Department of Physics and Astronomy


University of Wyoming Physics & Astronomy Colloquium Series

Fridays -- 4:10 PM -- Prowse Room 234

Pre-Colloquium tea served at 3:45 in the Cinnamon Room, PS 237

Tentative Fall 2003 Schedule

September 12 Mary Putman (U. Colorado)
What Goes On In the Dark of Galaxy Halos?

The content of a galaxy's halo defines how the galaxy has formed and evolved. Most halos consist of a mixture of gas, stars, and dark matter, with much of the halo gas being both enriched and ionized. The halo material may have a mixture of origins which include the remnants of mergers and satellite accretion, infalling intergalactic gas, and galaxy outflow material. This talk will discuss the origins of the baryons in galactic halos by examining accreting satellites around our Galaxy and high-latitude bursts of star formation found in other galaxy halos.

September 26 Andrea Schweitzer (Southwest Research Institute)
I have measured absolute proper motions of nearby dwarf spheroidal (dSph) galaxies out to 70 kpc. After combining with radial velocities, I calculated the total space velocities and then dSph orbits. DSph galaxies make handy test particles for measuring the mass of our Galaxy, and the distribution of dark matter. Along with the results of my work, I'll also share some of the stories that went along with my research. I am one of the last people to do a photographic (!) dissertation. So please come and hear about: raiding Allan Sandage's plate vault, - prime focus observations from inside the Palomar 200 -in and Kitt Peak 4-m telescopes, and - the alchemy of yaks, a critical constituent of my work.
October 3 Ed Churchwell (University of Wisconsin)
The SIRTF Mission and the GLIMPSE Legacy Program
A general description of the SIRTF mission and its Legacy Science programs will be briefly described. A more detailed description of the GLIMPSE Legacy program will be given including the program timeline and data products. I will focus significant time on the science that the GLIMPSE data will enable and describe some of the science that the GLIMPSE team is planning to do. The philosophy of the Legacy Science programs is that the Legacy data will become almost immediatedly available to the public, essentially ready for scientific analysis, to benefit from the creative input from the larger community and to enhance the scienfific return from the SIRTF mission. THE LEGACY SCIENCE PROGRAMS WILL ONLY BE A SUCCESS IF THEIR DATA PRODUCTS ARE ACTIVELY USED BY THE SCIENTIFIC COMMUNITY.
October 10 Greg Taylor (NRAO)
Imaging the Afterglows from Gamma-Ray Bursts
Using Very Long Baseline Interferometry (VLBI) the radio afterglows of Gamma-Ray Bursts can be imaged at sub-milliarcsecond resolution. Absolute astrometry to localize the burst within the host galaxy, or to constrain proper motions has also been achieved at similar levels. Several GRBs have been detected with this technique in recent years. The nearby (z=0.1685) gamma-ray burst of 29 March 2003 has presented us with a unique opportunity to study an event with unprecedented clarity. This burst reached flux density levels at centimeter wavelengths more than 50 times brighter than any previously studied event. I will present the results of VLBI observations at multiple epochs designed to measure source diameters and proper motions of GRB 030329 at sub-milliarcsecond levels. These observations can constrain theories describing the dynamical evolution of the fireball.
October 24 Pat Hall (Princeton University)
Quasar Science with the Sloan Digital Sky Survey

The Sloan Digital Sky Survey (SDSS) is revolutionizing the study of quasars and other active galactic nuclei. The survey is obtaining five-band CCD imaging and multifiber spectroscopy over close to one-fourth of the entire sky. Quasars are efficiently identified as objects which have colors different from those of stars and galaxies. The spectra have wavelength coverage, signal-to-noise, and resolution superior to almost all past quasar surveys. I will summarize the wealth of science being done using this huge, high quality dataset, such as: studies of dust reddening in quasars, quasar variability, and discovery of rare populations including obscured (Type II) quasars and unusual broad absorption line quasars

Wed, Oct 29 (special) David Hafemeister (Cal Poly) - The Failure to Link E&M Fields and Cancer
Since the 1979 epidemiology study by Wertheimer and Leeper, there has been a large public and scientific response to the possibility that cancer can be caused the electromagnetic fields. This talk will review some of the (1) epidemiology, (2) biophysics experiments, (3) litigation, mitigation, regulations, and prudent avoidance. Most of the talk will apply Maxwell?s equations to some aspect of the interaction of 60 Hz EM fields to biological matter.
November 14 Dana Backman (Franklin & Marshall)
SIRTF, SOFIA, and Nearby Stars with Circumstellar Planetary Material
The IRAS far-IR all-sky survey discovered main sequence stars with circumstellar planetary material, the so-called "Vega phenomenon". Surveys of IRAS data supplemented by later information from the ISO spacecraft and 2MASS groundbased near-IR survey reveal that approximately 15% of nearby normal field stars have significant amounts of cold solid debris around them, the dust component of extrasolar Kuiper Belts. Statistics of circumstellar debris versus stellar characteristics will be discussed anticipating great advances in our understanding of these objects to be expected from SIRTF and SOFIA observations.
December 5 Jim Baker-Jarvis (National Institute of Standards and Technology)
Recent Advances at the NIST Electromagnetic Properties of Materials Project in Experimental and Theoretical Dielectric and Magnetic Spectroscopy from 1 Hertz to 1 Tera-Hertz: Thin Films, Biomaterials, Metamaterials, Atomic-Force Methods, Single Crystals, and Fabry-Perot Resonators (Abstract)

Previous colloquia series: Fall 2002 Spring 2003
Contact for program information: Daniel Dale (ddale @

Updated on Jul 25, 2003