In the past decade, Galactic Chemical Evolution (GCE) has flourished due to surveys like Gaia, LAMOST, and Galex, which have enabled detailed investigations of stellar abundances. Stellar nucleosynthesis has also made strides in calculating both stable and radioactive isotopes, including the heavy isotopes produced by rapid neutron-capture (r-process). However, the astrophysical sources of r-process synthesis remain unknown, with conflicting findings in the literature. Moreover, the initial mass function (IMF) has been confirmed to vary with metallicity, with significant consequences for the evolution of the abundance of several isotopic species.
To address these issues, we introduce GalCEM, a user-friendly GCE model that tracks isotopic abundances over time in a given galaxy. GalCEM automatically adapts the list of tracked isotopes based on the input yields and includes various enrichment channels such as massive stars, low-to-intermediate mass stars, supernovae, neutron star mergers, collapsars, and magneto-rotational supernovae. We present two sets of results: the evolution of light and intermediate elements, and the evolution of heavy elements. Our results are consistent with Galactic abundances up to the extremely metal-poor regime. We conclude by discussing our assumptions and highlighting open problems in the field of GCE.
BIO
Dr. Eda Gjergo is a postdoctoral researcher at Nanjing University's Astronomy and Space Science department, where she conducts theoretical investigations into the chemical enrichment of galaxies. She developed GalCEM, a user-friendly, detailed, and modular GALactic Chemical Evolution Model, during her postdoctoral work at Nanjing University and Wuhan University.
She previously worked on photometric identification of Type Ia supernovae for the Dark Energy Survey (DES) at Argonne National Laboratory (ANL) and conducted analyses on filter transmission for the Large Synoptic Survey Telescope (LSST). She won the 222nd American Astronomical Society (AAS) Chambliss Astronomy Achievement Student Award for her work within the collaboration. During her Ph.D., she became interested in dust modeling, leading the development of a dust evolution code in zoom-in cosmological simulations of galaxy clusters.
