I am particularly interested in the Chemically Peculiar A-type stars called the Metallic-lined (Am) Stars. These stars exhibit an apparent underabundance of calcium and scandium, overabundances of iron-group elements, and extreme enhancements of rare-earth elements. The Am stars are slowly rotating stars and nearly all are members of binary systems. The abundance anomalies are thought to be due to radiative diffusion of elements within the stable atmospheres of these stars.
Between 2000 and 2009 I was on the Organizing Committee of the International Astronomical Union Working Group on Ap and Related Stars. The aim of the Working Group is to promote and facilitate research concerning A-type and related stars which exhibit chemical peculiarities and other related phenomena.
For the latest news on the study of Chemically Peculiar Stars, see A Peculiar Newsletter.