Hubble's Constant, the Oosterhoff Dichotomy and Hydrogen Ionization Fronts
We review the evidence for a non-linear Cepheid PL relation in the LMC and estimate the effect this may have on estimates of Hubble's constant. We describe one possible physical mechanism which could cause such a nonlinearity and extend this physics to study RR Lyraes and the Oosterhoff dichotomy.
Atoms and Molecules at High Redshift
Novel Applications of High-Precision Astronomical Techniques to the Study of Binary Stars
The search for extrasolar planets motivated the developent of high-precision astronomical techniques, mainly radial velocities and photometry. In binary stars the measured phenomena are much easier to detect with conventional moderate precision techniques. However, the new techniques may be sensitive to the next-order weaker effects of Relativity. In the talk I will propose ways to utilize Relativity via high-precision astronomy, in order to gain more knowledge about binary stars. Specifically, precise radial velocities may allow absolute mass measurements of binaries, whereas precise photometry (from space) will allow the detection of a large number of spectroscopic binaries.
Talks are on Mondays at 12:40 pm
Talks are generally in either Astronomy (Bryant 217) or Physics (room 2165).
Created: August 23, 2009
Maintained by Althea Moorhead