Data Mining the DESI Quasar Spectra Survey

Quasars are the most energetic phenomenon in the universe, the powerful outflows emanating from these objects have key roles in cosmological structure formation: Quenching the growth of the host galaxy via injection of large amounts of energy into the galactic medium. Regulating the growth of the central super-massive black hole. Affecting the medium between galaxies by injecting energy into the gas, thus suppressing further gas accretion onto the galaxy.

As an undergraduate researcher in Dr. Nahum Arav's Quasar Outflow Group, I am tasked with analyzing spectrum data of quasars from DESI (Dark Energy Spectroscopic Instrument) between roughly 1200 Å to 2800 Å in the quasar's rest-frame. In this range, I use a program called QSO-ID to help identify absorption doublets primarily of Carbon IV, Silicon IV, Magnesium II, and Nitrogen V. Once identified, the QSO-ID program generates possible locations of absorption troughs from excited states. If these predictions match absorption features in the spectrum, the physical parameters of the quasar outflow can be determined: Distance of the outflow from the central source and its kinetic luminosity. Thus, advancing our understanding of the roles of quasar outflow in the cosmological structure formation.