4 papers
Element Abundances in Nearby Galaxies
Donald R. Garnett
In these lectures I present a highly opinionated review of the observed patterns of metallicity and element abundance ratios in nearby spiral, irregular, and dwarf elliptical galax…
The O II Recombination Line Abundance Problem in Planetary Nebulae
D. R. Garnett, H. L. Dinerstein
We present new observations of O II recombination lines in ten bright planetary nebulae, along with spatially-resolved measurements of O II and [O III] in the Ring nebula NGC 6720,…
The saturation of disk heating in the solar neighborhood and evidence for a merger 9 Gyrs ago
Alice C. Quillen, Donald R. Garnett
We re-examine the age-velocity dispersion relation in the solar neighborhood using improved stellar age estimates that are based on Hipparcos parallaxes and recent stellar evolutio…
Dating of H II Regions from Ionization Modeling
Donald R. Garnett
The emission-line spectrum of an H II region essentially reflects the shape of the EUV spectral energy distribution of the OB stars that ionize the gas. In principle one can use th…