2015 Ralph B. Baldwin Award Lecture
in Astrophysics and Space Sciences
Please join the Department of Physics
Tuesday, May 5, 2015
to celebrate
Physics Alumnus Dr. Tomasz Biesiadzinski
Recipient of the Ralph B. Baldwin Award
4:00 to 5:00 pm in 340 West Hall
Reception prior to public lecture at 3:30 pm in 337 West Hall
Dr. Biesiadzinski will give a public lecture on his U-M research and discuss
his current work at the SLAC National Accelerator Laboratory.
Unbiasing Cosmological Surveys
Abstract: Large scale observations of the Universe can reveal a great deal about its nature and
evolution. They are particularly necessary to study dark energy, the mysterious source that
drives the accelerating expansion of the Universe. Among these observations are surveys of
galaxies, supernovae and of the millimeter-wave sky. Galaxy and millimeter-wave surveys of the
Sunyaev-Zel'dovich (SZ) effect can be used to trace the distribution of matter back through time
and how it was influenced by dark energy. Similarly, measurements of distances to supernovae
tell us about how the space between them and us changed over time. All of these measurements are made difficult by various physical and instrumental sources of uncertainty and bias.
We studied some of these uncertainties in near-infrared instruments for supernovae
observations and in the joint analysis of optical galaxy and SZ sources in order to eliminate
biases from the measurement of cosmological parameters that describe the Universe.
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The Ralph B. Baldwin Prize in Astrophysics and Space Sciences is annually awarded to a scholar in the fields of
Astronomy, Atmospheric, Oceanic, and Space Science; Chemistry; Physics; or Geology who has received a University
of Michigan Ph.D. during the previous year. This award recognizes excellence in research activities pertaining to
space, its bodies, and relevant physical processes. Recipients have demonstrated original and significant
contributions to their fields as measured in their thesis and scholarly publications. The Ralph B. Baldwin Prize in
Astrophysics and Space Sciences is an award sponsored by a generous gift to the University by Dr. Ralph B. Baldwin.