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Geha Research Group

Welcome to the Geha Research Group at Yale University in the Department of Astronomy. We are focused on understanding low mass galaxies around our Milky Way, in the Local Group and nearby Universe. Low mass galaxies provide significant constraints on galaxy formation processes, cosmology and the nature of dark matter. We study low mass galaxies ranging from gas-rich dwarf galaxies in isolation, to the least luminous and most dark matter-dominated galaxies in orbit around the Milky Way. The Geha group has weekly research meetings and welcomes postdocs, graduate and undergraduate students.

See some of the recent work from the group below.

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Research Interests

Outreach & Teaching

Recent Work

  1. Kado-Fong, Erin, Geha, Marla, Mao, Yao-Yuan, de los Reyes, Mithi A. C., Wechsler, Risa H. et al.; (Includes Asali, Yasmeen); 2024; SAGAbg. II. The Low-mass Star-forming Sequence Evolves Significantly between 0.05 < z < 0.21; Astrophysical Journal; 10.3847/1538-4357/ad8137
  2. Burke, Colin J. and Natarajan, Priyamvada and Baldassare, Vivienne F. and Geha, Marla; 2024; Multi-wavelength constraints on the local black hole occupation fraction; arXiv e-prints; 10.48550/arXiv.2410.11177
  3. Cerny, W., Chiti, A., Geha, M., Mutlu-Pakdil, B., Drlica-Wagner, A. et al.; 2024; Discovery and Spectroscopic Confirmation of Aquarius III: A Low-Mass Milky Way Satellite Galaxy; arXiv e-prints; 10.48550/arXiv.2410.00981
  4. de los Reyes, Mithi A. C., Asali, Yasmeen, Wechsler, Risa, Geha, Marla, Mao, Yao-Yuan et al.; (Includes Kado-Fong, Erin, Gandhi, Pratik J.); 2024; Stellar Mass Calibrations for Local Low-Mass Galaxies; arXiv e-prints; 10.48550/arXiv.2409.03959
  5. Kado-Fong, Erin, Geha, Marla, Mao, Yao-Yuan, de los Reyes, Mithi A. C., Wechsler, Risa H. et al.; (Includes Asali, Yasmeen); 2024; SAGAbg. I. A Near-unity Mass-loading Factor in Low-mass Galaxies via Their Low-redshift Evolution in Stellar Mass, Oxygen Abundance, and Star Formation Rate; Astrophysical Journal; 10.3847/1538-4357/ad3042
  6. Geha, Marla, Mao, Yao-Yuan, Wechsler, Risa H., Asali, Yasmeen, Kado-Fong, Erin et al.; 2024; The SAGA Survey. IV. The Star Formation Properties of 101 Satellite Systems around Milky Way-mass Galaxies; arXiv e-prints; 10.48550/arXiv.2404.14499
  7. Mao, Yao-Yuan, Geha, Marla, Wechsler, Risa H., Asali, Yasmeen, Wang, Yunchong et al.; (Includes Kado-Fong, Erin); 2024; The SAGA Survey. III. A Census of 101 Satellite Systems around Milky Way-mass Galaxies; arXiv e-prints; 10.48550/arXiv.2404.14498
  8. Cerny, W., Drlica-Wagner, A., Li, T. S., Pace, A. B., Olsen, K. A. G. et al.; (Includes Geha, M.); 2023; DELVE 6: An Ancient, Ultra-faint Star Cluster on the Outskirts of the Magellanic Clouds; Astrophysical Journal, Letters; 10.3847/2041-8213/aced84
  9. Cerny, W., Martı́nez-Vázquez, C. E., Drlica-Wagner, A., Pace, A. B., Mutlu-Pakdil, B. et al.; (Includes Geha, M.); 2023; Six More Ultra-faint Milky Way Companions Discovered in the DECam Local Volume Exploration Survey; Astrophysical Journal; 10.3847/1538-4357/acdd78
  10. Guerra, Juan and Geha, Marla and Strigari, Louis E.; 2023; Forecasts on the Dark Matter Density Profiles of Dwarf Spheroidal Galaxies with Current and Future Kinematic Observations; Astrophysical Journal; 10.3847/1538-4357/aca8a5