Department or Program
Physics and Astronomy
Abstract
Star formation in galaxies is a very inefficient process, with only about 5% of the available gas in the Universe forming into stars. The current scientific consensus points toward stellar and/or active galactic nuclei feedback as primary energy sources that inhibit star formation and drive galactic outflows, depleting the interstellar medium of star-forming material. This is a comprehensive study of the incidence and quality of outflows in star-forming galaxies as a function of their physical properties. We use spectroscopic data from two Sloan Digital Sky Survey (SDSS) projects: Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) and the Extended Baryon Oscillation Spectroscopic Survey (eBOSS). MaNGA provides us with spatially resolved spectroscopy for nearly a thousand galaxies. We classify them in terms of the strength of their outflow signatures and investigate the relationships between physical properties and the incidence of outflows. We find that galaxies with higher star-formation rate (SFR) and higher SFR surface density are significantly more likely to present clear outflow signatures, whereas we find no significant trend in terms of stellar mass. The eBOSS data contains point-source spectroscopy for more than a million galaxies. We cluster galaxies based on SFR and stellar mass and use spectral stacking to increase our signal-to-noise ratio. We then perform spectral fitting and absorption line analysis on the stacked spectra to calculate outflow velocities and investigate correlations with physical parameters. We quantify the positive correlation between outflow velocity and SFR (and specific SFR), and find no significant relationship between outflow velocity and stellar mass.
Level of Access
Open Access
First Advisor
Diamond-Stanic, Aleksandar
Date of Graduation
5-2025
Degree Name
Bachelor of Science
Recommended Citation
Villalta Lopez, Brandon G., "Galactic Winds in MaNGA and eBOSS: A Comprehensive Study of the Relationship Between Galaxies and their Outflows Over the Last Eight Billion Years" (2025). Honors Theses. 484.
https://scarab.bates.edu/honorstheses/484
Number of Pages
57
Components of Thesis
thesis (pdf)
