Abstract:
We investigate a relativistic fluid jet driven by radiation from a shocked accretion disc around
a non-rotating black hole approximated by Paczynski–Wiita potential. The sub-Keplerian and
Keplerian accretion rates control the shock location and therefore, the radiation field around the
accretion disc.We compute the radiative moments with full special relativistic transformation.
The effect of a fraction of radiation absorbed by the black hole has been approximated, over
and above the special relativistic transformations.We show that the radiative moments around
a supermassive black hole are different compared to that around a stellar mass black hole.
We show that the terminal speed of jets increases with the mass accretion rates, synchrotron
emission of the accretion disc, and reduction of proton fraction of the flow composition. To
obtain relativistic terminal velocities of jets, both thermal and radiative driving are important.
We show for very high accretion rates and pair dominated flow, jets around supermassive black
holes are truly ultrarelativistic, while for jets around stellar mass black holes, terminal Lorentz
factor of about 10 is achievable.
