CAREER: The Cosmic Metallicity and Star Formation History of Galaxies

University Of Hawaii, Honolulu

Investigators

Abstract

Observing the metallicity and star formation history of galaxies since the earliest times in the universe is crucial to understanding galaxy formation and evolution. Theory suggests that metallicity changes less rapidly than star formation rate as a function of redshift, but there is no firm observational foundation for the cosmic metallicity history of star-forming galaxies. To address this, Dr. Lisa Kewley (University of Hawaii) will carry out a program to gain a simultaneous understanding of the metallicity and star formation history of galaxies between 0 < z < 3. This research builds upon the foundation laid by Dr. Kewley for diagnosing and interpreting the metallicity and star-formation properties of galaxies. The observations to be carried out in this program will: (1) impact the use of Gamma-Ray Burst (GRB) hosts as tracers of star formation and metallicity to high redshifts by determining the relationship between GRB hosts and the general galaxy population, (2) uncover the relationship between metallicity and large-scale structure using the unprecedented large area and completeness of new intermediate redshift surveys, and (3) provide a solid observational understanding of the cosmic metallicity and star formation history of galaxies. The observed metallicity history will be compared with predictions from semi-analytic models and cosmological hydrodynamic simulations, providing a critical test of our current theoretical understanding of galaxy formation and evolution. This research will be incorporated into the University of Hawaii Active (inquiry-based) Learning Astronomy 110 class being developed by Dr. Kewley to engender an understanding of Hawaii's past and present role in astronomy. The research program will also be integrated into the University Hawaii Student/Teacher Astronomy Research (HI STAR) program, which targets years 9-12 native Hawaiian or other minority students from low socioeconomic backgrounds. Dr. Kewley will develop for the HI STAR program a spectroscopy lab and galaxy evolution project and, with her research group, will mentor HI STAR students for Science Fair projects using spectra obtained as part of the research program. By promoting a solid understanding of spectroscopy and sharing the excitement of astronomical discovery, this program aims to strengthen the physics and astronomy background of underprivileged students in Hawaii, and motivate them to pursue a career in science.