Email
Charlotte.Gehan@astro.up.pt

Biographic Notes
Charlotte Gehan is a researcher at IA of Porto. She was awarded a first degree in Physics in 2013 and a Master degree in Astronomy and Astrophysics in 2015 by the Pierre and Marie Curie University (UPMC) located in Paris, France, as well as a PhD by Paris Observatory, located in Paris, France, in 2018. She is a member of IA since 2019. She previously had a post-doc position in LESIA, Paris Observatory, France, during the period 2018-2019.

She is working on asteroseismology of red giant stars. During her PhD she developed a method allowing large-scale measurements of the mean core rotation of stars on the red giant branch observed by the Kepler space telescope, emphasizing that rotation is constant along the red giant branch with values independent of the stellar mass. Current research interests focus not only on both data analysis of oscillation spectra but also on modelling of stellar evolution. She is in particular working on the large-scale measurement and the analysis of the inclination angle of the rotation axis of stars on the red giant branch observed by Kepler, and on the modelling of the angular momentum extraction from red giant cores using the Modules for Experiments in Stellar Astrophysics (MESA) evolution code. She plans to work on deriving global asteroseismic parameters for red giants observed by the TESS space telescope that are candidates for hosting exoplanets, as well as inclinations for cluster stars.

She has been actively involved in teaching and public outreach at Paris Observatory. She taught during three years at an academic level, supervising tutorials in signal processing as well as night observations with telescopes and processing of the obtained images. She also contributed to school teachers' training in astronomy through hands-on computer sessions, was part of on line academic teachings in electromagnetism and astrophysics, and co-supervised academic trainees.
Regarding public outreach, she was during one year a scientific facilitator at Palais de la Découverte, Paris, France, in the frame of a complementary PhD mission, where she gave interactive presentations about stars and asteroseismology. She also participated to the scientific mediation operations Spacebus Maroc 2016 (Morocco, 2016) and Planètes en Guyane (French Guiana, 2018) that consisted in itinerant and interactive public outreach to initiate people to astronomy. Moreover, she supervised visits of Paris Observatory for pupils from elementary to high school, and gave several public outreach conferences on stellar evolution and asteroseismology.

Additionally, she co-organised two editions of the annual Elbereth conference aiming at gathering PhD students in astrophysics in the Parisian region (~120 students) to discover ongoing PhD thesis subjects while developing their professional network.

Lastest publications at IA (or with IA Researchers)C. Gehan, T. L. Campante, M. S. Cunha, L. F. Pereira, 2023,
FRA–A new fast, robust, and automated pipeline for the detection and measurement of solar-like oscillations in time-series photometry of red-giant stars,
Astronomische Nachrichten, 344, 35
>> AbstractJ. M. J. Ong, C. Gehan, 2023,
Mode Mixing and Rotational Splittings. II. Reconciling Different Approaches to Mode Coupling,
The Astrophysical Journal, 943, 21
>> AbstractC. Jiang, T. Wu, A. D. Feinstein, K. G. Stassun, T. R. Bedding, D. Veras, E. Corsaro, D. L. Buzasi, D. Stello, Y. Li et al. (including: C. Gehan, T. L. Campante, D. Bossini, M. S. Cunha), 2023,
TESS Asteroseismic Analysis of HD 76920: The Giant Star Hosting an Extremely Eccentric Exoplanet,
The Astrophysical Journal, 945, 12
>> AbstractP. Gaulme, T. Borkovits, T. Appourchaux, K. Pavlovski, F. Spada, C. Gehan, J. M. J. Ong, A. Miglio, A. Tkachenko, B. Mosser, 2022,
KIC 7955301: A hierarchical triple system with eclipse timing variations and an oscillating red giant,
Astronomy & Astrophysics, 668, 26
>> AbstractJ. Tayar, Facundo D. Moyano, M. Soares-Furtado, A. Escorza, M. Joyce, S. L. Martell, R. A. Garcia, S. N. Breton, S. Mathis, S. Mathur et al. (including: C. Gehan), 2022,
Spinning up the Surface: Evidence for Planetary Engulfment or Unexpected Angular Momentum Transport?,
The Astrophysical Journal, 940
>> AbstractFacundo D. Moyano, P. Eggenberger, G. Meynet, C. Gehan, B. Mosser, G. Buldgen, S. J. A. J. Salmon, 2022,
Asteroseismology of evolved stars to constrain the internal transport of angular momentum. V. Efficiency of the transport on the red giant branch and in the red clump,
Astronomy & Astrophysics, 663, 10
>> Abstract