Research

Ongoing research includes the study of the structure and evolution of close binary stars through modeling of observables such as light and velocity curves, extracting orbital and stellar parameters from observational data, and interpreting the data in terms of the structure and evolution of the component stars; the multifrequency variations of quasars, blazars, and other types of AGNs via both visual and high-energy (UV, X-ray, gamma ray) observations; and the evolution of star formation in dwarf galaxies with a focus on the atomic gas (HI) properties (see the LITTLE THINGS project at http://www.lowell.edu/users/dah/littlethings/).

Facilities used include the two SARA telescopes located at Kitt Peak National Observatory in Arizona and at Cerro Tololo Inter-American Observatory in Chile (http:www.astro.fit.edu/sara/sara.html), as well as the Very Large Radio Telescope operated by the National Radio Astronomy Observatory (http://www.vla.nrao.edu/).