Nicole Nesvadba, directrice de recherche at the CNRS, is an expert in galaxy evolution based at the Laboratoire Lagrange at the Observatoire de la
Talk Title and Abstract
How
do
AGN
suppress
star
formation
in
galaxies?
How
do
supermassive
black
holes
suppress
star
formation
in
their
host
galaxies?
This
question
is
at
the
heart
of
the
AGN
feedback
hypothesis,
and
is
still
unanswered
after
two
decades
of
intense
observational
and
theoretical
work.
Most
studies
focus
on
gas
removal
in
the
host
galaxies
of
very
powerful
AGN
as
a
main
feedback
mode,
however,
observations
clearly
show
that
outflows
alone
are
insufficient
to
understand
AGN
feedback.
Meanwhile,
alternative
scenarios
do
exist
which
even
challenge
the
basic
assumption
of
a
physical
connection
between
the
AGN
energy
output
and
low
star
formation
rates
in
galaxies.
As
a
consequence,
in
spite
of
the
current
popularity
of
the
AGN
feedback
hypothesis,
its
central
prediction
--
the
direct
physical
link
between
the
energy
injection
by
the
AGN
and
star
formation
--
remains
a
subject
of
considerable
controversy.
In
this
talk,
I
will
discuss
the
observational
and
theoretical
evidence
that
AGN
do
impact
star
formation
in
their
host
galaxies,
within
a
scenario
that
includes
outflows
as
well
as
turbulence
induced
by
the
deposition
of
AGN
energy
in
the
surrounding
gas.
I
will
focus
on
radio
AGN
activity
--
often
considered
a
rare
phenomenon,
but
actually
ubiquitous
in
the
cores
of
massive
galaxies
with
Mstellar
>=
10**11
Msun
--
which
provides
us
with
a
particularly
clean
environment
to
investigate
the
distribution
of
AGN
kinetic
energy
in
the
surrounding
multiphase
gas,
and
its
impact
on
star
formation.
I
will
also
illustrate
how
detailed
observations
of
the
gas
and
stellar
content
in
massive
galaxies
combined
with
hydrodynamic
simulations
can
pave
the
way
towards
a
physical
understanding
of
the
energy
transfer
that
is
at
the
core
of
the
AGN
feedback
hypothesis.
Would you like to join this Zoom seminar? Please email WCA.