Title and Abstract for James’s talk:
Superbubbles,
Galactic
Winds
and
the
limits
of
Supernovae
on
Galactic
Scales
Different
modes
of
stellar
feedback
play
different
roles
within
galaxies.
We
study
the
role
of
supernovae,
an
historically
popular
choice,
on
the
evolution
of
galaxies
and
their
stellar
content.
We
argue
that
prior
work
has
modeled
supernovae
poorly
by
ignoring
stellar
clustering
and
also
the
key
physics
of
conduction
that
governs
hot
gas
evolution.
Clustered
supernovae
create
superbubbles,
kpc-scale
feedback
events
that
can
drive
strong
galactic
winds.
We
show
that
superbubbles
can
be
modeled
via
first
principles
simulations
without
resorting
to
common
numerical
tricks
that
may
lead
to
incorrect
results.
In
particular,
we
find
that
entropy
plays
an
important
role
in
generating
winds.
Galaxies
with
superbubble
feedback
strongly
regulate
their
star
formation
and
global
baryon
budget.
These
simulated
galaxies
match
disk
galaxy
observations
very
well.
However,
there
are
limits
--
supernovae
cannot
explain
the
regulation
of
star
formation
in
massive
galaxies.