Stars serve as chemical time capsules that preserve the composition of their birth environment. By studying the compositions of stars with different ages, we can trace the chemical evolution of our Milky Way over time. I am constructing a high precision chemical abundance catalog of a few thousand stars in the Solar neighborhood. What sets this catalog apart from most is that I am determining abundances differentially, which is a technique that enables exceptionally high precisions and accuracies that are impossible using standard techniques. Once completed, this will be the largest differential abundance catalog to date and enable unprecedented high precision constraints of our Solar neighborhood’s chemical history.

→ Manea C., Bedell M., Zasowski G., et. al, 2026, in prep.

Asymptotic giant branch (AGB) stars play an important role in our Milky Way. The end life stage of stars above ~0.8 solar masses, AGB stars produce half of the Galactic reservoir of elements heavier than iron via the slow (s-) neutron-capture process. Understanding their nucleosynthetic output is critical for developing representative, physically-motivated models of Galactic chemical evolution. Much of my research focuses on AGB stars and their output. The most notable result of my research has been bringing attention to the unique behavior of neutron-capture elements in the disk, a historically neglected family of elements.

→ Levine J., Manea C., et al. 2026: “Barium Stars Across the Milky Way: Probing Their Origins via the GALAH Survey”

→ Manea C., et al. 2025: “Optical Spectroscopy Reveals Hidden Neutron-capture Elemental Abundance Differences among APOGEE-identified Chemical Doppelgängers”

→ Manea C., et al. 2024: “Chemical Doppelgangers in GALAH DR3: The Distinguishing Power of Neutron-capture Elements among Milky Way Disk Stars”

→ Manea C., et al. 2022b: “Chemical Abundances of Eight Highly-extincted Milky Way Planetary Nebulae”

Historically, chemically characterizing brown dwarfs and exoplanets has been impossible as we simply did not have the data or tools to do it. Thanks to advancements in instrumentation (e.g., JWST) and chemical characterization techniques (e.g., atmospheric retrievals), we are well-posed to begin studying exoplanet and brown dwarf compositions. However, chemical characterization of these systems is still difficult. For brown dwarfs and exoplanets with associated main sequence star hosts, we can use the chemical composition of the host star to anchor and calibrate the compositions of these lower mass companions. Furthermore, differences between the composition of a host star and its lower mass companion can trace formation pathways. I have been collaborating with brown dwarf and exoplanet experts across the US to chemically characterize the FGK hosts to these lower mass objects.

→ Phillips C., Bedell M., and Manea C. 2026, in prep.
→ Rothermich A., Faherty F. K., Burningham B. Manea C., et al. 2026, submitted.
→ Zhang Z., Molliere P., Hawkins K., Manea C., et. al, 2023 “ELemental abundances of Planets and brown dwarfs Imaged around Stars (ELPIS). I.”

and more upcoming!

Molecular clouds, the sites of star formation, are turbulent in nature. Though the Milky Way is a chemically diverse environment and stars are constantly dying and enriching the interstellar medium, molecular clouds work as blenders that chemically homogenize the star forming environment. Thus, we expect stars that form together to be chemically similar. The degree of similarity (or lack thereof) reveals the mixing physics that powers molecular clouds. My first paper used GALAH survey data to chemically characterize several newfound clusters of stars. Recently, I have been interested in wide binaries both for testing assumptions of chemical homogeneity and for constraining interesting stellar physics that requires the assumption of homogeneity (similar to the previous set of projects).

→ Ongoing project with a newly hired undergraduate student at the University of Utah! “Wide Binaries as Laboratories for Stellar Astrophysics”

→ Manea C., et al. 2022a: “A GALAH view of the chemical homogeneity and ages of stellar strings identified in Gaia”