Authors: M.L. Lister and K.I. Kellermann
Abstract:
Quasars and AGN are the most powerful long lived phenomena in the
Universe.Although, it has been a half a century since their discovery,
and even longer since the recognition of radio galaxies, many questions
remain unanswered.These include:
a)Although all quasars probably contain a super massive black hole to
supply the power needed to support their extraordinary optical and
infrared luminosity, why are only a small fraction of quasars strong
radio sources?
b)What is the radio emission mechanism in radio quiet quasars?
c)Do the radio loud and radio quiet quasar luminosity functions evolve
differently?
d)What is the role of quasars and AGN in the formation and evolution of
galaxies?Do radio quiet and radio loud quasars play the same role in
galaxy evolution?
e)What is the role of relativistic jets in producing the apparent
excessive radio as well as OIR and gamma-ray luminosity?How are
relativistic jets formed; how are they collimated, and how do they
evolve?What causes the apparent rotation of ejection position angle in
some quasars?What is the relation between the presumably beamed radio
and gamma-ray emission?
f)Are other radiation processes beside incoherent synchrotron radiation
important?
g)What is the contribution, if any, of discrete radio sources to the
observed apparent excess non thermal cosmic radio background radiation?