the order of the escape velocity from the accreting object and with mass
outflow rate of ~1-20% of the accretion rate as in most popular models for jet
launching; in the present model these are termed fast-first-stage (FFS) jets.
However, the FFS jets encounter surrounding gas that originates in the mass
accretion process, and are terminated by strong shocks close to their origin.
Two hot bubbles are formed. These bubbles accelerate the surrounding gas to
form two SMW jets that are more massive and slower than the FFS jets. There are
two conditions for this mechanism to work. Firstly, the surrounding gas should
be massive enough to block the free expansion of the FFS jets. Most efficiently
this condition is achieved when the surrounding gas is replenished. Secondly,
the radiative energy losses must be small.
