My Research Projects
Explore the research projects I've worked on by clicking on the panel below.
What is the nature of Little Red Dots?
We explore the nature of high-redshift optically red galaxies between z = 5 and 8 using SED fitting techniques.
Unpublished Projects
- The History of Sag A* — Using outputs from the Illustris-TNG simulation to explore the mass history of the undermassive supermassive black hole at the center of the Milky Way galaxy.
- Search for DCBH Galaxies — Used archival Hubble Space Telescope data to find candidate Direct Collapse Black Hole galaxies at z = 6. Presented at the Banneker Institute Summer Symposium (2020).
- Measuring Stellar Variability — More information coming soon.
Exploring the AGN Fraction of a Sample of JWST's Little Red Dots at 4 < z < 8: Overmassive Black Holes Are Strongly Favored
Background: Little Red Dots (LRDs) are a class of high-redshift (5 < z < 9), optically red, compact galaxies
discovered by the James Webb Space Telescope. Their redshift range makes them particularly valuable to the study of galaxy evolution,
as they are likely progenitors of the massive galaxies we observe in the local universe.
Analyses of LRDs have uncovered a number of peculiar characteristics: high stellar masses relative to their compact size,
potentially overmassive black holes, X-ray faintness, infrared non-detections, and broad Hα emission with weak or absent Hβ.
Our work focuses specifically on the claim that LRDs host overmassive black holes, and asks whether this result holds
regardless of the assumptions made during SED modeling — in particular, how the modeled AGN contribution affects the inferred black hole mass.
Methodology: Using JWST photometry from
Perez-Gonzalez+23,
we modeled the SEDs of LRDs as pure AGN, pure galaxy, or a composite of both, in order to characterize the nature of these sources.
SED modeling decomposes the observed emission into contributions from different physical components — in this case star formation and AGN activity —
allowing us to infer the dominant source of emission and extract physical properties such as black hole mass.
We used the publicly available CIGALE SED modeling code, varying the AGN contribution from 0% to 99%
to systematically probe all three scenarios.
Results: We were the first to demonstrate that the overmassive black hole result in LRDs depends
on the assumed AGN contribution during SED fitting.
For LRDs with an AGN contribution below 20%, the inferred black hole mass is consistent with the local
Reines & Volonteri 2015 scaling relation.
Contributions between 20–40% yield moderately overmassive black holes, while contributions above 40% produce
extremely overmassive black holes consistent with the high-redshift
Pacucci+23 relation.
Additional results can be found in the full paper
here.