Dust is a minor component of the interstellar medium but plays a major role in the evolution of the universe and on our capability to observe it. Dr. Lazzati and his group will combine analytical and numerical techniques to study dust particles of all sizes, from the smallest macromolecules and clusters up to micron-sized crystalline and amorphous solids. In the first part of the project structural and optical properties of small dust grains will be computed with density functional theory techniques. Atomic and molecular clusters with up to 1000 atoms will be studied. In the second part models of dust nucleation will be improved by developing a kinetic theory that includes realistic atomic structures, relaxes the assumption of thermal equilibrium, and includes quantization of energy exchanges. Finally, dust yields from stellar atmospheres and winds, supernovae, and AGN outflows will be computed. This project will paint a clearer picture of cosmic dust formation and has the potential to provide the identification of the carriers of the diffuse interstellar bands and of the 2175 Angstrom feature. The optical properties of dust clusters will be an invaluable ingredient for radiation transfer models in galaxies, star formation, and even for atmospheric studies, since soot and carbonaceous cosmic dust share many similarities.
The results of the research will be disseminated to the public through a collaboration between the PI and the North Carolina Museum of Natural Sciences. Dr. Lazzati and museum staff will develop interactive English and Spanish programs for K-12 students and the general public on the evolution of elements and dust in the universe. The programs will eventually be converted into videos that can be shown in museums and schools around the country. Accompanying instructional materials for educators and teachers will be developed. The bilingual character of the activities will be exploited to foster a broader participation of the Hispanic/Latino community in STEM careers. High-school and undergraduate students from underprivileged backgrounds will also join the PI's group for summer research projects.
