Carrie Filion

Local Group Archaeologist

Flatiron Research Fellow

Ph.D. in Astronomy and Astrophysics from Johns Hopkins University

I’m Carrie, a research fellow at the Center for Computational Astrophysics in the Flatiron Institute. In my work, I use both large simulations and observations of nearby stars to help us better understand how galaxies form and evolve. I am particularly interested in the formation of dynamical structures, like galactic bars, and figuring out what we can learn about the Milky Way and her nearest neighbors with spectroscopic surveys. I am also pioneering a new sonification technique to turn galaxy data into sounds. Learn more about my research below!

Research Interests

I am interested in a variety of topics, ranging from survey planning to galactic dynamics. My research work to date includes analyses of the stellar populations of ultra-faint dwarf galaxies, the dynamics of stars in barred galaxies, and preparations for the resolved-star component of the upcoming Subaru Prime Focus Spectrograph survey. Lately, I’ve been thinking about 2D and 3D basis function expansions as a framework for investigating and describing galactic structure evolution. I use 2D basis function expansions to map images of galaxies to sound, and I am interested in sonification as both a novel research tool and as a way to make astronomy more inclusive.

Education

Undergraduate

Bryn Mawr College, Bryn Mawr, PA USA

2015 - 2018, A.B. with Honors in Physics, graduated Magna Cum Laude

Undergraduate thesis work advised by Prof. Kate Daniel

Graduate

Johns Hopkins University, Baltimore, MD, USA

2018 - 2024, Ph.D. in Astronomy and Astrophysics

Dissertation work advised by Prof. Rosemary F.G. Wyse

Publication List

on ADS, ORCiD

• First Author

  • “The Low-Mass Stellar Initial Mass Function in Nearby Ultra-Faint Dwarf Galaxies”, Filion, C., Wyse, R.F.G., Richstein, H., Kallivayalil, N., van der Marel, R.P., Sacchi, E., 2024, ApJ, 967, 165
  • “The Non-Axisymmetric Influence: Radius and Angle-Dependent Trends in a Barred Galaxy”, Filion, C., McClure, R.L., Weinberg, M., D’Onghia, E., Daniel, K.J., 2023, MNRAS, 524, 276
  • “Faint Stars in a Faint Galaxy. II. the Low-Mass Stellar Initial Mass Function of the Boötes I Ultrafaint Dwarf Galaxy”, Filion, C., Platais, I., Wyse, R.F.G, Kozhurina-Platais, V., 2022, ApJ, 939, 38
  • “The Far-away Blues: Exploring the Furthest Extents of the Boötes I Ultra-faint Dwarf Galaxy”, Filion, C., Wyse, R.F.G, 2021, ApJ, 923, 218
  • “Faint Stars in a Faint Galaxy. I. Ultradeep Photometry of the Boötes I Ultrafaint Dwarf Galaxy”, Filion, C., Kozhurina-Platais, V., Avila, R., Platais, I., Wyse, R.F.G, 2020, ApJ, 901, 82

• Nth Author

  • “Disc asymmetry characterisation in JWST-observed galaxies at 1 < z < 4”, Ganapathy, A., Petersen, M.S., Yaaqib, R., Filion, C, 2024 Submitted
  • “[X/Fe] Marks the Spot: Mapping Chemical Azimuthal Variations in the Galactic Disk with APOGEE”, Hackshaw, Z., Hawkins, K., Filion, C., et al., 2024 Accepted, ApJ
  • “Detection of a Spatially Extended Stellar Population in M33: A Shallow Stellar Halo?”, Ogami, I., et al including Filion, C., 2024 ApJ, 971, 1
  • “Radial phase spirals in the Solar neighbourhood”, Hunt, J., et al including Filion, C., 2024, MNRAS, 527, 4
  • “The structure of the stellar halo of the Andromeda galaxy explored with the NB515 for Subaru/HSC. I.: New Insights on the stellar halo up to 120 kpc”, Ogami, I., et al including Filion, C., 2024, submitted to MNRAS
  • “RomAndromeda: The Roman Survey of the Andromeda Halo”, Dey, A., Najita, J., Filion, C., et al., 2023, Roman White Paper on the arXiv
  • “Revealing Mass Distributions of Dwarf Spheroidal Galaxies in the Subaru-PFS Era”, Hayashi, K., Dobos, L., Filion, C., Kirby, E., et al., 2023, Accepted for publication in the Proceedings of the IAUS 379

Additional Info

Collaborations

Beyond Basis Function Expansion (B-BFE) link coming soon

Subaru Prime Focus Spectrograph (PFS) Collaboration

Mad Astro Dynamics Research Group

Awards and Grants

American Physical Society Women in Physics Group Grants, 2023 *

American Astronomical Society International Travel Grant, 2022

NASA FINESST Grant, 2020

Alumni Association Student Grant *

* - successful grant proposal that I led on behalf of a service-oriented group

Observing Proposals

Prime Focus Spectrograph Subaru Strategic Program (PFS SSP), In preparation , CO-I on a proposed a 365-night survey to be conducted on the Subaru PFS.

Cool Subdwarfs in the Galactic Halo, Submitted , CO-I on a program to observe candidate cool subdwarfs in the Milky Way stellar halo using unfilled fibers on the Subaru PFS

Deciphering the Outer Halo of the Galaxy with Blue Horizontal Branch Stars, Submitted , CO-I on a program to observe candidate blue horizontal branch stars using unfilled fibers on the Subaru PFS

The ZERO survey - Search for zero-metal stars in the Galaxy with HSC/NB395, Successful , CO-I on a program requesting 2.5 nights on Subaru’s Hyper Suprime-Cam in 2021/2022