Talk title and abstract:
Galaxies
and
Dark
Matter:
Cosmology,
Correlations,
and
Conundrums
I
will
begin
this
talk
with
an
overview
of
galaxy-galaxy
lensing
and
how
it
informs
us
about
the
connection
between
galaxies
and
their
dark
matter
halos.
I
will
then
present
a
variety
of
new
results
in
this
field.
First,
I
will
discuss
the
“lensing
is
low”
effect
whereby
the
lensing
signal
around
massive
galaxies
has
a
lower
amplitude
than
predicted
based
on
the
galaxy
auto-correlation
function
from
BOSS.
I
will
present
some
new
updates
on
this
topic
and
discuss
the
cosmological
implications
of
this
effect.
I
will
further
present
“Lensing
without
Borders”,
an
inter
survey
collaborative
effort
to
empirically
test
the
accuracy
of
galaxy-galaxy
lensing
measurements
in
current
day
surveys.
I
will
also
present
new
results
suggesting
that
the
light
from
central
galaxies
is
a
much
better
tracer
of
halo
mass
than
previously
recognized
and
I
will
discuss
how
this
effect
might
be
used
to
improve
optical
cluster
finding
algorithms.
Finally,
I
will
present
the
Merian
survey:
a
new
program
that
will
use
60
nights
on
the
Blanco
telescope
and
two
custom
made
filters
to
detect
100,000
dwarf
galaxies
and
measure
their
halo
masses
via
gravitational
lensing.
Would you like to join this Zoom seminar? Please email Donna Hayes.