SEMINÁRIO DO DEPARTAMENTO DE ASTRONOMIA
Reconstructing multi-frequency movies of supermassive black holes with PRIMO
a talk by Lia Cordovil Faraco de Medeiros (Princeton University/University of Wisconsin) - In-Person
Abstract:
The sparse interferometric coverage of the Event Horizon Telescope (EHT) makes reconstruction of black-hole images challenging. The dictionary learning algorithm principal component interferometric modeling (PRIMO) builds a principal component basis from high-fidelity numerical simulations of low-luminosity accretion flows. This basis enables reconstruction of images that are both consistent with the interferometric data and that live in the space spanned by the simulations. So far, the EHT has only published images at 230 GHz, but recent and upcoming campaigns will also include simultaneous observations at 345 GHz. The EHT is also interested in probing the temporal variability of image morphology through a series of intermittent observations spanning several weeks to months (i.e., reconstruct a movie of matter swirling around the black hole). I will review the PRIMO algorithm and its application to EHT M87 data. I will then introduce the new multi-wavelength and multi-epoch version of PRIMO. This new version can simultaneously reconstruct multi-frequency images while accounting for correlations between the frequencies. The algorithm can therefore produce a single mass over distance measurement for multiple frequencies and/or observational epochs.
Short-Bio:
Lia Medeiros is originally from Rio de Janeiro, Brazil, and grew up living in several cities both within and outside Brazil. She obtained her bachelor’s in physics and astrophysics from the University of California, Berkeley in 2013. She received her masters and PhD from the University of California, Santa Barbara. A National Science Foundation’s Graduate Research Fellowship Program allowed her to create opportunities to spend a significant part of her PhD at the Steward Observatory at the University of Arizona, and the Black Hole Initiative at Harvard University. After defending her PhD in 2019, she took a National Science Foundation’s Astronomy and Astrophysics Postdoctoral Fellowship to the Institute for Advanced Study in Princeton, New Jersey. She is currently a NASA Einstein Fellow at Princeton University and will begin a faculty position at the University of Wisconsin, Milwaukee in Jan 2025.
Google Meet: https://meet.google.com/pcw-gmem-jyi
Link da transmissão: https://www.youtube.com/c/AstronomiaIAGUSP/live