Dissertations, Theses, and Capstone Projects
Date of Degree
6-2026
Document Type
Master's Thesis
Degree Name
Master of Science
Program
Astrophysics
Advisor
Ruth Angus
Advisor
Dax Feliz
Subject Categories
Physical Processes | Stars, Interstellar Medium and the Galaxy | The Sun and the Solar System
Keywords
stellar flares, cme, stars, exoplanets
Abstract
This thesis investigates whether archival TESS photometry and SDSS-V spectroscopy can be combined to identify coronal mass ejections (CMEs) from M dwarfs. Beginning from an initial sample of 625,155 SDSS-V targets, we developed a pipeline for cross-matching TESS photometric flare detections with contemporaneous SDSS-V spectroscopic visits, identifying 20 M dwarfs with overlapping coverage, and 3 visits (from 2 targets) obtained within 1 hour of a detected white-light flare. These two targets, and all corresponding spectra were analyzed in detail using local continuum normalization and Gaussian (single and double) MCMC line profile fitting of Hα and Hβ Balmer lines. For Target 1 (TIC 24056288/ SDSS ID 60965777) we confirm Hα and Hβ flare enhancement relative to quiescent visits, with no significant line asymmetry detected to indicate a potential CME. For Target 2 (TIC 233745344/ SDSS ID 69005520) we confirm Hα and Hβ line enhancement during the flare epoch, with an additional blue shifted Hβ component with a velocity offset of 160 km/s. At the spectral resolution of BOSS (R ∼ 2000, ∆v ≈ 150 km s−1), our sensitivity is limited to the highest-velocity CME signatures, consistent with the low detection rates reported in similar SDSS-based searches (Koller et al., 2021). We have also found this star to be a potential binary candidate so further follow up is needed to fully classify the detected asymmetry. Because of this uncertainty we find no robust detection of a CME. Nonetheless, this work establishes a scalable framework for future joint photometric-spectroscopic searches of stellar activity.
Recommended Citation
Bracamonte, Andrea, "Searching for M Dwarf Coronal Mass Ejections with TESS and SDSS-V" (2026). CUNY Academic Works.
https://academicworks.cuny.edu/gc_etds/6754
Included in
Physical Processes Commons, Stars, Interstellar Medium and the Galaxy Commons, The Sun and the Solar System Commons
