What MSU Astronomers Will Do with the SOAR

What MSU Astronomers
Will Do
with the
SOAR
Telescope
The laboratory
The rest
of the laboratory
Galactic Structure and Stellar
Astronomy
Timothy
Beers
Bob
Stein
Ed
Brown
The MSU
Astronomy Group
Department of Physics &
Astronomy
Horace
Smith
Astronomical
Instrumentation
Ed Loh
Gene
Capriotti
Extragalactic
Astronomy
Steve
Zepf
Jack
Baldwin
Megan
Donahue
Mark
Voit
The History of our own Galaxy
Star-by-star Archeology
• Growth of galaxies by accretion
• Chemical evolution
• All elements heavier than H and He
were formed by nuclear reactions in
stars
Small Magellanic Cloud
Milky Way
The view from Chile
Large Magellanic Cloud
M31, M32
NGC 205
Timothy Beers:
The “First Star”: HE 0107-5240
[Fe/H] = -5.3
[C/Fe] = +3.9
[N/Fe] = +2.4
Elemental
Abundances in
the Oldest Stars
• Long-lived stars from just after
initial round of star formation
• Found by searches through huge
samples
• Then detailed follow-up
observations with SOAR and
other even larger telescopes
Wavelength 
Galactic orbital
velocity components
as a function of [Fe/H]
[Fe/H]
distributions
in the HK and
HES surveys
Horace Smith:
Variable Stars
Large Magellanic Cloud
• Keys to astronomical distance
scale
• Laboratories for stellar
evolution
• Probes of galactic structure
and history
With SOAR,
variable stars
can be studied
in detail
throughout
the Local
NGC 6822 Group…
The Galactic
bulge includes
many globular
clusters
…and in the bulge of the Milky Way
Interpreting the data.
Our theorists combine physical insight
with detailed simulations.
Ed Brown
High Energy
Astrophysics and
Compact Objects.
•
•
•
What is the structure of
neutron stars?
How does accretion modify this
structure?
How do supernovae work?
Simulation of an offcenter explosion of a
white dwarf star.
Distribution of isotopes
formed in the explosion,
a short time after
ignition.
X-rays from the surface of
an accreting neutron star,
detected by Chandra.
Interpreting the Data
Our theorists combine physical insight
with detailed simulations
Bob Stein
The Outer Layers
of the Sun
• Convection in the Sun’s
atmosphere
• The role of magnetic fields
• Solar Oscillations
• Understanding what the
Sun’s continuous
pulsations tell us about
its inner structure
Numerical model
of gas flow inside
a convection cell
Model of a
downdraft in the
Sun’s outer layers
What is the Universe
Made Of ?
We know these are there,
but we don’t know what
they are
• 73% Dark Energy
• 22% Dark Matter
• 4% Normal Matter
(using E = mc2)
This is the only part we see
Ed Loh:
Size of Universe 
The Properties of Dark
Energy
• Spartan Infrared Camera on SOAR:
Accelerating
Universe.
Supernovae
xxx
Now
Time 
• Dark Energy causes acceleration
of expansion of Universe:
• Discovered from unexpected
faintness of distant supernovae
• Will measure Supernovae at still
greater distances
• Are they really “standard candles”?
• Dimming by dust?
• Luminosity evolution with lookback time?
• Relationship between density and
pressure of Dark Energy
• Usual assumption: Einstein’s
cosmological constant
• But we don’t know…
• Measuring this relation will
help identify what Dark
Energy really is
Steve Zepf:
Looking Back to the Time
of Galaxy Formation
• Galaxies form in the presence of
Dark Matter
• Galaxies are where star and
planet formation occurs
Bottom-up structure formation.
• Huge light-travel times  we can
see galaxies being assembled from
smaller units, over 13 billion years
ago
Use globular clusters to reconstruct the
formation history of nearby galaxies
Jack Baldwin:
Quasars trace the evolution of massive
galaxies.
Quasars:
Luminous
quasars visible at
huge distances
 can study
galaxies at very
large lookback
times
Gas spiraling into
massive central
black hole converts
gravitational energy
into huge amounts
of light
But also…
A nearby mini-quasar
NGC 3393
Black Hole
Expanding gas
bubbles
Megan Donahue:
Mark Voit:
Giant Clusters of Galaxies
• Recently formed  test details of
“bottom-up” formation scenario
• Evolution of cluster population
 sensitive probe of Dark Matter
and Dark Energy
• Best “fair sample” of matter
content of Universe
• Dark vs. normal matter
“Gravitational lensing” of
distant background
galaxies measures total
mass of foreground cluster
Hercules Cluster
What we study
• Dark Energy
• Type Ia supernovae
• Galaxy clusters
• Dark Matter
Astronomy
• Evolution of structures
• Galaxies
• Galaxy clusters
• Chemical Evolution
• Stellar processes
• Elemental abundances
in ancient stars
• Evolution of stellar
populations
High Energy
Physics
Nuclear
Physics
SOAR
MSU’s Laboratory for Astronomical Discovery