Astrophysics Science Division Colloquium Series
Schedule: September 2008
ASD Colloquia are Tuesdays at 3:45 pm (Meet the Speaker at 3:30 pm) in Bldg 21, Room 183
unless otherwise noted.
How to Publish in Nature
Leslie Sage
Nature Magazine
Tuesday, September 2, 2008
Abstract
TBD
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Exploring Fundamental Physics with Astrophysical Techniques
Christopher Stubbs
Harvard University
Tuesday, September 9, 2008
Abstract
The best evidence we have for physics beyond the standard model comes from
astrophysical observation: Dark Energy, Dark Matter, and even the abundance
of matter over antimatter are each indications of shortcomings in our
understanding of basic physics. I will describe our efforts to understand
the nature of the Dark Energy, and why this particular problem merits our
collective attention. I'll also present the status of PanSTARRS and LSST,
two ambitious ground-based optical systems that will provide new
capabilities for studying diverse topics in astronomy and astrophysics.
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Inflation, Gravity Waves, and the Cosmic Microwave Background
Alan Kogut
GSFC
Tuesday, September 16, 2008
Abstract
The polarization of the cosmic microwave background contains a contribution from gravity waves excited during the epoch of inflation, shortly after
the Big Bang. A positive detection of this signal would have extraordinary consequences for both cosmology and physics: not only would it establish
inflation as a physical reality, but it would also provide a model-independent determination of the relevant energy scale. I will present the
scientific motivation behind measurements of the CMB polarization and discuss how recent experimental progress could lead to a detection of the
inflationary signal in the not-very-distant future.
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Spitzer Survey of the Large Magellanic Cloud, Surveying the Agents of a Galaxy's Evolution (SAGE)
Margaret Meixner
Space Telescope Science Institute
Tuesday, September 23, 2008
Abstract
The recycling of matter between the interstellar medium (ISM) and stars are key evolutionary drivers of a galaxy's visible matter. The SAGE team is
performing a Spitzer Legacy imaging survey of the Large Magellanic Cloud (LMC), using the IRAC (3.6, 4.5, 5.8 and 8 microns) and MIPS (24, 70, and 160
microns) instruments on board Spitzer. The Spitzer wavelengths provide a sensitive probe of circumstellar and interstellar dust and hence, allows us
to study the physical processes of the ISM, the formation of new stars and the injection of mass by evolved stars and their relationships on the
galaxy-wide scale of the LMC. Due to its proximity, favorable viewing angle, multi-wavelength information, and measured tidal interactions with the
Milky Way (MW) and Small Magellanic Cloud (SMC), the LMC is uniquely suited for surveying the agents of a galaxy's evolution (SAGE), the ISM and
stars. Our uniform and unbiased survey of the LMC (7x7 degrees) will have much better wavelength coverage, up to ~1000 times better point source
sensitivity and ~11 times better angular resolution than previous IR surveys. SAGE will reveal over 6 million sources including ~150,000 evolved
stars, ~50,000 young stellar objects and the diffuse ISM with column densities >1.2x10^{21} H/cm^2. The diffuse IR emission in the LMC can be
associated with individual gas/dust clouds, thereby permitting unique studies of dust processes in the ISM. SAGE's complete census of newly formed
stars with masses >1-3 Msun will reveal whether tidally-triggered star formation events in the LMC are sustained or short-lived. SAGE's complete
census of evolved stars with mass loss rates >1x10^{-8} Msun/yr will quantitatively measure the rate at which evolved stars inject mass into the ISM.
In this talk, I will present an overview of the SAGE survey including preliminary results on ISM, star formation and evolved stars.
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A wide-field view of the TeV sky: The results of the Milagro Experiment
Andy Smith
University of Maryland
Tuesday, September 30, 2008
Abstract
TBA
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Randall Smith
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